Tesis: "Heat demands"

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Farah, Hamad. "Hybrid solar system for heat and electric demands in a simple housing within Sweden and China". Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-40596.

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The access to ideal heating and power techniques has always been highly thought after.This is mainly due to the development in housing architecture and the cold nature of certain regions which has led to an increase in popularity of the heating market and modernised heating technologies. The current DH systems make use of CHP plants for thegeneration of power and electricity. These CHP plants for the most part, are powered through biomass and during winter periods the demand for heating is highly increased.The biggest issue with relying on biomass solely is the constant need to burn wasteproducts which not only results in increasing the demand for consuming in more waste,but also results in producing remains (by-products) that cannot be broken down further and hence might require the utilization of land-space (landfills) for their disposal. Solar modules on the other hand, have gained increased popularity in the recent age. This is mainly due their extremely high flexible ability in converting solar irradiance intoelectrical and thermal energies. This study will try to provide a comprehensive study intothe utilization of a hybrid solar system that combines a standard PV module with a flat-plate collector through estimating the energy demands for a simple housing within Sweden and China. This will be the main aim of the study, however the possibilities of integrating this hybrid solar system alongside current DH systems will mostly be discussed in the first sections to proof the possibility of executing such a system. The theoretical work carried out will only include simulations of having just separate,standalone PV and flat-plate collector modules. However, designing a hybrid solar and DH system will not be the major focus of this study. The results at the end of the report,concluded that the electrical production for the Swedish case were noticeably higher thanthat of the Chinese case in spite of maintaining the same load values through both cases and higher solar irradiation for the Chinese case. Due to PVsyst simulation constraints,the results show that the investment cost of the Swedish PV (electrical component) module was about 3.6 times greater than that of the Chinese which could possibly mean that the Swedish case has a bigger PV module area than the Chinese case in order to meetel ectricity demand monthly. However, when it came to the thermal energy production, it was possible to assume different collectors cases and hence an area of 7m2 was chosen for the Swedish perspective while an area of 4m2 has been considered for the Chinese case. The thermal useful energy values where then compared with heating demands for both of the cases. Finally, the thesis concluded that there was no requirement for having an integrated DH network within the standalone houses, having small electricity and heat demand and hence, it might be more beneficial to have an integrated DH and solar system within more densely populated housing areas.
Efterfrågan på tillgången till idealisk uppvärmning och effektiva tekniker har alltid varithög. Detta beror främst på utvecklingen inom arkitektur och den kalla naturen i vissaregioner som har lett till en ökad popularitet av värmemarknaden och moderniseradevärmeteknologiert. De nuvarande fjärrvärme-systemen använder kraftvärmeverk förproduktion av kraft och elektricitet. Dessa kraftvärmeanläggningar drivs till stor delgenom biomassa och under vinterperioderna ökar efterfrågan på uppvärmning mycket.Det största problemet med att förlita sig på biomassa enbart är det ständiga behovet avatt bränna avfallsprodukter som inte bara resulterar i att öka efterfrågan på konsumtionav fler avfallsprodukter utan också resulterar i att producera rester (biprodukter) sominte kan brytas ned ytterligare och därmed kan kräva användning av markutrymme fördeponering. solar-moduler å andra sidan har ökat popularitet under de senaste åren.Detta beror främst på deras extremt höga flexibla förmåga att konvertera solbestrålningtill elektrisk och termisk energi. Denna studie kommer att försöka tillhandahålla enomfattande studie av användningen av ett hybridsolsystem som kombinerar en standardPV-modul med en flatplate collector för att simulera en solar-modul samt caselera enfristående version genom att uppskatta energikraven för en enkel bostad i Sverige ochKina. Detta kommer att vara huvudmålet med studien, men möjligheterna att integreradetta hybrida solsystem tillsammans med nuvarande DH-system kommer mestadels attdiskuteras i de första avsnitten för att bevisa möjligheten att utföra ett sådant system. Detteoretiska arbetet som utförs kommer endast att innehålla simuleringar av att bara ha enfristående PV- och flatplate collector module, men att utforma ett hybrid sol- och DHsystemkommer inte att vara huvudfokus för denna studie. Resultaten i slutet avrapporten drog överraskande slutsatsen att den elektriska produktionen för den svenskacaselen var märkbart högre än den för den kinesiska caselen trots att de båda caselernabibehöll samma belastningsvärden och högre solbestrålning för den kinesiska caselen.Detta kan förklaras av skillnaden i modulpriser vid simulering genom PVsyst därinvesteringskostnaden för den svenska PV-modulen (elektrisk komponent) var ungefär3,6 gånger större än den för kinesiska, vilket innebär att PVsyst antar ett störremodulområde för svensk modul och därmed mer energiproduktion. Men när det kom tillvärmeenergiproduktionen, var det möjligt att anta olika samlarfall och följaktligen valdesett område på 7m2 för det svenska perspektivet medan ett område på 4m2 har beaktatsför den kinesiska och värmevärden för användbar energi där jämfördes sedan med dekrav som krävs för uppvärmning i båda fallen. Slutligen drog avhandlingen slutsatsen attdet inte fanns något krav på att ha ett integrerat DH-nätverk i de fristående husen ochdärför kan det vara mer fördelaktigt att ha ett integrerat DH och solsystem i tätarebebyggda bostadsområden.

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2

Elakanti, Ranjith Reddy y Rajaneesh Kumar Singh. "Sustainability and Diffusion of SolarThermal Technology : A case study on brewery and mining industries". Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448042.

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Energy is the core component for all industries. Most of the energy demand is met by fossil fuels, which is one of the main reasons for the high level of carbon emissions from industries. To decrease emissions or even become carbon neutral by 2050, many companies have made sustainability goals to implement renewablesin their production processes. Industries consume 74% of the energy in the form of heat, of which 30% of energy is consumed in low-temperature applications. Substituting fossil fuels in low-temperature applications with renewable energy sources such as solar-thermal technology (STT) can significantly reduce emissions. This study explores how can focus on sustainability by companies facilitate the diffusion of STT in low-temperature applications in brewery and mining industries. The study comprises a comprehensive literature review on sustainable development, drivers, and barriers of STT. The theoretical framework of the studyis based on diffusion of innovation by Rogers (2003). Empirical data is collected using semi-structured interviews to gain insights from multi-national companies about their focus on sustainability, transition towards renewable energy sources in meeting heat demand and aspects considered by companies. The study results show that companies focusing on sustainability goals are incorporating new renewable energy technologies such as STT in their processes. Companies are also making heat purchase agreements and are collaborating with neighbouring companies to incorporate STT. This form of integration of new solutions can increase the adoption rate of STT. Further, it is found that brewery companies have a better scope of implementing STT compared to mining companies.

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3

Brundin, Carl. "Alternative energy concepts for Swedish wastewater treatment plants to meet demands of a sustainable society". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-146831.

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This report travels through multiple disciplines to seek innovative and sustainable energy solutions for wastewater treatment plants. The first subject is a report about increased global temperatures and an over-exploitation of natural resources that threatens ecosystems worldwide. The situation is urgent where the current trend is a 2°C increase of global temperatures already in 2040. Furthermore, the energy-land nexus becomes increasingly apparent where the world is going from a dependence on easily accessible fossil resources to renewables limited by land allocation. A direction of the required transition is suggested where all actors of the society must contribute to quickly construct a new carbon-neutral resource and energy system. Wastewater treatment is as required today as it is in the future, but it may move towards a more emphasized role where resource management and energy recovery will be increasingly important. This report is a master’s thesis in energy engineering with an ambition to provide some clues, with a focus on energy, to how wastewater treatment plants can be successfully integrated within the future society. A background check is conducted in the cross section between science, society, politics and wastewater treatment. Above this, a layer of technological insights is applied, from where accessible energy pathways can be identified and evaluated. A not so distant step for wastewater treatment plants would be to absorb surplus renewable electricity and store it in chemical storage mediums, since biogas is already commonly produced and many times also refined to vehicle fuel. Such extra steps could be excellent ways of improving the integration of wastewater treatment plants into the society. New and innovative electric grid-connected energy storage technologies are required when large synchronous electric generators are being replaced by ‘smaller’ wind turbines and solar cells which are intermittent (variable) by nature. A transition of the society requires energy storages, balancing of electric grids, waste-resource utilization, energy efficiency measures etcetera… This interdisciplinary approach aims to identify relevant energy technologies for wastewater treatment plants that could represent decisive steps towards sustainability.

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4

Janírek, Martin Stanislav. "Analýza tepelné ztráty větráním pro různě definovaná množství větracího vzduchu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228313.

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The thesis analyses heat loss caused by ventilation for various volumes of ventilated air. Number of model cases were analyzed (class room, fit center, auditorium in the cinema and an apartment). Every scenario was analyzed with the heat recuperation and without it. Annual energetic balance and influence of heat recuperation was evaluated for every model case thereafter. Simulations of ventilation energy consumption were carried out in the TRNSYS 16 program.

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5

Mavrogianni, A. "Modelling domestic space heating demand and heat wave vulnerability within the London urban heat island". Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1352829/.

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The combined effect of climate change and the urban heat island phenomenon is likely to reduce the space heating needs and cold-related mortality risk of urban populations in mid latitude countries during winter; however, it is also expected to increase overheating and heat-related deaths during summer. Identifying the determinant factors for energy demand and thermal comfort across a city is hence a key requirement for energy efficient retrofit and public health strategies. The aim of this thesis was to assess the relative impact of urban warming, built form and fabric characteristics on domestic energy use and overheating risk across a major city, using London as a case study. Two housing stock models were developed: a heat demand model based on steady-state energy use calculation techniques and a multiple linear regression overheating risk meta-model of an existing dynamic thermal simulation program. Input data was derived from existing Geographic Information System databases, national housing surveys and local urban air temperature models. The heat demand model successfully reproduced the ranking of urban areas based on their actual gas consumption (R² = 0.817) in a case study area containing 8.6% of London's dwelling stock. The heat island was found to decrease the average annual domestic heating load by 14% in these urban areas compared to a rural reference site. It was shown that the overheating meta-model can replicate the output of the thermal simulation program (R² = 0.763). It was indicated that highly exposed dwelling types, such as top floor flats and bungalows, as well as internally insulated buildings are likely to present an indoor overheating problem during periods of hot weather. However, the agreement between modelled overheating levels and monitored data collected in 101 London homes in summer 2009 was relatively weak, thus highlighting the modifying role of occupant controlled ventilation for indoor thermal conditions.

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6

Åberg, Magnus. "District Heating Sensitivity to Heat Demand Reductions and Electricity Market Dynamics". Licentiate thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176407.

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Sweden and the rest of the EU member states have to reduce primary energy use andemissions of CO2, and increase the use of renewable energy sources according to the EUclimate change package “20-20-20”. To do this, the energy systems need to use less fossilfuel and to utilise energy resources more efficiently. Reduction of energy use in buildings isan important part of this transformation. In Sweden, district heating is the most commontechnique to supply heat for space heating and domestic hot water to multi-family residentialbuildings in urban areas. Efficiency improvements in buildings connected to district heatingsystems should not be counterproductive from a systems perspective, e.g. causing lessefficient total use of resources and increased global CO2 emissions. A reduced electricityproduction in combined heat and power plants, which may be a result of reduced districtheating demand, is sometimes seen as problematic with regards to emissions of CO2, sincethis electricity is normally considered to replace electricity produced in less efficient fossilfuelledcondensing power plants.This licentiate thesis summarises the first part of a PhD project that studies thepossibilities for Swedish district heating systems to adapt to a reduced demand for heating inbuildings, as well as to changes in energy markets. In this thesis the impact of buildingenergy-efficiency improvements and electricity market dynamics on the operation of districtheating systems and CO2 emissions is investigated.The energy system cost-optimisation software MODEST has been used to study theimpact of heat demand changes on the heat and electricity production in the Swedish districtheating systems in Linköping and Uppsala. MODEST optimisations were also used toinvestigate the impact of electricity price fluctuations on the operation of the Uppsaladistrict heating system, and the interaction between the national power system and allSwedish district heating systems collectively.The results show that energy efficiency improvements in buildings that reduce heatdemand by up to 40 % do not increase global CO2 emissions due to production of districtheating. This is because heat-only production is reduced to a larger extent than combinedheat and power production. The results also show that low electricity prices during winterand a large introduction of intermittent wind and solar power generation in the Swedishpower system can be expected to induce use of electricity for district heat production and tohamper co-generation of electricity in combined heat and power plants.

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7

Azevedo, Juliana Antunes. "Urban heat and energy demand : application of an urban meteorological network". Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6961/.

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The urban heat island (UHI) effect is an inadvertent modification of climate which leads to increased temperatures in urban areas. This in turn increases localised demand for air conditioning and refrigeration which can be a significant drain on energy resources. At a time of increasing economic, political and environmental concerns with respect to energy policy, security, efficiency and climate change, there is a need to focus efforts to understand energy usage in cities for current and future climates. Using data from an Urban Meteorological Network (UMN) along with a critiqued degree days methodology, this thesis analyses the UHI and estimate current and future cooling demand in Birmingham-UK. From the results it was possible to identify that currently the main factor in energy consumption is income, however when isolating income influence through normalization process it is possible to identify the impact of the UHI. A significant finding was that the distribution of the surface UHI appears to be clearly linked to landuse, whereas for canopy UHI, advective processes appear to play an important role. Analysing Tair data available from the UMN the cooling demand for summer 2013 and future climate scenarios were calculated and demonstrated the importance of high resolution air temperature measurements in estimating electricity demand within urban areas.

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8

Oehme, Sabina. "Demand flexibility potential from heat pumps in multi-family residential buildings". Thesis, Uppsala universitet, Fasta tillståndets fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-355135.

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The Swedish energy power system is in the middle of a paradigm shift where the increased share of intermittent energy sources place higher demand on the ability to regulate and balance the generation and consumption of electricity. Demand flexibility, which means that consumers can adjust their energy consumption, is a promising solution to manage the imbalance in the power system. Electric heat pumps in residential buildings are recognized to have potential to serve as a flexible load. In this thesis, an aggregated multi-family residential building model is developed to generate heat load profiles for a larger number of buildings which facilitate an assessment of the heat pump flexibility. The flexibility assessment is performed for a local distribution grid area with 174 buildings and an electricity price region in Sweden with 10 146 buildings with heat pumps. The flexibility assessment analyses the heat pump load deviation between a base load case and a case where the heat pumps receive an off-signal. The assessment takes into consideration seven flexibility parameters and is conducted for ambient temperatures between -20°C and 15°C. The thermal inertia of multi-family residential buildings facilitates a load shift with a duration of 4.4 to 9.8 hours depending on the ambient temperature. The maximal average power reduction for one hour of 10 MW in a distribution grid and 169 MW in an electricity price region illustrates the potential of using heat pumps as a demand flexibility solution in the electricity grid.

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9

Rajasekeran, Sangeetha. "Enabling Grid Integration of Combined Heat and Power Plants". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/99730.

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In a world where calls for climate action grow louder by the day, the role of renewable energy and energy efficient generation sources has become extremely important. One such energy efficient resource that can increase the penetration of renewable energy into the grid is the Combined Heat and Power technology. Combined Heat and Power (CHP) plants produce useful thermal and electrical power output from a single input fuel source and are widely used in the industrial and commercial sectors for reliable on-site power production. However, several unfavorable policies combined with inconsistent regulations have discouraged investments in this technology and reduced participation of such facilities in grid operations. The potential benefits that could be offered by this technology are numerous - improving grid resiliency during emergencies, deferring transmission system updates and reducing toxic emissions, to name a few. With increased share of renewable energy sources in the generation mix, there is a pressing need for reliable base generation that can meet the grid requirements without contributing negatively to the environment. Since CHP units are good candidates to help achieve this two-fold requirement, it is important to understand the present barriers to their deployment and grid involvement. In this thesis work, we explore some of these challenges and propose suitable grid integration technology as well as market participation approaches for better involvement of distributed CHP units in the industrial and commercial sectors.
Master of Science
Combined Heat and Power is a generation technology which uses a single fuel source to produce two useful outputs - electric power and thermal energy - by capturing and reusing the exhaust steam by-product. These generating units have much higher efficiencies than conventional power plants, lower fuel emissions and have been a popular choice among several industries and commercial buildings with a need for uninterrupted heat and power. With increasing calls for climate action and large scale deployment of renewable based energy generation sources, there is a higher need for reliable base-line generation which can handle the fluctuations and uncertainty of such renewables. This need can be met by CHP units owing to their geographic distribution and their high operating duration. CHPs also provide a myriad of other benefits for the grid operators and environmental benefits, compared to the conventional generators. However, unfavorable and inconsistent regulatory procedures have discouraged these facility owners from actively engaging in providing grid services. Therefore, it is imperative to look into some of the existing policies and understand where the changes and incentives need to be made. In this work, we look into methods that can ease CHP integration from a technological and an economic point of view, with the aim of encouraging grid operators and CHP owners to be more active participants.

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10

Murray, Anthony Gregory. "Three Essays Examining Household Energy Demand and Behavior". Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/28193.

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This dissertation consists of three essays examining household energy decisions and behavior. The first essay examines the adoption of energy efficient Energy Star home appliances by U.S. households. Program effectiveness requires that consumers be aware of the labeling scheme and also change their purchase decisions based on label information. The first essay examines the factors associated with consumer awareness of the Energy Star label of recently purchased major appliances and the factors associated with the choice of Energy Star labeled appliances. The findings suggest that eliminating identified gaps in Energy Star appliance adoption would result in house electricity cost savings of \$164 million per year and associated carbon emission reductions of about 1.1 million metric tons per year. The second essay evaluates household energy security and the effectiveness of the Low-Income Home Energy Assistance Program (LIHEAP), the single largest energy assistance program available to poor households within the United States. Energy security is conceptually akin to the well-known concept of food security. Rasch models and household responses to energy security questions in the 2005 Residential Energy Consumption Survey are used to generate an energy insecurity index that is consistent with those found in the food insecurity literature. Participating in LIHEAP is found to significantly reduce household energy insecurity score in the index. Further, simulations show that the elimination of the energy assistance safety net currently available to households increases the number of energy insecure households by over 16 percent. The third essay develops a five equation demand system to estimate household own-price, cross-price and income elasticities between electricity, natural gas, food at home, food away from home, and non-durable commodity groups. Household cross-price elasticities between energy and food commodities are of particular importance. Energy price shocks reduce food expenditures for low-income households, as indicated by negative cross-price elasticity estimates for food and energy commodities. Additionally, low-income households reduce energy expenditures more than other households, further indicating ``heat or eat'' behavior. Results from all three essays provide policy makers with helpful information to shape future federal energy programs.
Ph. D.

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Lage, Jéssica [UNESP]. "Frequência cardíaca, lactato, custo líquido de transporte e energia metabólica de equinos de marcha batida ou picada da raça Mangalarga Marchador". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143447.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Objetivou-se caracterizar a frequência cardíaca máxima (FCMÁX), a intensidade da prova de marcha oficial e comparar o custo de transporte (COT) e a energia metabólica (P) de equinos da raça Mangalarga Marchador (MM) de marcha picada (MP) ou batida (MB). Ao todo 22 equinos da raça MM participaram deste estudo. O experimento foi realizado em três fases: 1) teste de esforço máximo (TEM), 2) provas oficiais de marcha (POM) e 3) teste padronizado de marcha (TMP). Para caracterizar a FCMÁX, 19 equinos (14 de MB e 5 de MP) realizaram um TEM. Destes, 13 (9 de MB e 4 de MP) foram monitorados durante a POM que foi composta por 4 etapas: marcha, passo, prova funcional e estação. A média da FC de cada etapa da POM foi relacionada à FCMÁX para determinação da sua intensidade relativa. O TPM foi realizado com 14 equinos (9 de MB e 5 de MP), dos quais 11 já haviam participado das etapas anteriores. O COT e P foram calculados a partir dos valores de frequência cardíaca (FC) obtidos durante o TMP. Amostras sanguíneas foram coletadas para análise da concentração plasmática de lactato [Lac]. Aplicou-se o teste t de student e ANOVA de uma via seguida pelo teste Holm-Sidak (P<0,05). A FCMÁX média foi de 211±11 e 214±11 bpm para os grupos MB e MP, respectivamente, não havendo diferença (P>0,05) entre eles. A [Lac] aumentou em decorrência do TEM, sem diferença entre os grupos. Isto indicou que os grupos possuíam a mesma aptidão física. As etapas da POM definidas no nosso estudo diferiram quanto à intensidade relativa à FCMÁX, com exceção da prova funcional e da etapa de marcha, que foram semelhantes entre si (P>0,05). As POM da raça MM podem ser caracterizadas como um esforço de intensidade intermitente e submáxima. Ademais, os equinos de marcha picada se deslocaram com maior exigência energética.
This study aimed to characterize the maximum heart rate (HRMÁX), the intensity of the official marcha test (OMT) and compare the cost of transport (COT) and metabolic power (P) of Mangalarga Marchador (MM) horses of marcha batida (MB) and marcha picada (MP). Twenty-two MM horses participated in this study. The experiment was conducted in three phases: 1) maximal effort test (MET), 2) official marcha test (OMT) and 3) standardized walk test (SWT). To characterize the HRMÁX, 19 horses (14 MB and 5 MP) underwent a MET. Of these, 13 (9 MB and 4 MP) were monitored during the OWT that consisted of 4 stages: walk, marcha, functional test and rest. The average HR in each stage of OMT was correlated to the HRMÁX to determine their relative intensity. The SWT was performed with 14 horses (9 MB and 5 MP), of which 11 had already participated in the previous stages. The COT and P were calculated from the heart rate values (HR) obtained during the SWT. Blood samples were collected to analyze plasma lactate concentration [Lac]. Student t test and one-way ANOVA followed by Holm-Sidak test (P <0.05) were used to analyze the results. The average HRMÁX was 211 ± 11 and 214 ± 11 bpm for the MB and MP groups, respectively, with no difference (P> 0.05) between them. The [Lac] increased as a result of MET, with no difference between groups. This indicated that horses of both groups had the same physical fitness levels. The OMT stages defined in our study differed regarding the relative intensity of HRMÁX, except for the functional test and walk stages, which were similar. The COT and P were higher in the MP group. The OMT of the MM breed can be characterized as an effort of intermittent and submaximal intensity. In addition, the displacement of the marcha batida horses was more energetically efficient.

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Grill, Rebecca. "Market potential for using demand response from heat pumps in multi-family buildings". Thesis, Uppsala universitet, Fasta tillståndets fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354873.

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More renewable energy leads to higher energy imbalances in the Swedish electric power system. In the same time, the grid capacity is almost reached in some regions which requires an extension of the current grids or a reduction of the power consumption. Demand response could be a key factor for both stabilizing the energy balances and reducing the grid congestion. The aim with this thesis is to analyze the potential incomes that demand response from heat pumps can generate for the balance responsibility parties and the grid operators and evaluate how it would affect the end-consumers. The investigated local grid that contains of 174 multi-family buildings with heat pumps could reduce its highest peak power with 2,9 MW. This peak power reduction generated a cost reduction of 483 000 SEK per year or 2800 SEK per building per year in reduced penalty fees and power subscription fees. The mFRR market and the power reserve market were determined to be the most suitable markets for using demand response from heat pumps on for the balance responsibility party in the electricity price region SE3. SE3 consists of 10146 multi-family buildings with heat pumps. The mFRR market generated an average income of 2 699 000 SEK per winter season whereas the power reserve market generated a yearly administrative compensation of 1 133 000 SEK per season and 104 000 SEK per call-off. It is important that end-consumers obtain demand-based tariffs or hourly based tariffs to enable a cost reduction from the control system.

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13

Storry, Rachael Louise. "A multi-objective optimisation approach to the network arrangement of flexible heat demand". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24394.

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The electricity network in the UK is facing a challenging future where environmental and efficiency goals to be met require significant changes in the industry. The rethinking of how distribution networks are arranged and operated is essential due to increasing connections of generation at this level. This also gives significance to the issue of arranging and operating these assets in the most optimal manner. The saturated state of the transmission network has led to the popularity of connecting generation to distribution networks. It becomes evident that, when increasing generation from renewable sources, a means of storing energy is required. One area of storage being investigated for this aim is Electrical Thermal Storage (ETS), which is a form of flexible heating demand. This type of energy storage is cost effective, however it is limited in its application due to the natural dissipation of heat. It is preferable that this heat loss be of use and therefore ETS devices are used in the domestic setting. These devices can be in the form of space storage heaters or hot water storage tanks, which are able to store heat or hot water for up to several days, until the user wishes to make use of the resource. Although decentralised generation and energy storage (Distributed Energy Resources - DER) at first glance appear to be an attractive means for the energy and carbon targets to be met, it can introduce further problems to the electricity network. It is possible for the addition of DER to lead to voltage rise or voltage drop, negatively impact on the protection systems and affect power quality. In order for distribution networks to successfully operate it is important that any new network assets are connected in an optimal manner. This research has modified and used a multi-objective network planning framework to determine the optimal arrangement of ETS devices in distribution networks. The framework is built around the Strength Pareto Evolutionary Algorithm 2 (SPE A2), which takes its inspiration from evolution in nature, and is able to take into consideration the constraints of the network and multiple, conflicting objectives. The framework has been adapted to optimise the number of ETS devices, their location and operation, whilst ensuring that the network will operate within its constraints. The results generated by the planning framework illustrate the potential benefits offered by the inclusion of ETS in distribution networks, as well as demonstrate that the method and tools used are valuable and appropriate.

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14

Soares, Alexandre Kepler. "Calibração de modelos de redes de distribuição de água para abastecimento considerando vazamentos e demandas dirigidas pela pressão". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-13102004-150130/.

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No Brasil, são comuns sistemas de distribuição de água para abastecimento com elevados índices de perdas, nos quais parcela significativa das denominadas perdas físicas é devida às perdas por vazamento. Dessa maneira, o controle efetivo das perdas por vazamento e do comportamento do sistema sob as mais diversas condições operacionais é de fundamental importância, não só do ponto de vista financeiro, no que diz respeito ao desperdício da água bombeada e quimicamente tratada, mas principalmente da preservação deste recurso natural. Com o objetivo de se ter um maior conhecimento do comportamento real de uma rede de distribuição de água, técnicas de calibração, incluindo modelos para avaliação de perdas por vazamentos, vêm sendo propostas. Tais modelos devem considerar a relação pressão x vazamento, bem como a dependência pressão x demanda, face aos diferentes níveis de pressão atuantes em um sistema de distribuição de água. O presente estudo visa o desenvolvimento de uma rotina computacional que considere as perdas por vazamento e a dependência das demandas com a pressão, acoplada ao simulador hidráulico EPANET (ROSSMAN, 2000), utilizando dados de rede hipotética com vistas à calibração em termos das rugosidades absolutas, demandas, diâmetros, cotas topográficas e parâmetros do modelo de vazamentos, bem como a localização de componentes hidráulicos na rede. Para tanto, utilizam-se modelos inversos resolvidos com o suporte da tecnologia dos Algoritmos Genéticos (AGs) e procedimento híbrido (AGs e Método Simplex NELDER & MEAD, 1965)
Brazils water distribution systems usually present a high percentage of so-called physical losses, of which a significant portion is caused by leakage. Therefore, it is of fundamental importance, not only from the financial standpoint in terms of the pumped and chemically treated water but also particularly from that of the preservation of this natural resource, to effectively control leakage and the systems behavior under several operational conditions. In order to gain a better understanding of the real behavior of a water distribution network, several calibration techniques, including models to evaluate leakage, have been proposed. Those models normally consider the correlation between pressure and leakage, as well as the interdependence of pressure and demand in response to the varying levels of pressure in a water distribution system. The present study seeks to extend these models through the development of a computational routine based on leakage and on pressure-dependent demand, in conjunction with the hydraulic simulator EPANET (ROSSMAN, 2000), using the data from a hypothetical network to calibrate the absolute roughness and diameter of pipes, demands and elevations of nodes and the parameters of the leakage model, as well as the location of hydraulic components in the network. To this end, inverse models are used based on the technology of Genetic Algorithms (GA) and the hybrid procedure (GA and Simplex Method - NELDER & MEAD, 1965)

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15

Gummesson, Patrik. "Evaluation of heat pump concepts in ice rinks". Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-141149.

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In Sweden there are about 350 ice rinks in operation today which consume approximately 300 GWh per year. The average energy consumption for a Swedish ice rink is approximately 1000 MWh per year. Ice rink dose not only consume energy it also rejects heat. The rejected heat comes from the refrigeration system that cools down the ice floor. The refrigeration system rejects heat around 700 to 1000 MWh per season. The reason for this study is because of the rejected heat which leads to the question how the rejected heat can be used.The object is to find a heat pump concept that can use the rejected heat or another heat source in an ice rink. Three different heat pump concepts were evaluated. The first heat pump concept use the ice floor as a heat source (called BHP), the second concept use the rejected heat as a heat source (called CHP) and the third concept use the rejected heat to charge an energy storage (called GHP).To accomplish the objective a heat analysis of two ice rinks were made to be able to simulate the heat pump concepts. With the simulation results a life cycle cost was made for a better evaluation. The results from the heat analysis were used for simulating the heat pump concepts. The two ice rinks that were analyzed were Järfälla ice rink and Älta ice rink. The main heat source the two ice rinks uses today is district heating and electricity. Järfälla only use district heating (DH) as a heat source and Älta ice rink use recovery heat, electricity and district heating.The heat analysis of the two the ice rinks showed that the highest district heating consumer was the domestic hot water at 47% of the DH followed by the dehumidifier at 32% of the DH and last the space heating at 22% of the DH. This shows how the heat is used in a general ice rink in Sweden. The temperature levels for the dehumidifier is around 65 °C (only DH part), the domestic hot water at 55 °C and last the space heating at 20 °C. However the heat demand for the ice rinks resulted in 443 MWh for Järfälla and 192 MWh for Älta. To know the size of the heat pump used for the heat pump concepts a heat profile for the ice rinks were made. The result of heat profiles lead to a heat pump size of 105 kW in Järfälla and 45 kW in Älta. The rejected heat for one season in Järfälla is 1000 MWh and 780 MWh in Älta.With the results from the heat analysis the evaluation the heat pump concepts was possible. The COP1 for the CHP resulted at 3,8 and the COP1 for the GHP was assumed to be the same as for the CHP. The COP1 calculations for the BHP concept resulted at 2,5. COP was calculated with collected data from the respective ice rinks refrigeration system. The simulations results were that the BHP and the CHP concept could fulfill the heat demand up to around 79% and the GHP up to around 84% in both ice rinks. The rest of the heat demand is heated with supplementary heat. The life cycle cost (LCC) showed that the CHP concept had the lowest cost followed by the GHP concept. The BHP concept had the highest LCC, because of the low COP. The LCC model dos not include the running cost, the maintenance cost and the energy tariffs for the district heating.The recommended solution is the GHP concept. This is because it is a good investment for the future since other buildings can be connected to the energy storage. The GHP concept is also the solution that fulfills the heat demand best and has the lowest annual energy cost.

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16

Dejvises, Jackravut. "Modelling of flexible heat demand and assessing its value in low carbon electricity systems". Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/10144.

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This thesis presents a thermo-electrical modelling approach for demand response services through Heating Ventilation and Air Conditioning (HVAC) systems. The starting point of the approach is to gain insights on the heating and cooling energy required to keep a building at predefined temperature settings. These studies are supported by the simulation engine EnergyPlus, which is used to generate base-case (uncontrolled) consumption scenarios. Then, a number of different control actions are simulated to study how the energy demand and the indoor temperature profile of different buildings react to such control actions. The relations between user’s comfort levels and temperature setting point variations and durations of the control are explored for different types of buildings. In order to map thermal loads to electrical loads, synthetic and general models of reversible HVAC devices are developed through a so-called black-box approach, whereby input-output functions are generated to link the equipment performance to indoor and outdoor temperatures in both heating and cooling operation. A mathematical formulation of these performance functions is developed from real data. A flexible demand strategy algorithm that maximises the benefits of flexible heat demand is finally presented. It allows selection of an optimal combination of control strategies for the different devices involved in the analysis. The algorithm is able to select type, number, and duration of operation of the HVAC systems so as to maximise the sought benefits, e.g., support of system balancing task, network constraint management. This can ultimately lead to facilitate efficient integration of intermittent generation and enhance the utilization of existing network assets in future low carbon electricity systems. The present heating and domestic hot water demands of UK residential buildings have been modelled and validated with the national gas consumption. The model is used to predict future HVAC demand of the UK residential building in year 2050.

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17

Yates, Bernice Helen. "Illness demands and social support during recovery from a cardiac illness event /". Thesis, Connect to this title online; UW restricted, 1989. http://hdl.handle.net/1773/7268.

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18

Sharp, R. E. "Spatiotemporal disaggregation of GB scenarios depicting increased wind capacity and electrified heat demand in dwellings". Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1476773/.

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National Grid’s future energy scenarios depict increased wind capacity and use of domestic heat pumps under four different pathways at a national annual resolution. The factors which will drive the resultant electricity generation and demand vary over significantly smaller resolutions in both space and time. This study presents a method which disaggregates these scenarios temporally to an hourly resolution and spatially to a 0.5o x 0.5o grid, which covers the GB land mass and offshore waters. The gridded framework facilitates the development of a wind generation simulation model, SpWind, and a hybrid energy demand simulation model, SpDEAM, that are both driven by climate reanalysis data, which provides spatiotemporally homogeneous and accurate hindcasted weather data over the 25 year period of the scenarios. A range of methods are identified and applied to disaggregate non spatial data and redistribute non gridded spatial data to the grid, which depict scenarios, and drivers of wind generation and energy demand. Evaluations of the reanalysis wind speed data, SpWind and SpDEAM demonstrate a reasonable degree of accuracy; the data, in combination with a gridded approach, is appropriate for simulating turbine output and electricity demand, though some uncertainty and error remains. Wind capacity and heat pumps are assigned to the grid, ensuring that each are exposed to realistic weather conditions. The implications of the scenarios on residual demand variability, geographical diversity and extreme events are explored in detail revealing the relative impact of different factors driving demand and supply.

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19

Jalil, Vega Francisca Alejandra. "Development of a systems approach for studying decarbonisation pathways of heat demand in the UK". Thesis, Imperial College London, 2018. http://hdl.handle.net/10044/1/61337.

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In the UK, 45% of the total energy demand in 2016 was used for heating purposes, 68% of which was supplied by natural gas. Credible alternatives for decarbonising heat include district heating combined with low carbon heat sources, heat electrification using heat pumps (with a decarbonised electricity system), or hydrogen-fuelled heat technologies. Adoption of these technologies must proceed alongside network infrastructure investment and developments in the broader energy system, such as increased renewable power generation. At the time of writing, no systematic framework exists that trades off individual building and district heat supply technologies and their associated infrastructures at high spatial resolutions. This work formulates and applies such framework. It presents a mixed integer linear optimisation model that decides on investments and operation of gas, electricity, heat, and hydrogen technologies and associated network infrastructures, for supplying commercial and domestic heat and electricity demands in spatially-resolved urban areas, minimising the net present cost through 2050. This model is implemented to study four key issues related to heat decarbonisation: Comparing different temperature heat networks for decarbonising heat; the effect of spatial resolution in outcomes of energy systems models for heat; the role of hydrogen in heat decarbonisation pathways in the UK; and the sensitivity of heat decarbonisation outcomes to uncertainty in techno-economic parameters. Results show that adoption of heat technologies depends, among several factors, on linear heat density, zone-to-zone connectivity, and scenario-specific techno-economic assumptions such as technology, fuels, or electricity prices. Linear heat density adoption thresholds were found for individual technologies. Medium and high temperature heat networks were adopted in high and medium/high linear heat density zones, respectively. Hydrogen boilers were adopted when enabling gas networks to be retrofitted to transport hydrogen. Finally, spatial resolution was shown to be a determining factor for finding cost-effective heat decarbonisation pathways through energy systems models.

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20

Gentles, Jeremy A., Christine L. Coniglio, Michael T. Mahnken, Joshua M. Morgan, Matthew M. Besemer y Christopher J. MacDonald. "The Demands of a Single Elimination Collegiate Tennis Tournament". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/3971.

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Despite the considerable body of literature describing the demands of tennis, little is known about the accumulated physiological and mechanical loads associated with collegiate tennis tournament play. While microsensors have been used extensively to quantify demands in a variety of sports, particularly accelerometry and GPS sensors, limited data exists describing the demands of tennis match play using such microsensors (1,2). Aim. The purpose of this study was to use heart rate sensors and triaxial accelerometers to investigate the physiological and mechanical loads associated singles and doubles' tennis play during a single elimination collegiate tennis tournament.

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21

Abedin, Joynal. "Thermal energy storage in residential buildings : a study of the benefits and impacts". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25520.

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Residential space and water heating accounts for around 13% of the greenhouse gas emissions of the UK. Reducing this is essential for meeting the national emission reduction target of 80% by 2050 from the 1990 baseline. One of the strategies adopted for achieving this is focused around large scale shift towards electrical heating. This could lead to unsustainable disparity between the daily peak and off-peak electricity loads, large seasonal variation in electricity demands, and challenges of matching the short and long term supply with the demands. These challenges could impact the security and resilience of UK electricity supply, and needs to be addressed. Rechargeable Thermal Energy Storage (TES) in residential buildings can help overcome these challenges by enabling Heat Demand Shifts (HDS) to off-peak times, reducing the magnitude of the peak loads, and the difference between the peak and off-peak loads. To be effective a wide scale uptake of TES would be needed. For this to happen, the benefits and impacts of TES both for the demand side and the supply side have to be explored, which could vary considerably given the diverse physical, thermal, operational and occupancy characteristics of the UK housing stock. A greater understanding of the potential consequence of TES in buildings is necessary. Such knowledge could enable appropriate policy development to help drive the uptake of TES or to encourage development of alternative solutions. Through dynamic building simulation in TRNSYS, this work generated predictions of the space and water heating energy and power demands, and indoor temperature characteristics of the UK housing stock. Twelve building archetypes were created consisting of: Detached, semi-detached, mid-terrace and flat built forms with thermal insulation corresponding to the 1990 building regulation, and occupied floor areas of 70m2, 90m2 and 150m2. Typical occupancy and operational conditions were used to create twelve Base Case scenarios, and simulations performed for 60 winter days from 2nd January. HDS of 2, 3 and 4 hours from the grid peak time of 17:00 were simulated with sensible TES system sizes of 0.25m3, 0.5m3 and 0.75m3, and water storage temperatures of 75°C and 95°C. Parametric analysis were performed to determine the impacts and benefits of: thermal insulation equivalent to 1980, 1990 (Base Case), 2002 and 2010 building regulation; locations of Gatwick (Base Case) and Aberdeen; heating durations of 6, 9 (Base Case), 12 and 16 hours per day; thermostat settings of 19°C, 21°C (Base Case) and 23°C, and number of occupiers of 1 person and 3 persons (Base Case) per household. Good correlation was observed between the simulated results and published heat energy consumption data for buildings with similar thermal, physical, occupancy and operational conditions. The results allowed occupied space temperatures and overall daily and grid peak time energy consumption to be predicted for the range of building archetypes and parameter values considered, and the TES size necessary for a desired HDS to be determined. The main conclusions drawn include: The overall daily energy consumption predictions varied from 36.8kWh to 159.7kWh. During the critical grid peak time (17:00 to 21:00) the heat consumption varied from 4.2kWh to 58.7kWh, indicating the range of energy demands which could be shifted to off-peak times. On average, semi-detached, mid-terrace, and flat built forms consumed 7.0%, 13.8% and 22.7% less energy for space heating than the detached built form respectively. Thermal insulation changing from the 1990 building regulation level to the 1980 and 2010 building regulation levels could change the mean energy use by +14.7% and -19.6% respectively. A 0.25m3 TES size with 75°C water storage temperature could enable a 2 hour HDS, shifting 4.3kWh to 11.7kWh (mean 8.7kWh) to off peak times, in all 70m2 Base Case archetypes with the 60 day mean thermal comfort of 100%, but with the minimum space temperature occasionally dropping below an 18°C thermal comfort limit. A 0.5m3 TES size and water storage of 95°C could allow a 3 hour HDS, shifting 9.8kWh to 28.2kWh (mean 18.7kWh) to off peak times, in all 90m2 Base Case archetypes without thermal comfort degradation below 18°C. A 0.75m3 TES with a 95°C water temperature could provide 4 hour HDS, shifting 13.9kWh to 47.7kWh (mean 27.2kWh) to off peak times, in all 150m2 Base Case archetypes with 100% mean thermal comfort but with the 60 day minimum temperature occasionally dropping below the 18°C thermal comfort limit in the detached built form. Improving the thermal insulation of the buildings was found to be the best way to improve the effectiveness of HDS with TES, in terms of the demand shift period achievable with minimal thermal comfort impact. A 4 hour HDS with 100% thermal comfort is possible in all 90m2 floor area buildings with a 0.25m3 tank and a water storage temperature of 75°C provided that the thermal insulation is as per 2010 building regulation. Recommendations for further research include: 1) creating larger number of archetype models to reflect the housing stock; 2) using heat pumps as the heat source so that the mean effect on the grid from electric heating loads can be predicted; 3) taking into account the costs associated with taking up HDS with TES, in terms of capital expenses and space requirement for housing the TES system; 4) considering alternative methods of heat storage such as latent heat storage to enhance the storage capacity per unit volume; and 5) incorporating zonal temperature control, for example, only heating rooms that are occupied during the demand shift period, which could ensure better thermal comfort in the occupied space and extend the demand shift period.

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22

Martin, Fagernäs. "The Energy Savings Potential of a Heat Recovery Unit and Demand Controlled Ventilation in an Office Building". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184287.

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The building sector is responsible for approximately 40 % of the total energy usage in Sweden. In office buildings the heating, ventilation and air conditioning system can account for up to 55 % of the energy usage. In order to reduce the energy usage of the heating, ventilation and air conditioning system different control methods are often used. One of these control methods is demand controlled ventilation, where the ventilation system is controlled with regard to occupancy with the help of motion and/or CO2 sensors. The aim of this thesis was to determine the energy savings potential of a heat recovery unit as well as demand controlled ventilation in an office building. The effect of longer intervals between sensor control signals to the ventilation system was also investigated. This is done by creating schedules, gathered from actual building occupancy, that are being used to control the occupancy and ventilation in a building model in the building performance simulation software IDA ICE. As a reference building, the fifth floor of the LU1 section of the natural science building at Umeå University is used. The reference building consists of 40 offices for which the occupancies are known. The average occupancy for all the offices combined throughout the investigated time period is determined to be 34.8 %. The results from the simulations indicate that an energy savings potential of 52.98 % can be achieved by a heat recovery unit with an efficiency of 80 % or 95 %, when compared to not having a heat recovery unit. When implementing demand controlled ventilation an energy savings potential of 2.8-11.0 % can be achieved, with the energy savings potential decreasing when the efficiency of the heat recovery unit increases. Finally, it is shown that longer intervals between sensor control signals to the ventilation system leads to a small increase in energy usage and poorer indoor air quality.

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23

Fagernäs, Martin. "The Energy Savings Potential of a Heat Recovery Unit and Demand Controlled Ventilation in an Office Building". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184287.

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The building sector is responsible for approximately 40 % of the total energy usage in Sweden. In office buildings the heating, ventilation and air conditioning system can account for up to 55 % of the energy usage. In order to reduce the energy usage of the heating, ventilation and air conditioning system different control methods are often used. One of these control methods is demand controlled ventilation, where the ventilation system is controlled with regard to occupancy with the help of motion and/or CO2 sensors. The aim of this thesis was to determine the energy savings potential of a heat recovery unit as well as demand controlled ventilation in an office building. The effect of longer intervals between sensor control signals to the ventilation system was also investigated. This is done by creating schedules, gathered from actual building occupancy, that are being used to control the occupancy and ventilation in a building model in the building performance simulation software IDA ICE. As a reference building, the fifth floor of the LU1 section of the natural science building at Umeå University is used. The reference building consists of 40 offices for which the occupancies are known. The average occupancy for all the offices combined throughout the investigated time period is determined to be 34.8 %. The results from the simulations indicate that an energy savings potential of 52.98 % can be achieved by a heat recovery unit with an efficiency of 80 % or 95 %, when compared to not having a heat recovery unit. When implementing demand controlled ventilation an energy savings potential of 2.8-11.0 % can be achieved, with the energy savings potential decreasing when the efficiency of the heat recovery unit increases. Finally, it is shown that longer intervals between sensor control signals to the ventilation system leads to a small increase in energy usage and poorer indoor air quality.

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24

Prandin, Mosè. "Exergy Analysis at the Community Level: matching supply and demand of heat and electricity in residential buildings". Thesis, KTH, Byggnadsteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-35059.

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Most of the energy required by residential buildings is for low temperature heat. Often this demand is met by the use of high quality energy sources such as fossil fuels and electricity. The energy analysis alone does not take into account the quality of energy and so it hides the real potential for the so-called energy savings. Thus the concept of exergy must be involved. In particular the low-exergy approach shows that the energy with low exergy level has to be supplied with energy with similar exergy content. Consequently, the problem is shifted to find energy sources suitable for this purpose. The electricity can be exploited with low exergy losses with high-COP heat pumps. Instead the use of fossil fuels for thermal purposes should be avoided. One of the possibilities is the energy cascade. In this solution the energy flow is used several times, despite its quality decreases with each step, before being discharged into the environment. Thus the use of the district heating from cogeneration for the space heating seems to be an interesting choice. The issues connected to the cogeneration exploitation force to shift the boundary layers of the analysis from the building to the community level. In this work different solutions to meet the electricity and heat demands of a community of houses have been compared. The aim is to show that the results obtained from the low-ex approach allow an effective reduction of fuel consumption through a more rational use of the resources. The comparison was addressed initially in steady-state case and then with the use of the software HOMER also for the dynamic case. To achieve reliable results, this required that the annual profiles for thermal and electrical demand of the reference community are modelled to represent the actual loads as closely as possible. Finally, for each case taken into account, the total consumption, the energy and the exergy efficiencies have been calculated.

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25

Connally, G. H. "The influence of psychological and physical demands on the relationship between heart rate and oxygen consumption". Thesis, University of Hull, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375635.

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26

Hammarström, Anton. "Utvärdering av potential för värmeåtervinning från laborationsutrustning : Möjligheten att använda en kylvattenbassäng som termiskt säsongslager". Thesis, Mittuniversitetet, Avdelningen för kemiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-34309.

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HETA utbildningar i Härnösand har ett ångkraftverk för undervisningssyfte som kyls ner med vatten från en underjordisk bassäng på cirka 329 m³. Syftet med detta examensarbete har varit att undersöka hur bassängen med spillvärmen från kraftverket kan användas som ett säsongslager i kombination med en befintlig 7,8 kW värmepump för att värma upp maskinhallen i deras laboratoriebyggnad. Ett kalkylark skapades i Microsoft Excel för att kunna genomföra beräkningarna. Då mätdata saknades skapades ett simulerat scenario baserat på temperaturstatistik och körschema för kraftverket från år 2017. Transmissionsförluster beräknades för bassängen och maskinhallen. För bassängen användes mestadels observationsdata och kännedom hos personalen, medan maskinhallens isolering i huvudsak fick uppskattas efter byggår. Resultatet blev att värmepumpen med aktuellt körschema kunde täcka cirka 45 % av maskinhallens årliga uppvärmningsbehov. Av de 276 GJ som tillfördes genom kylning av ångkraftverket under ett år beräknades endast 2,7 % kunna utnyttjas till uppvärmning av maskinhallen, på grund av för lite isolering i bassängen. De största begränsningarna för högre täckning och större nyttjande av spillvärmen bedömdes vara placeringen i tid av kraftverkets körningar, och värmepumpens effekt. Om körningarna skulle förläggas i huvudsak till november–april och värmepumpen ersättas med en på 10 kW, skulle 74 % av värmebehovet kunna täckas och över 18 % av spillvärmen utnyttjas. Andra saker som förbättrad isolering i bassängen och större vattenvolym bedömdes också kunna förbättra bassängens kapacitet som energilager.
HETA Education in Härnösand has a steam power plant for educational purposes which is cooled with water from a 329 m³ underground basin. The purpose of this thesis has been to examine how the basin with the waste heat can be used as seasonal thermal energy storage with an existing 7.8 kW heat pump in order to heat the machine room of their lab building. A spreadsheet was created in Microsoft Excel in order to carry out the calculations. As no measurement data was available, a simulated scenario was created based on temperature statistics and the operating schedule for the power plant from the year 2017. Transmission losses were calculated for the basin and the machine room. For the basin, mostly observational data and knowledge among the staff were used, while the insulation for the machine room mainly had to be estimated based on the construction year. The result was that the heat pump, with the current operating schedule, could cover around 45% of the yearly heating demand of the machine room. Of the 276 GJ that were added through cooling of the power plant during a year, according to calculations, only 2,7% could be used for heating the machine hall, due to lacking insulation in the basin. The greatest limitations for achieving a higher heating coverage and a greater usage of the waste heat were assessed to be the placement in time of the power plant runs, and the effect of the heat pump. If the runs would be placed mainly in November–April, and the heat pump replaced with a 10 kW one, around 74% of the heating demand could be covered and 18 % of the waste heat used. Other things, such as increased insulation in the basin and larger water volume were also assessed to be able to increase the capacity of the basin as heat storage.

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27

Olsson, Martin. "Thermal Shape Factor : The impact of the building shape and thermal properties on the heating energy demand in Swedish climates". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-125076.

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In the year 2006, the energy performance directive 2002/91/EG was passed by the European Union, according to this directive the Swedish building code was supplemented by a key measure of energy use intensity (EUI). The implemented EUI equals some energy use within a building divided by its floor area and must be calculated in new housing estate and shown when renting or selling housing property. In order to improve the EUI, energy efficiency refurbishments could be implemented. Building energy simulation tools enables a virtual view a building model and can estimate the energy use before implementing any refurbishments. They are a powerful resource when determine the impact of the refurbishment measure. In order to obtain a correct model which corresponds to the actual energy use, some adjustments of the model are often needed. This process refers to as calibration. The used EUI has been criticized and thus, the first objective in this work was to suggest an alternative key measure of a buildings performance. The results showed that the currently used EUI is disfavoring some districts in Sweden. New housing estate in the far north must take more refined actions in order to fulfill the regulation demand, given that the users are behaving identical regardless where the house is located. Further, the suggested measure is less sensitive to the users’ behavior than the presently used EUI. It also has a significance meaning in building design as it relating the building shape and thermal properties and stating that extreme building shapes must undergo a stricter thermal construction rather than buildings that are more compact. Thus, the suggested key measure also creates a communication link between architects and the consultant constructors. The second objective of this thesis has been to investigate a concept of calibration using the data normally provided by energy bills, i.e. some monthly aggregated data. A case study serves to answer this objective, by using the building energy simulation tool IDA ICE 4.7 and a building located in Umeå, Sweden. The findings showed that the used calibration approach yielded a model considered as calibrated in eleven of twelve months. Furthermore, the method gives a closer agreement to the actual heat demand rather than using templates and standardized values. The major explanation of the deviation was influence of the users, but also that the case study building burden with large heat losses by domestic hot water circulation and thus, more buildings should be subjected to this calibration approach.

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28

Lobban, Stacey y Hana Klimsova. "Demand Forecasting : A study at Alfa Laval in Lund". Thesis, Växjö University, School of Management and Economics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2127.

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Accurate forecasting is a real problem at many companies and that includes Alfa Laval in Lund. Alfa Laval experiences problems forecasting for future raw material demand. Management is aware that the forecasting methods used today can be improved or replaced by others. A change could lead to better forecasting accuracy and lower errors which means less inventory, shorter cycle times and better customer service at lower costs.

The purpose of this study is to analyze Alfa Laval’s current forecasting models for demand of raw material used for pressed plates, and then determine if other models are better suited for taking into consideration trends and seasonal variation.

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29

Daianova, Lilia. "Lignocellulosic Ethanol Production Potential and Regional Transportation Fuel Demand". Licentiate thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-13176.

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Road traffic dominates in domestic Swedish transportation and is highly dependent on fossil fuels, petrol and diesel. Currently, the use of renewable fuels in transportation accounts for less than 6% of the total energy use in transport. The demand for bioethanol to fuel transportation is growing and cannot be met through current domestic production alone. Lignocellulosic ethanol derived from agricultural crop residues may be a feasible alternative source of ethanol for securing a consistent regional fuel supply in Swedish climatic conditions. This licentiate thesis focuses on regional transport fuel supply by considering local small-scale ethanol production from straw. It presents the results of investigations of regional transport fuel supply with respect to minimising regional CO2 emissions, cost estimates for transport fuel supply, and the availability of lignocellulosic resources for small-scale ethanol production. Regional transport fuel demand between the present and 2020 is also estimated. The results presented here show that significant bioethanol can be produced from the straw and Salix available in the studied regions and that this is sufficient to meet the regions’ current ethanol fuel demand. A cost optimisation model for regional transport fuel supply is developed and applied for two cases in one study region, one when the ethanol production plant is integrated with an existing CHP plant (polygeneration), and one with a standalone ethanol production plant. The results of the optimisation model show that in both cases the changes in ethanol production costs have the biggest influence on the cost of supplying the regional passenger car fleet with transport fuel, followed by the petrol price and straw production costs. By integrating the ethanol production process with a CHP plant, the costs of supplying regional passenger car fleet with transport fuel can be reduced by up to a third. Moreover, replacing petrol fuel with ethanol can cut regional CO2 emissions from transportation by half.

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30

O'Brien, Brett Anthony. "Intracellular sodium and the matching of ATP supply to demand in the heart". Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/intracellular-sodium-and-the-matching-of-atp-supply-to-demand-in-the-heart(55e6fbad-6f6c-4315-8a7c-7c50ed71240d).html.

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There is convincing evidence that myocardial intracellular Na+ overload ([Na]i) and metabolic derangement are two important and interconnected pathophysiological features of heart failure. Whether [Na]i elevation plays a causative role in ATP supply-demand mismatching in the heart is unknown. A number of mitochondrial enzymes are stimulated by mitochondrial calcium (Cam) during contraction thereby sustaining production of reducing equivalents to maintain ATP supply. It is postulated that this stimulation is perturbed when [Na]i is high due to increased Cam efflux and that this may be linked with derangement in ATP supply-demand matching. This thesis tests the hypothesis that [Na]i elevation alters intermediary metabolism and energetics in the isolated perfused heart from healthy rats. [Na]i elevation was induced by perfusion with the Na+/K+ ATPase (NKA) inhibitor, ouabain, and measured in real-time using triple quantum filtered (TQF) 23Na nuclear magnetic resonance (NMR) spectroscopy. Blebbistatin was used to transiently uncouple inotropy to better elucidate [Na]i-dependent from inotropy-dependent effects on metabolism and energetics. Real-time 31P NMR measurements showed a transient increase or decrease in both PCr and Pi that mirrored a transient increase or decrease in inotropy. However PCr levels returned to baseline at the end of the protocol while there was a strong negative correlation between [Na]i and [ATP] independent of inotropy. End-point metabolomics were assessed using high resolution 1H NMR and liquid chromatography tandem mass spectrometry (LC-MS/MS). Malate (and more tentatively fumarate) were elevated, suggesting a possible link between [Na]m and TCA cycle activity in the perfused heart. Increased 13C incorporation from [U]-13C-glucose inferred higher TCA cycle activity in hearts with [Na]i overload in the absence of elevated inotropy. This thesis supports that [Na]i elevation can cause ATP supply-demand mismatching in the heart and that increased TCA cycle activity is a possible (mal)adaptive response.

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31

McDaniel, Matthew Lee. "Proposed Design for a Coupled Ground-Source Heat Pump/Energy Recovery Ventilator System to Reduce Building Energy Demand". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/33610.

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The work presented in this thesis focuses on reducing the energy demand of a residential building by using a coupled ground-source heat pump/energy recovery ventilation (GSHP-ERV) system to present a novel approach to space condition and domestic hot water supply for a residence. The proposed system is capable of providing hot water on-demand with a high coefficient of performance (COP), thus eliminating the need for a hot water storage tank and circulation system while requiring little power consumption. The necessary size of the proposed system and the maximum and normal heating and cooling loads for the home were calculated based on the assumptions of an energy efficient home, the assumed construction specifications, and the climate characteristics of the Blacksburg, Virginia region. The results from the load analysis were used to predict energy consumption and costs associated with annual operations.The results for the predicted heating annual energy consumption and costs for the GSHP-ERV system were compared to an air-source heat pump and a natural gas furnace. On average, it was determined that the proposed system was capable of reducing annual energy consumption by 56-78% over air-source heat pumps and 85-88% over a natural gas furnace. The proposed GSHP-ERV system reduced costs by 45-61% over air-source heat pump systems and 52-58% over natural gas furnaces. The annual energy consumption and costs associated with cooling were not calculated as cooling accounts for a negligible portion (6%) of the total annual energy demand for a home in Blacksburg.
Master of Science

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32

Armstrong, Peter Michael. "Enhancing the energy storage capability of electric domestic hot water tanks". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:af140a2c-aab4-4fc9-8709-6f9474079cd5.

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Electric hot water tanks play a pivotal role as demand response assets within the UK's energy system by storing heat when energy is inexpensive and delivering domestic hot water when it is required. This role will become increasingly important if non-dispatchable renewable energy sources are to play a bigger part in the energy mix. Historically, the design standards relating to hot water tanks have focused primarily on minimising heat losses. However, in addition to preserving energy, a hot water tank should preserve the availability of heat above a useful temperature for as long as possible to avoid energy usage during peak times when it is costly or carbon intensive. To do this, thermal stratification within hot water tanks must be promoted. Unfortunately, thermal stratification leads to conditions that are conducive to bacterial growth due to the hospitable temperatures that arise during operation. For this reason, question marks have arisen over the extent to which more flexible control strategies, designed to allow for increasing penetrations of intermittent renewable energy sources, might lead to the growth of pathogenic bacteria within hot water tanks. The objective of the work discussed in this thesis was to understand the extent to which there is a conflict between thermal stratification and bacterial growth in practice, whether this conflict can be resolved and the potential implications for electric hot water tanks operating on a time of use tariff. A small field study demonstrated that there is prolific bacterial growth within conventional electric cylinders and that this can be attributed to thermal stratification with a confidence of (P<0.01). Fitting a de-stratification pump, to enhance sanitary performance, resulted in a 19% decrease in the recovery of useable hot water above 43°C. Given that the tanks tested during the field study were made of copper, the consequences of alternative material choices on thermal performance were explored. It was found that the rate of useable hot water loss, due to de-stratification associated with thermal diffusion across the thermocline, could be reduced by a factor of 2.7 by making the tank liner wall from stainless steel instead of copper. Further numerical work indicated that this improvement in stratifying performance was most significant for small tanks with high aspect ratios. In addition to de-stratification that arises due to vertical conduction, de-stratification due to inlet mixing was reduced by up to 30% by installing a spiral diffuser into the base of a test cylinder. In addition, by lowering the immersion heating element to ensure there is sufficient heat transfer to the base of the cylinder, sterilising temperatures could be attained throughout the stored volume of water in the tank during heating. This showed that the conflict between thermal and sanitary performance within electric tanks could potentially be resolved. A bespoke tank, made from stainless steel and fitted with a diffuser, was built and subjected to typical draw cycles that reflect real world operation. These tests showed that more useable hot water could be delivered in comparison to a commercial off the shelf copper tank and consequently the utilisation of the Economy 7 time of use tariff would be enhanced.

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33

Gunnarsson, David. "Business strategies for the district heating sector in southern Sweden". Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105731.

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The heat demand in Sweden has stagnated and district heating companies must take action to sustain in the market. Based on this background this study combines a PEST and SWOT analysis to produce a basis to suggest general strategies suitable for district heating companies in southern Sweden. The analysis found that both investments into activities outside of the heating market, as well as further development of current systems, are viable options. Increasing the awareness and knowledge about district heating companies was also identified as a factor that could entail several benefits.

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34

Lundström, Lukas. "Heat demand profiles of buildings' energy conservation measures and their impact on renewable and resource efficient district heating systems". Licentiate thesis, Mälardalens högskola, Framtidens energi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-31495.

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Increased energy performance of the building stock of European Union is seen as an important measure towards mitigating climate change, increasing resource utilisation efficiency and energy supply security. Whether to improve the supply-side, the demand-side or both is an open issue. This conflict is even more apparent in countries such as Sweden with a high penetration of district heating (DH). Many Swedish DH systems have high share of secondary energy resources such as forest industry residuals, waste material incineration and waste heat; and resource efficient cogeneration of electricity in combined heat and power (CHP) plants. When implementing an energy conservation measure (ECM) in a DH connected building stock, it will affect the operation of the whole DH system. If there are CHP plants and the cogeneration of electricity decreases due to an ECM, and this electricity is valued higher than the fuel savings, the consequences of the ECM would be negative. These complex relationships are investigated by conducting a case study on the Eskilstuna DH system, a renewable energy supply system with relatively high share of cogenerated electricity. Heat demand profiles of ECMs are determined by building energy simulation, using recently deep energy retrofitted multifamily buildings of the “Million Programme”-era in Eskilstuna as model basis. How implementing ECMs impact on the DH system’s heat and electricity production under different electricity revenue scenarios has been computed and evaluated in terms of resource efficiency and CO2 emissions. The results show that different ECMs in the buildings impact differently on the DH system. Measures such as improved insulation level of the building’s envelope, that decrease the heat demand’s dependence to outdoor temperature, increase the amount of cogenerated electricity. While measures such as thermal solar panels, which save heat during summer, affects the absolute amount of cogenerated electricity negatively. Revenues from cogenerated electricity influence the amount of cost-effectively produced electricity much more than the impact from ECMs. Environmental benefits of the ECMs, measured in CO2 emissions and primary energy consumption, are quite small in DH systems that have high share of forest residual fuels and electricity cogeneration. The consequences can even be negative if ECMs lead to increased need of imported electricity that is produced resource inefficiently or/and by fossil fuels. However, all studied ECMs increase the relative amount of cogenerated electricity, the ratio between amount of cogenerated electricity and the heat load. This implied that all ECMs increase the overall efficiency of the Eskilstuna DH system.

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35

Seck, Gondia Sokhna. "Modélisation prospective de l'industrie diffuse pour l'évaluation de l'impact de politiques de Maîtrise De l'Énergie (MDE) à partir du générateur de modèle TIMES : la récupération de chaleur par Pompes à Chaleur (PAC) dans l'industrie agroalimentaire". Thesis, Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0001/document.

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L'augmentation des prix de l'énergie due à la raréfaction des énergies fossiles et la prise en compte des impacts environnementaux rend inéluctable l'engagement des industriels dans une démarche de maitrise de leurs consommations énergétiques et leurs émissions. L'Industrie Diffuse (ID), par opposition aux IGCE, est de plus en plus importante sur le plan économique, énergétique et environnemental. Elle devient ainsi une cible prioritaire d'autant plus que l'on constate qu'elle a été peu traitée dans les analyses énergétiques malgré l'intérêt des politiques en matière d'efficacité énergétique et le nombre considérable d'articles et de livres sur l'énergie. Comment quantifier alors l'implication de l'ID dans la contrainte réglementaire liée au changement climatique ? Quelles technologies et politiques à mettre en œuvre pour contribuer aux objectifs fixés par les plans d'actions pour l'efficacité énergétique ?Le travail de cette thèse repose ainsi sur une optimisation technico-économique de la chaine énergétique, à partir du modèle « bottom-up » de TIMES, dans une approche prospective pertinente des conséquences énergétique et environnementale de politiques MDE dans l'ID. Ce modèle s'appuie notamment sur une représentation par usages à l'inverse des IGCE du fait de l'inadaptabilité de l'approche produit/procédé. Dans ce cadre, l'analyse de la valorisation de la chaleur perdue en sortie des procédés à travers le déploiement de PAC dans l'agroalimentaire a été réalisée.Le recours à la modélisation prospective permet notamment d'observer le profil technologique et le timing des investissements des PAC en réponse à des contraintes énergétiques ou de mesures incitatives dans le cadre de Certificat d'Économie d'Énergie ou de valorisation des émissions de CO2. Il peut mettre aussi en lumière, d'une part, une possibilité d'étude sur un ajustement incrémentiel d'une taxe sur les émissions par les autorités de régulation pour atteindre leurs objectifs environnemental et énergétique sur le court, moyen et long-terme. D'autre part, il constitue un bon outil d'aide à la décision en déterminant des coûts différenciés d'économies d'énergie dans le cadre d'investissements de technologies MDE pour un meilleur criblage sectoriel
The growing energy prices due to the rarefaction of the fossil fuels and the consideration of the environmental impacts makes inevitable the involvement of industrials to promote energy efficiency policy and emissions reductions. We notice that the Non-energy intensive industry (NEI), by opposition to the energy intensive industry (EI), is expected to play an important role because of their economic and energy importance and its relatively high growth rate. It becomes then a priority target especially since it has been neglected in energy analysis despite the continuing policy interest in energy efficiency and the many reports and book written on the topic. How can NEI contribute effectively to the reduction of the energy consumptions and the CO2 emissions? Which technologies and/or policies should be implemented to reach these objectives?This PhD work is then based on a technical economic optimization of the sectoral energy system, by using a “bottom-up” model with TIMES framework, in a relevant prospective approach of the energy and environmental consequences of MDE policies in NEI. This model relies on a representation by energy end-uses contrary to the EI because of the unsuitability of the approach product/process. As part of this, we analyzed the industrial heat recovery on processes through the deployment of HP in Food & Drink industry, the most important NEI's sector.Then, this prospective modelling allows observing the shape of investments of HP in response to energy constraints or incentive policies within the mechanism of Energy Savings Certificate or valuation of CO2 emissions. It can give, on one hand, a possibility of study which giving the different adjustment of a tax on gas emissions by the authorities of regulation to reach their environmental and energy objectives in NEI over a medium or long-term horizon. On the other hand, it is very useful as a good decision-making tool by determining differentiated costs for energy savings within the investments of efficient technologies at the highest level of disaggregation for a better sectoral screening

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Vuillecard, Cyril. "Méthode de construction d’une offre d’effacement électrique basée sur les technologies gaz naturel : Application - micro-cogénération et chaudière hybride". Thesis, Paris, ENMP, 2013. http://www.theses.fr/2013ENMP0008/document.

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La thèse répond à deux problématiques, d'une part la quantification des effacements de consommation d'électricité par technologies gaz dans l'habitat et d'autre part de l'intégration de leurs valorisations dans une perspective de planification des infrastructures. Ces travaux se justifient dans un contexte d'augmentation de la pointe électrique, à l'origine d'une hausse du risque de défaillance du système, et de la baisse des consommations de gaz naturel conduisant à une sous utilisation du réseau de distribution. Pourtant, alors que la demande en gaz naturel croît du fait de l'installation de centrales à cycle combiné sur le réseau de transport, l'interaction des réseaux de distribution gaz/électricité n'est pas exploitée.Ce manuscrit envisage l'intégration des technologies gaz comme moyen de Maîtrise de la Demande en Électricité dans le processus de planification des réseaux. Ainsi les effacements de consommations d'électricité lors des périodes dimensionnantes par des micro-cogénérateurs ou des chaudières hybrides sont des solutions alternatives aux solutions de renforcement de réseaux.Pour quantifier le gisement d'effacement, nous nous intéressons à l'impact marginal des systèmes sur la demande en termes de modification de la quantité d'Énergie Non Distribuée potentielle. Les estimations des impacts de systèmes de chauffage sur la demande sont donc des prérequis à cette approche. Nous modélisons les courbes de charge régionales par une approche Bottom-Up permettant de déterminer les profils de demande marginale de chauffage en fonction des systèmes. La mise en application de cette méthode est à fiabiliser par des études socio-technico-économiques permettant de réduire les incertitudes sur les déterminants des besoins de chauffage. Une calibration en puissance des profils générés a été proposée mais n'a pu être réalisée. En revanche, nous apportons une contribution à l'analyse des courbes de charge agrégées en montrant que le modèle d'estimation actuellement utilisé par le gestionnaire de réseau s'apparente à un modèle simplifié de bâtiment
This PhD thesis addresses two issues: Firstly, the assessment of Demand Side Management (DSM) opportunity of gas and electricity technologies in dwellings, and secondly, the integration of their valuations in infrastructure planning schemes.This work originaites from a context of the growth of electricity peaks (which increased risk of system failure) and the natural gas consumption decrease which leads to an under-utilization of the gas distribution network.This manuscript focuses on the integration of gas technologies as DSM solution to contribute to the planning of electricity grid. Indeed, relieving the electricity consumption during constrained periods by diffusing micro-cogeneration or hybrid boiler, is an actual alternative to network reinforcement solutions. To quantify the load shedding capacity, we are interested in the marginal impact of demand systems on the amount of Energy Not Supplied potential. Estimating systems' impacts on heating demand is a prerequisite to this approach. So we model the regional heating load curves by a Bottom-Up approach to simulate marginal demand profiles depending on heating systems. The implementation of this method requires socio-technico-economic studies to reduce uncertainty of the determinants of heating needs. A load calibration methodology has been proposed but has not been performed. However, we make a contribution to the analysis of aggregated load curves emphasizing that the load model currently used by network operator similar to a simplified building model

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Ko, Hsin-Ting. "Techno-economic analysis of demand flexibility from heat pumps for multi-family buildings in Sweden based on two case studies". Thesis, KTH, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-272472.

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Sweden is undergoing energy transition to become a zero-carbon economy with electricity production aims at 100% from renewable resources by 2040. Sweden also has a national goal to have fossil-free vehicle fleet by 2030. The increasing share of intermittent renewable resources creates growth in mismatches between electricity supply and demand. Demand flexibility provides solution to imbalances in power system where the prosumers can regulate their energy consumption. Demand response (DR) mechanism could be beneficial to power gird stability. Electric heat pumps serve as a pool of flexible load meanwhile the thermal inertia of the residential buildings serves as thermal energy storage. In this thesis, a techno-economic analysis of demand flexibility from heat pumps for residential buildings located in central Örebro is carried out with assistance of building energy simulations. This thesis aims to improve the intelligence of this existing buildings by comprehending the size of thermal inertia availability according to different heat demand, building envelope materials, ventilation systems, weather conditions and user behaviors. Two multi-family residential buildings, Klockarängsvägen and Pärllöken, are selected for case study and compared in terms of thermal inertia and avoided peak power fees in avoided peak power fee from flexible heat pump loads. Both buildings use heat pumps for space heating and domestic hot water supply. Electricity billings are subscribed to power tariff scheme, which makes peak power shifting more profitable. On the coldest day scenario when the ambient temperature is -20°C, Pärllöken’s indoor temperature drops from 21°C to 19.1°C if heat pump is turned off for an hour. Klockarängsvägen’s indoor temperature drops from 21°C to 16.6°C if heat pump is turned off for an hour. At the lowest indoor temperature setpoint of 18°C, Pärllöken demonstrates a maximum power-shift capacity of 25 kW and heatshift capacity of 75 kWh on the coldest day. That of Klockarängsvägen is a maximum power-shift capacity of 20 kW and heat-shift capacity of 20 kWh. With larger building thermal inertia and more power-shift capacity, Pärllöken is undoubtedly the winner thanks to concrete wall materials, heavier building thermal mass, balanced ventilation, heat recovery system, and higher window class. In economic analysis, based on the proposed energy models, two control strategy options in Pärllöken are considered. Economic analysis focuses on winter season from October to March. Option 1 operates heat pump in variable capacity control mode at part load capacity. Option 2 operates in fixed capacity on/off -4- control. In winter season, Pärllöken saves 1 646 SEK in Option 1 and 2 273 SEK in Option 2. Klockarängsvägen only considers Option 1 for economic analysis, which results in 20 948 SEK avoided peak power fee. Option 2 for Klockarängsvägen exceeds indoor temperature setpoint very quickly mainly due to poorer building envelope insulation in which conserves lower thermal inertia.
Sverige genomgår en energitransformation för att bli en fossilfri ekonomi som siktar på att ha en elproduktion från 100% förnybara resurser år 2040. Sverige har också ett nationellt mål att ha en fossilfri fordonsflotta till 2030. Den ökande andelen av intermittenta förnybara resurser bidrar till ökning av obalans mellan produktion och efterfråga av elektricitet. Efterfrågeflexibilitet ger en lösning på problemet med obalanser i energisystemet där prosumenter kan reglera sin energiförbrukning. Efterfrågeflexibilitet kan vara fördelaktigt för kraft- och nätstabilitet. Elektriska värmepumpar kan agera som en stor flexibel last samtidigt som fastighetens termiska tröghet fungerar som värmeenergilagring. I denna avhandling utförs en teknisk-ekonomisk analys av efterfrågeflexibilitet från värmepumpar för två bostadshus beläget i centrala Örebro med hjälp av energisimuleringar av fastigheten. Genom denna avhandling syftar författaren på att höja intelligensen av de befintliga fastigheterna genom att undersöka storleken av den termiska trögheten som finns tillgänglig med avseende på olika värmescenario, byggnadsmaterial, ventilationssystem, väderförhållanden och användarbeteenden. Två flerfamiljshus, Klockarängsvägen och Pärllöken, väljs för jämförelse med avseende på den termisk tröghet som bidrar mest till efterfrågeflexibiliteten. De två utvalda fastigheterna använder värmepumpar för värme och varmvatten. Båda fastigheterna faktureras enligt effektabonnemang, vilket gör effektutjämning mer lönsamt. I det kallaste scenariot, när omgivningstemperaturen är -20°C, faller Pärllökens inomhustemperatur från 21°C till 19,1°C och Klockarängsvägens inomhustemperatur sjunker till 16,6°C om värmetillförseln stängs av i en timme. Under det lägsta börvärdet för inomhustemperatur på 18°C visar Pärllöken en maximal effektförskjutningskapacitet på 25 kW och för Klockarängsvägen-byggnader 20 kW. Med hänsyn till fastighetens termiska tröghet är Pärllöken utan tvekan vinnaren på grund av betong som väggsmaterial, högre termisk massa, balanserad ventilation, värmeåtervinningssystem och högre energiklass på fönsterglasen. Ovanstående skäl gör att Pärllökens termiska tidskonstant är minst tre gånger längre innan temperaturen når det lägsta börvärdet på 18°C, jämfört med Klockarängsvägen. Detta ger att Pärllöken har en högre förskjutningskapacitet av värme på 75 kWh jämfört med Klockarängsvägens maximala förskjutningskapacitet på 20 kWh. I en ekonomisk analys, baserat på författarens framtagna energimodeller, beaktas två styrstrategier i Pärllöken. Den ekonomiska analysen fokuserar på vintersäsongen från oktober till mars. Alternativ 1 driver värmepumpen med partiell kapacitet enligt reglerbar effekt. Alternativ 2 stänger av värmepumpen helt. Under vintersäsongen sparar Pärllöken 1 646 SEK med Alternativ 1 och 2 273 SEK med Alternativ 2. Klockarängsvägen använder sig endast av Alternativ 1 för en ekonomisk analys, vilket resulterar i en kostnadsbesparing på 20 948 SEK. En förstudie med värmepump i kombination med andra förnybara tekniker så som solceller på Klockarängsvägen genomförs för att undersöka potentialen av energibesparing. Kombinationen ger dock inte en positiv effekt på grund av den låga solinstrålningen under vintertid.

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Nel, Leon Martin. "A demand side management study model for an on–off heap leach pad / Nel L". Thesis, North-West University, 2011. http://hdl.handle.net/10394/7267.

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In today’s world it is imperative to understand that the power demand of industrial and mining operations should be as economical as possible. This is especially necessary with the inevitable depletion of our natural recourses such as coal, oil and gas which is used in the production of electricity. Since no replacement is currently available for carbon based electricity in Southern Africa, there is significant pressure applied by utility suppliers to force consumers to use energy wisely. The challenge is to run plants as efficiently as possible by decreasing operation’s electrical footprint. High electrical costs and tariffs are the next primary driver for plant owners to use electricity efficiently. Whether applying for allocation of power to a local electricity supplier, designing for optimisation of capital and operation expenditures, managing operation peak demands or for all of the above, a consumer must have a method of evaluating the plant’s demand side demand. Demand side consumption is the energy consumed by the consumer at the tie–in point to the supplier and is represented by a load shape. A study on how to reduce the demand of electrical energy consumed by the consumer at this interface is called a demand side management study or DSM study. A DSM study is part of a DSM process. On existing plants where stakeholders would like to know their demand side consumption or load shape in order to implement a DSM process, measurements can be taken at the tie–in point (or also referred to as the point of interest). The question arises, what about clients that would like to conduct a DSM study (or the entire DMS process) on a greenfield project perhaps during the feasibility phase or basic engineering phase? In both cases very little information is available. This dissertation presents a model as part of the DSM study on a uranium plant’s leaching section for the client to use in his DSM process. The specific leaching technology to which this model is applied is called an on–off heap leach pad (OOHLP). The process followed to obtain the load shape was firstly to conduct a search for other similar studies and operations in order to find useful information and techniques. The next step was to investigate and design a prototype plant based on the client’s requirements as a case study project, namely Trekkopje Maxi located in Namibia. The equipment, components and their operational profiles were identified and from this a mathematical formula was developed and a visual model was outlined. Finally the results were verified at selected points against the same calculated by an electrical software package’s load flow simulation tool. The OOHLP’s model developed in this dissertation can be used in future studies to optimize the electrical design of leach pads.
Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.

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Abíková, Klára. "Analýza možností vytápění rodinného domu". Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-197656.

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The aim of this thesis is to analyze the possibility of heating the particular house and depending on the results to recommend appropriate option resp. type of fuel needed for heating. For this reason, the paper is primarily focused on general knowledge related to the issue of heating houses, which belong types of heating systems and heating options or heat loss or heat demand for heating. After all the general knowledge is applied to a particular house, which will serve as input for the analysis. Analysis of heating the house is subsequently determined not only from a cost point of view but also from a technical point of view and the output of recommending specific options for heating the house.

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40

Campos, Fábio Angioluci Diniz. "Demanda energética em situação simulada de luta em atletas de taekwondo". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/39/39134/tde-03112011-083727/.

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O objetivo deste estudo foi investigar as contribuições dos sistemas energéticos e do gasto energético total em situação de luta. A amostra foi composta de 10 atletas do sexo masculino de nível nacional/internacional (21±6 anos; 176.2±5.3cm; 67.2±9.0kg), competindo em nível internacional. Para a estimativa das contribuições energéticas e do gasto energético total, foram realizados três protocolos simulando combate (um round, dois rounds e três rounds). As lutas foram filmadas para quantificação das ações motoras em cada round. A estimativa dos sistemas energéticos aeróbio (WAER), anaeróbio alático (WPCR) e anaeróbio lático (W[La-]) foi realizada através do consumo de oxigênio durante a atividade, do delta da concentração sanguínea de lactato de cada round e do débito alático de oxigênio (DAO2), respectivamente. A razão entre as ações de elevada intensidade e momentos de baixa intensidade (step e pausa) no protocolo 3 foi ~1:7. Os resultados dos sistemas WAER, WPCR e W[La-] no protocolo 3 foi 120±22kJ (66±6%), 54±21kJ (30±6%), 8,5kJ (4±2%), respectivamente. Assim, as sessões de treinamento devem ser direcionadas principalmente para a melhoria do sistema anaeróbio alático (responsável pelas ações de alta intensidade), e do sistema aeróbio (responsável pelo processo de recuperação entre as ações de alta intensidade)
The purpose of this study was to investigate energy system contributions and energy cost in combat situation. The sample was constituted by 10 male taekwondo athletes at national/international level (age: 21±6 years old; height: 176.2±5.3cm; body mass: 67.2±9.0kg) competing at national/international level. To estimate the energy contributions and total energy cost of the fights, athletes performed a three different protocols simulated competition (1 round, 2 rounds and 3 rounds). The combats were filmed in order to quantify the actual time spent fighting in each round. The estimate of the aerobic (WAER), anaerobic alactic (WPCR) and anaerobic lactic (W[La-]) energy systems was carried out through the oxygen consumption during the activity, the fast component of excess post-exercise oxygen consumption, and the delta of blood lactate concentration in each round, respectively. The mean data between the high intensity actions and moments of low intensity (step and pause) was ~1:7. The results of WAER, WPCR and W[La-] system contributions were 120±22kJ (66±6%), 54±21kJ (30±6%), 8,5kJ (4±2%), respectively. Thus, training sessions should be directed mainly to the improvement of the anaerobic alactic system (responsible by the high-intensity actions), and of the aerobic system (responsible by the recovery process between high-intensity)

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41

Björnberg, Inez y Anita Tarus. "Off-Grid Tiny Housing : An Investigation of Local Sustainable Heat and Power Generation for an Artificial Island in Stockholm". Thesis, KTH, Energiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299849.

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A growing world population has resulted in an increasing number of people being homeless or living in inadequate housing. In addition, the threatening climate crisis and the world’s limited resources calls for a more sustainable way of living. The organization Stockholm Tiny House Expo aims to contribute a solution to these issues: an artificial island with several tiny houses, able to adapt to rising sea levels, having net-zero-waste and completely self-sufficient regarding energy. This island will symbolize the sustainable development goals and will be an attraction for tourists, as well as create several job opportunities. In order to realize this vision, research needs to be conducted to find solutions to make this island become reality. Therefore, the aim of this project is to evaluate the economic and environmental feasibility of a high degree of self-sufficiency regarding energy, by locally producing heat and power, on an artificial island in Stockholm. Firstly, a literature review is conducted to find suitable technologies to supply the island with heat and power. Subsequently, the software tools IDA ICE and HOMER Pro are used to simulate the energy demand and supply of the island. Eight different scenarios, with different types of supply and demand, are created to investigate different possibilities of the island. The scenarios are evaluated using technical-, economic- and environmental key performance indicators. A scenario where the demand is reduced and heat and power are supplied only by resources on the island, is deemed most relevant based on Stockholm Tiny House Expo’s vision. A sensitivity analysis is therefore performed on this scenario. The results indicate technical and environmental feasibility; however, the economic evaluation showed that this scenario will be non-profitable. Although the scenario is non-profitable, if further measures are taken to create a pricing model to customers, it could be possible. In conclusion, the results of this research indicate that it is possible for Stockholm Tiny House Expo to be self-sufficient regarding heat and power solely utilizing renewable energy. The evaluation of the results, however, showed that it is not economically feasible. In addition, the national grid did not contribute to an impact on the surrounding environment, nor to a considerable amount of greenhouse gas emissions. Hence, grid connection is recommended for Stockholm Tiny House Expo.
En växande världspopulation har resulterat i att ett ökande antal människor är hemlösa eller bor i bristfälliga bostäder. Den hotande klimatkrisen och jordens begränsade tillgångar kräver dessutom en hållbarare livsstil. Organisationen Stockholm Tiny House Expo vill bidra med en lösning till dessa problem: en artificiell ö med flera småhus, som kan anpassa sig till stigande havsnivåer, har noll nettoavfall och är helt självförsörjande gällande energi. Denna ö kommer symbolisera FN:s hållbarhetsmål och vara en turistattraktion så väl som skapa ett flertal arbetsmöjligheter. För att förverkliga denna vision krävs forskning för att hitta lösningar och göra denna ö till verklighet. Därmed är syftet med detta projekt att undersöka den ekonomiska och miljömässiga genomförbarheten av en hög grad av självförsörjning av energi, genom att lokalt producera kraft och värme, på en artificiell ö i Stockholm. Först utförs en litteraturstudie för att hitta lämpliga teknologier för att försörja ön med kraft och värme. Därefter används programvarorna IDA ICE och HOMER Pro för att simulera energibehovet och energiförsörjningen för ön. Åtta olika scenarier, med olika typer av försörjning och behov, konstrueras för att undersöka olika möjligheter för ön. Scenarierna utvärderas med hjälp av tekniska-, ekonomiska- och miljömässiga nyckeltal (key performance indicators). Ett scenario där behovet är reducerat samt att kraft och värme endast försörjs av resurser på ön, bedöms vara mest relevant baserat på Stockholm Tiny House Expos vision. En känslighetsanalys utförs därför på detta scenario. Resultaten tyder på att scenariot är tekniskt och miljömässigt genomförbart; dock visade den ekonomiska utvärderingen att det inte är lönsamt. Trots detta så skulle det kunna vara möjligt om vidare åtgärder tas för att skapa en prissättningsmodell mot kunderna. Sammanfattningsvis så tyder resultaten på att det är möjligt för Stockholm Tiny House Expo att vara självförsörjande gällande kraft och värme som endast utnyttjar förnybar energi. Utvärderingen av resultatet visade dock att det inte är ekonomiskt genomförbart. Det nationella kraftnätet bidrog dessutom inte till påverkan på den omgivande miljön och inte heller någon betydande mängd växthusgasutsläpp. Följaktligen rekommenderas nätanslutning för Stockholm Tiny House Expo.

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42

Quiggin, Daniel. "Modelling the expected participation of future smart households in demand side management, within published energy scenarios". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16220.

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The 2050 national energy scenarios as planned by the DECC, academia and industry specify a range of different decarbonised supply side technologies combined with the electrification of transportation and heating. Little attention is paid to the household demand side; indeed within many scenarios a high degree of domestic Demand Side Management (DSM) is implicit if the National Grid is to maintain supply-demand balance. A top-down, bottom-up hybrid model named Shed-able Household Energy Demand (SHED) has been developed and the results of which presented within this thesis. SHED models six published national energy scenarios, including three from the Department for Energy and Climate Change, in order to provide a broad coverage of the possible energy scenario landscape. The objective of which is to quantify the required changes in current household energy demand patterns via DSM, as are implicit under these highly electricity dominated scenarios, in order to maintain electrical supply-demand balance at the national level. The frequency and magnitude of these required household DSM responses is quantified. SHED performs this by modelling eleven years of supply-demand dynamics on the hourly time step, based on the assumptions of the published energy scenarios as well as weather data from around 150 weather stations around the UK and National Grid historic electricity demand data. The bottom-up component of SHED is populated by 1,000 households hourly gas and electricity demand data from a recently released dataset from a smart metering trial in Ireland. This aggregate pool of households enables national domestic DSM dynamics to be disaggregated to the aggregate household level. Using household classifications developed by the Office for National Statistics three typical ' households are identified within the aggregate pool and algorithms developed to investigate the possible required responses from these three households. SHED is the first model of its kind to connect national energy scenarios to the implications these scenarios may have on households consumption of energy at a high temporal resolution. The analysis of the top-down scenario modelling shows significant periods where electrical demand exceeds supply within all scenarios, within many scenarios instances exist where the deficit is unserviceable due to lack of sufficient spare capacity either side of the deficit period. Considering the level of participation required within the modelled scenarios in order to balance the electricity system and the current lack in understanding of smart metering and Time-Of-Use (TOU) tariffs within households, it would seem there is a disconnect between the electricity system being planned, the role this system expects of households and the role households are willing to play.

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43

Driscoll, Annelise. "DEMAND STUDY FOR DENTAL HYGIENE BACHELOR DEGREE PROGRAM". Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2826.

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The following is a study to determine if sufficient demand exists to start a Bachelor of Science and Master of Science degree program in dental hygiene through a joint agreement for completion degrees between Valencia Community College and the University of Central Florida. To accomplish this objective two survey instruments were administered to randomly selected licensed dentists and dental hygienists in the state of Florida. Dental hygienists represented the potential student base for the proposed programs, and dentists represented the potential and prospective employers of graduated students of the proposed programs. To determine demand and demand characteristics, one survey instrument was mailed to 1,000 dental hygienists who were randomly selected using SAS software from a population of N=12,066 dental hygienists actively licensed to practice in the state of Florida. This sample of hygienists was approximately 8.3% of the total population. Of the 1,000 samples, 134 (or 13.4%) were returned. Of the 134 surveys returned, 123 (n=123) were included in this study. Eleven surveys were not included because of a majority of missing data or because the respondent indicated he or she already possessed a Bachelor or Master degree. A Likert-scale questionnaire was sent to each group of actively licensed dentists and actively licensed dental hygienists from the state of Florida. Responses from dental hygienists were overwhelmingly positive towards the addition of the Bachelor of Science degree program with an online distance-learning component. Those in favor of the Bachelor of Science degree program also provided a favorable response towards adding a Master of Science degree program in dental hygiene. The dentists, as potential future employers, also showed strong support in their responses for the additional degree programs with an additional management track component and believed it would elevate the professional standards of the dental hygiene field.
Ph.D.
Department of Health Professions
Health and Public Affairs
Public Affairs PhD

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44

Reis, Max Mauro Lozer dos 1986. "Comparação das eficiências energéticas entre sistemas de bombas de calor para atendimento às demandas de ar condicionado e aquecimento de água em edifício". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265895.

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Orientador: José Ricardo Figueiredo
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-25T20:30:12Z (GMT). No. of bitstreams: 1 Reis_MaxMauroLozerdos_M.pdf: 8423703 bytes, checksum: 5b452213e84aa4386f6d9f3291cae840 (MD5) Previous issue date: 2014
Resumo: Neste trabalho foi realizado um conjunto de simulações numéricas de diferentes sistemas de bombas de calor em diferentes condições de funcionamento, para atender simultaneamente às demandas do ar condicionado e do consumo de água quente em edifício. Foram consideradas na proposta deste trabalho duas máquinas independentes, uma bomba de calor responsável pelo aquecimento e um ciclo de refrigeração para resfriamento da água. Além disso, foi investigado a possibilidade de empregar os efeitos de aquecimento e resfriamento de uma única bomba de calor padrão, duas bombas de calor em cascata e um sistema com dois estágios de compressão com separador de gás flash. Para estas alternativas fez-se necessária a complementação da energia térmica através de uma bomba de calor auxiliar para atender a demanda total de água quente e fria e os desempenhos dos sistemas de bombas de calor foram comparados através de uma análise energética. Um programa em ambiente MATLAB® foi desenvolvido e envolveu relações termodinâmicas e de transferência de calor para os sistemas de bombas de calor e sistema de distribuição de água quente e fria para o edifício, a fim de aproximar o funcionamento dos sistemas reais. Utilizaram-se ferramentas como o método de Substituição-Newton-Raphson, para a solução dos problemas em regime permanente, e que também foi utilizado juntamente com o método de Euler para resolução em condições variáveis ao longo de 24 horas. Os resultados confirmaram a viabilidade energética ao utilizar bombas de calor, podendo obter para o efeito de aquecimento de água uma economia de até 72% no consumo de energia elétrica, quando comparado ao chuveiro elétrico. Através dos resultados também foi possível observar que o sistema de bomba de calor com separador de gás flash desempenha sua função de forma mais eficiente, energeticamente, quando comparado ao sistema padrão e em cascata
Abstract: In this work it was realized a set of numerical simulations of different heat pump systems in different operation conditions to meet simultaneously the demands of air conditioning and hot water consumption in a building. It was considered in propose this work two independent machines, a heat pump responsible for heating and a refrigeration cycle responsible for cooling water. Moreover, it was explored the possibility to employ the both effects, heating and cooling, of a standard heat pump, two heat pumps in cascade and a system with two compression stages with a flash gas separator. For the last alternatives it was necessary complementary thermal energy through an auxiliary heat pump to meet the total demand of hot and cool water. The performance of the heat pump systems was compared through an energetic analysis. A program in MATLAB® was developed involving of thermodynamic and heat transfer relations for the heat pumps and water distribution systems in the building with purpose to approach the real system operation. Moreover, the method Substitution-Newton-Raphson was used to solve the problems in steady state and this method together with Euler method were used to solve in variable conditions throughout 24 hours of the day. The results confirmed the energetic feasibility using heat pump systems. These systems will be able to save up to 72% in energy consumption using heating effect comparing to an electric shower. Furthermore, the system with flash gas separator it works of more way energetically efficient than other systems as a standard and a cascade systems
Mestrado
Termica e Fluidos
Mestre em Engenharia Mecânica

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45

Bernard, Richard. "An examination of a non-managerial internal labour market in a corporate head office : a case study". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61942.

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46

Zhang, Lingxi. "Techno-economic and environmental assessment of a smart multi-energy grid". Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/technoeconomic-and-environmental-assessment-of-a-smart-multienergy-grid(c517bfe4-585e-4d49-bafb-d97dbfc15aa9).html.

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This PhD thesis proposes a bottom-up approach that accurately addresses the operational flexibility embedded in each part of a multi-energy system (MES). Several models which cover the simulations from replicating domestic electrified demands to power system scheduling are proposed. More specifically, a domes-tic multi-energy consumption model is firstly developed to simulate one minute resolution energy profiles of individual dwellings with the installation of prospec-tive technologies (i.e., electric heat pumps (EHPs), electric vehicles (EVs)). After-wards, a fast linear programming (LP) unit commitment (UC) model is devel-oped with the consideration of characteristics of generators and a full set of ancil-lary services (i.e., frequency response and reserves). More importantly, the fre-quency response requirements in low inertia systems are assessed with the con-sideration of three grid frequency regulations (i.e., rate of change of frequency, Nadir and quasi-steady state). Furthermore, the UC model has integrated vari-ous flexibility contributors in MES to provide ancillary and flexibility services, which include pumped hydro storages (PHSs), interconnectors, batteries and demand side resources (i.e., individual EHPs, heat networks, electrolysers). More importantly, the fast frequency response (FFR) provision from nonsynchronous resources is implemented and the demand response application of electrolysers is taken as an example to provide FFR in the UC model. By using the integrated UC model with the consideration of flexibility services provided by resources in the MES, the advantages of multi-energy operation can be clearly identified which can be used to inform system operators and policy makers to design and operate energy systems in a more economic and environment-friendly way.

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47

Lumbier, Fernandez Mikel. "Alternative energy supply study for a cottage in Vifors". Thesis, Högskolan i Gävle, Energisystem, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-26714.

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The present master thesis was done during the spring of 2018. A cottage located in Vifors is studied with regard to its heating requirements. At the time of the study, the house could not be inhabited the whole year because there was no tap hot water available and the space heating demand was covered by electricity. Thus, an alternative heating supply is required to be developed. As a strategic prerequisite, the solution should be achieved considering both solar thermal collectors and a heat pump.First, the characteristics of the building were collected/determined in order to obtain the total heating demand per month and hence annually. Parameters such as the U-values, roof orientation, room dimensions, ventilation rates and internal gains were required to configure the building model in the software IDA ICE 4.8. In addition, the amount of tap hot water required per year was determined as 17 m3 per year. Cold water at 5 °C had to be heated until 55 °C to obtain the tap hot water.Once the heating requirements were known, the most suitable solution was to use a combi system (solar thermal collectors and a heat pump). Solar energy could fulfil the demand in the summer and the heat pump provided energy in the winter. For a commercial model of the flat solar thermal collector (Vitosol 100-F) the solar system was sized according to the heating demand in the summer time. The maximum energy that could be obtained from the solar collectors in summer was calculated, the rest of the demand had to be fulfilled by a heat pump, model WPL-18 E.The achieved solution is compounded by the heat pump and 3 solar thermal collectors with a surface of 2.33 m2 each. The solar energy obtained is 1 843 kWh per year, which covers 9 % of the total annual heating demand (20 098 kWh). However, the 98 % of the heating demand during the summertime comes from the solar collectors. The investment cost is 113 900 SEK and the payback period is estimated in 8 years.

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48

Gyamfi, Seth. "Considerations and Development of a Ventilation on Demand System in Konsuln Mine". Thesis, Luleå tekniska universitet, Geoteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80985.

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Ventilation on demand (VOD) concept has earned significant worldwide attention by several mining companies in recent years. It is a concept where airflow is provided only to areas that require ventilation. The implementation of the concept has resulted in significant savings in annual energy consumption and cost for several companies globally. The research presented in this thesis sought to present the VOD system as an alternative solution and strategy to improve the ventilation system of Konsuln mine. The system is expected to cope with a planned increase in production rate and meet requirements in the new Swedish Occupational Health & Safety (OH&S) regulations, Arbetsmiljöverkets förtfattningssamling (AFS) 2018:1, which is based on the EU directive 2017/164 where Threshold Limit Value (TLV) for gases have been significantly reduced and provide safe work environment for workers in the mine. The thesis work started with planning and execution of a PQ (Pressure – Quantity) survey to calibrate the existing ventilation model of Konsuln mine. This was to ensure that the model is reasonably accurate to give reliable simulation predictions of the performance of Konsuln ventilation system in its current state and for the future. The good correlation between the modelled and underground measured values validated the model for further ventilation planning. The study further investigated and analyzed the current and future ventilation demand of LKAB test mine, Konsuln, to design a VOD system for its operations.The work outlined three main VOD design scenarios I, II, and III based on the proposed production plan, schedule, and the mining process that present the underground working conditions on the three main levels (436, 486 and 536) of Konsuln mine. Diesel, battery-powered, heat, and blast simulations were carried out for all the scenarios in the calibrated ventilation model using VentSim Design simulation software. The model was again used to estimate the annual ventilation power cost for the VOD scenarios to highlight the benefit and cost savings advantage under the VOD design system to deliver enough airflow quantity compared to the conventional system of ventilation. Simulation results showed that about 15.6% – 49.1% and 76.4% - 86.7% of significant cost savings will be achieved for diesel and battery-powered machineries respectively, while still supplying the needed amount of air to working areas to keep contaminants below their Threshold Limit Value -Time Weighted Average (TLV-TWA) and provide a good working environment. For additional benefits and savings of the Ventilation on Demand (VOD) system implementation, some considerations for equipment, personnel positioning and identification, monitoring system, and stations have also been discussed in this work. These include; (i) Utilization of LKAB’s database system, Giron, in addition to mounting tags with unique IDs on machineries, to track the route of LHDs and trucks to deal with the challenge of airflow supply shortfall associated with auxiliary fans adjustment to affect target locations. (ii) Installation of temperature sensors, flow meters, gases and Diesel Particulate Matter (DPM) monitoring systems at specific, appropriate, and optimal locations in the mine for efficient implementation of the VOD system strategy. The heat simulations for both diesel and battery-powered machineries were carried out for the month of July when the highest temperatures in Kiruna are often recorded for the summer. They predicted the highest temperatures in working areas to be well below the limit used in Australia, 28°C Wet Bulb (WB). Four scenarios A, B, C and D were also considered for blast clearance time simulation using both the ramp and exhaust shaft. The blast simulation results indicated that the time to dilute and clear blast fumes through the exhaust shaft saves some clearance time compared to exhaustion through the ramp, although the shaft exhaustion will require additional financial commitment to purchase and install exhaust fans on each of the three main levels of the mine. Nevertheless, major ventilation work and practices such as removal of regulator in front of primary fans, additional radon measurement, and good auxiliary ventilation practices have been recommended to improve and actualize the benefits outlined in this work.

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49

Yaser, Hussnain A. "Novel System Design For Residential Heating And Cooling Load Shift Using PCM Filled Plate Heat Exchanger And Auxiliaries For Economic Benefit And Demand Side Management". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397234246.

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Lehoczky, Annamária. "Changing horizon of climate science: from scientific knowledge towards demand based, integrated climate services". Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461522.

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Els Serveis Climàtics (SC) tenen un rol addicional en la ciència del clima, amb l’objectiu de proporcionals als diferents tipus d’usuaris informació útil y processada sobre variabilitat climàtica, els impactes i riscos del canvi climàtic, així com les oportunitats i incerteses. Per tant, per reduir la distancia entre dades fiables i la seva usabilitat, la investigació de SC és de gran importància. Aquesta tesis d’investigació interdisciplinària aborda el desafiament de sintetitzar la informació climàtica. El seu objectiu general és facilitar la integració d’informació climàtica a escala regional dels SC per donar justificació a la planificació i formulació de polítiques d’adaptació al canvi climàtic. La novetat és què reflecteix l’enfoc orientat als usuaris dels SC, és a dir, a més de l’anàlisi climatològic quantitatiu, també utilitza dades socials qualitatives per entendre millor les necessitats dels professionals i acadèmics involucrats en la co-producció del coneixement relacionat amb el clima. Aquesta tesis utilitza diversos conjunts de dades, incloent dades remotes de la temperatura de la superfície terrestre, dades meteorològiques mesurades en superfície i simulacions de temperatura obtingudes d’un model climàtic regional d’alta resolució (12.5km). Les recomanacions se suporten en l’experiència pràctica. L’estudi de cas a escala local afavoreix nous resultats sobre el risc del calor urbà a la ciutat de València. Revelant un considerable efecte d’illa de calor urbana nocturna juntament amb un confort tèrmic desfavorable a les zones densament urbanitzades. Això subratlla la necessitat d’una planificació urbana resilent amb el canvi climàtic, especialment considerant la tendència d’escalfament gradual projectada per a finals del segle XXI a tota la Península Ibèrica. Per explorar els factors que influeixen en l’eficiència de les col·laboracions transdisciplinaries en els estudis de planificació i adaptació al clima urbà, es realitzaren entrevistes amb acadèmics i professionals. Concloent que la integració de diferents disciplines i perspectives es vital per a l’eficiència dels SC. Una major compressió de les necessitats i motivacions dels actors de les comunitats científiques i professionals contribueix a millorar les prestacions dels SC.
Los Servicios Climáticos (SC) desempeñan un rol adicional en la ciencia del clima, con el objetivo de proporcionar a los diferentes tipos de usuarios información útil sobre variabilidad climática, los impactos del cambio climático y sus riesgos, así como las oportunidades e incertidumbres. Por lo tanto, para salvar la brecha entre los datos fiables y su usabilidad, la investigación SC es de gran importancia. El objetivo general de esta tesis de investigación interdisciplinaria es facilitar la integración de información climática a escala regional y local de los SC que apoye la planificación y formulación de políticas de adaptación al cambio climático. La novedad es que refleja el enfoque orientado al usuario del SC, es decir, además del análisis climatológico cuantitativo, también utiliza datos sociales cualitativos para entender mejor las necesidades de los profesionales y académicos involucrados en la co-producción del conocimiento relacionado con el clima. Esta tesis utiliza varios conjuntos de datos, incluyendo datos remotos de la temperatura de la superficie terrestre, datos meteorológicos medidos en superficie y simulaciones de temperatura obtenidas de un modelo climático regional de alta resolución (12,5 km). Las recomendaciones se apoyan en la experiencia práctica. El estudio de caso a escala local ofrece nuevos resultados sobre el riesgo del calor urbano en la ciudad de Valencia. Revelando un considerable efecto de la isla de calor urbana nocturna junto con un confort térmico desfavorable en las zonas densamente urbanizadas. Esto subraya la necesidad de una planificación urbana resiliente al cambio climático, especialmente considerando la tendencia de calentamiento gradual proyecta para finales del siglo XXI en toda la Península Ibérica. Para explorar los factores que influyen la eficiencia de las colaboraciones transdisciplinarias en los estudios de planificación y adaptación al clima urbano, se realizaron entrevistas con académicos y profesionales. Concluyendo que la integración de diferentes disciplinas y perspectivas es vital para la eficiencia de los SC. Una mejor comprensión de las necesidades y motivaciones de los actores de las comunidades científicas y profesionales contribuye a mejorar las prestaciones de los SC.
Climate Services (CS) assign an additional role to Climate Science, aiming to provide different kinds of users with usable and actionable information on climate variability, climate change impacts and its related risks, opportunities and uncertainties. Thus, to bridge the gap between reliable data and their usability, CS research is highly important. This interdisciplinary research thesis addresses the climate information distillation challenge. Its overall aim is to pave the way for the integration of regional and local climate information into CS that support climate adaptation planning and policy-making. The novelty of this thesis is that it reflects on the user-oriented approach of CS, i.e., as well as quantitative climatological analysis, it also uses qualitative social data to better understand the needs of practitioners and academics engaged in climate-related knowledge co-production. The thesis uses various datasets, including remotely sensed land surface temperature data, ground-measured meteorological data and temperature simulations obtained from a high resolution (12.5 km) regional climate model. The recommendations are supported by practical experience. The local scale case study offers valuable new insights into the urban heat hazard in the city of Valencia (Spain), revealing the considerable nighttime urban heat island effect along with unfavourable thermal comfort in the densely built-up urban areas. This underlines the need for climate-resilient urban planning, especially in light of the projected gradual warming trend over the entire Iberian Peninsula towards the end of the 21st century. To explore the factors that influence the efficiency of transdisciplinary collaborations working on urban climate adaptation and planning, in-depth interviews were conducted with academics and practitioners. This thesis demonstrated that integrating different disciplines and perspectives is vital for efficient CS. An improved understanding of the needs and motives of stakeholders from science and practice communities greatly contributes to the development of CS.

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Tesis sobre el tema "Heat demands"

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