Dissertations / Theses on the topic 'Energy efficient built environment'

The Swedish government in the 1960th initiated “The Million Program” to build million residentialunits to cover the housing shortage between 1965 to 1975. Tjärna Ängar neighborhood in Borlängemunicipality was built during the million-program period, where these residential units became old,and the indoor environment is uncomfortable for the residents.Recently, there have been extensive energy-efficient renovations to improving the energyefficiency,indoor air quality, and thermal comfort of these buildings. The renovation project, withcooperation between Dalarna University and the local housing company (Stora Tunabyggen)started in 2015 by renovating three buildings in the Tjärna Ängar neighborhood.This study was conducted at one of these three retrofitting buildings (Kornstigen 25) to investigatethe thermal comfort in the building following energy retrofit. The assessment of the thermalcomfort in this study is based on Fanger's model with the use of predicted mean vote (PMV) andpredicted percentage of dissatisfied (PPD) to assess the obtained measurements.An online questionnaire survey with building occupants was conducted to give a betterunderstanding of the current situation of the retrofitting building before and after the renovationregarding thermal comfort. Based on the measurement, the thermal sensation of the occupants isslightly cool according to the standard’s sensation scale during the period of the measurement. Anonline questionnaire survey assures that the occupants were feeling slightly cool during someperiods of the day inside the apartments.

Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, Center for Real Estate, 2008.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (leaves 79-81).
This thesis attempts to explore the relationships between the Buildings Sector, energy efficiency and global warming. Through a qualitative analysis the author illustrates the connection between these three areas and shows how both energy efficiency, as a key policy measure, and the Buildings Sector, as the key recipient of such policies, can act together to significantly mitigate the effects of global warming and resulting climate change. First, the reader is given the tools to understand the issues surrounding global warming and climate change. This is accomplished through an overview of related science, history and environmental and economic impacts. Future climate scenarios are explained and mitigation options are offered. Second, an overview of energy efficiency as the primary mitigation option for global warming is given. Terminology, history and mitigation potential of energy efficiency and how it applies across market sectors are reviewed. Barriers to implementation of energy-efficiency projects and the need for strong policy are also explored. Third, the Buildings Sector, showing the most promise for greenhouse gas mitigation through energy-efficiency investments, is analyzed. This analysis focuses on the current consumption patterns of buildings, on available energy-efficient technologies, and on the characteristics of efficiency projects in buildings and how they support the goals of broader climate change policy. The analysis concludes with a review of the barriers to such projects along with an overview of the policies in place meant to overcome these barriers. Finally, the author summarizes her research and offers her conclusions.
by Donna K. DiBona.
S.M.in Real Estate Development

Contemporary Libyan architecture has rarely recognized the local climate or renewable energy issues and these subjects are neglected or rarely studied. However, Libyan local vernacular architecture includes traditional solutions that have been tested over centuries, providing passive design for low energy consumption as well as creating architecture related to the local environment. This research aims to provide guidelines for architectures to consider how to incorporate climatic design in creating architecture related to the local environment that should provide more sustainable solutions in hot climate regions. The study uses the concept of sustainable development to offer a holistic perspective to establish a body of knowledge on passive climatic design that could benefit architects when designing future housing. According to this general understanding, this research project focuses on the interrelationship between passive climatic design and vernacular architecture in such situations. It aims to look at the theoretical and experimental studies that have demonstrated the usefulness of passive climatic design techniques in context with the cooling of buildings in hot regions in order to establish climatic design guidelines using Tripoli, Libya as the case example. The guidelines are developed for housing design, and take on board the opinions of end users and professionals as well as understanding building performance from the climatic point of view. Both deductive and inductive approaches have been selected where theoretical strategies are first confirmed from the existing literature which are then investigated using an array of appropriate methods (questionnaire, interviews and focus group as well as sampling the internal temperatures inside selected case study houses) to examine the thermal comfort in both vernacular and contemporary housing. Results are merged to produce guidelines that can help architects in terms of using climatic design principles in future housing in hot climate regions.

Retrofitting the UK domestic built environment presents an excellent opportunity to improve its energy performance. However, retrofitting homes is a complex challenge conflated by multiple factors. Due to this complexity, a shortfall exists between the full potential and realised adoption of energy efficiency measures in the UK, a phenomenon termed the ‘Energy Efficiency Gap’. While a number of technical or economic factors may help explain this gap, difficult to quantify factors, such as social motivations, barriers, and viewpoints towards energy are also significant and often under-emphasised in public policy. As such, in order to improve the understanding of the Energy Efficiency Gap and the uptake of future retrofit initiatives, this research adopted a socio-technical approach that considered social and technical retrofit factors together. Specifically, this research collected data from interviews, questionnaires, and a Q Study in the cities of Manchester and Cardiff, alongside a questionnaire that measured energy efficiency technology and behaviour preferences. An original contribution to knowledge was using the data to empirically identify motivations and barriers to adopting energy efficient technologies, as well as identifying household viewpoints towards energy use and linking them to retrofit technology and energy efficiency behaviour preferences. As a result of this research, specific policy recommendations are presented to help promote energy efficiency retrofits in the UK. This research was carried out as part of the Engineering & Physical Science Research Council and Sustainable Urban Environment research programme, “Re-Engineering the City 2020-2050 Urban Foresight and Transition Management (RETROFIT 2050)”.

he Department of Energy names executing and integrating high-performance sustainable design and green building best practices a Strategic Sustainability Performance Plan goal under the Executive Order 13514 (U.S DOE, 2009). As sustainability becomes a primary goal for engineers, a decision making framework is needed to guide their choice of materials and processes; and then to carry out the evaluation of their chosen design. Sustainable design process, and the products developed through its application, work concurrently with functionality and sustainability evaluation methodologies to cultivate a continuous loop of design, implementation, assessment and improvement. In this context, an alternative insulation prototype exploring the use of evacuated packets of pyrogenic silica substituting for conventional insulation for refrigeration applications was developed and assessed. Assessment criteria included experimental comparison of heat transfer characteristics and the energy efficiency of the new insulation as well as its life cycle as it related to environmental sustainability. Results indicate that by utilizing alternative insulation design, heat flux decreased by an average of 36%, and energy efficiency improved by 5.1% over a 24 hour period. The new insulation design also resulted in improved environmental sustainability, resulting in a savings of 0.257 metric tons of CO2e over 20 years for a single unit. Results provide an alternative insulation design for use in commercial insulation applications, and a framework by which to assess the efficiency and environmental performance of similar products.

The aim of the research is to explore the differences in final energy consumption and environmental impact of the construction materials related to the atrium alternative and a business-as-usual and evaluate how to improve thermal properties of old buildings that require renovations to fit thermal efficiency standards and comfort in operational conditions while reducing the overall impact of the projects. Results show that for the low-rise atrium most of the parameters related to the final energy demands and environmental impacts of the atrium construction materials are proportional and linear to the increase of the glazing area size. When compared to simply renovating old structures, the atrium alternative can promote a decrease in thermal losses by transmission and increase in incident solar radiation through the glazed area depending on the atrium dimensions and glazing area size. And although cooling, heating, electrical and ventilation demands are raised for the overall demand of the building the construction of an atrium bears less environmental impact than renovating old structures damaged by weather.

2021-04-08

Global warming induced by the emissions of greenhouse gases is one of the most important global environmental issues facing the world today. Using the building simulation techniques, this research investigates the interaction and relationship between global warming and built environment, particularly for the air-conditioned office buildings. The adaptation potential of various building designs is also evaluated. Based on the descriptive statistics method, the Pearson Product Moment Correlation and the regression analysis method, ten years of historical hourly climatic data for Australia are first analyzed. The distribution patterns of key weather parameters between a Test Reference Year (TRY) and multiple years (MYs), and between relatively cold and hot years are also compared. The possible cross-correlation between several different weather variables are then assessed and established. These findings form a useful basis and provide insights for the development of future weather models under "hot" global warming conditions and the explanation of building performance at different locations. Based on a review of the existing weather data generation models and findings from historic climatic data analysis, an effective method to generate approximate future hourly weather data suitable for the study of the impact of global warming is presented. This is achieved by imposing the future temperature projection from the global climate model on top of the historically observed weather data. Depending on the level of information available for the prediction of future weather conditions, this method allows either the method of retaining to current level, constant offset method or diurnal modelling method to be used. Therefore it represents a more comprehensive and holistic approach than previous one that have been used to convert the available weather data and climatic information to a format suitable for building simulation study. An example of the application of this method to the different global warming scenarios in Australia is also presented. The performance of a representative office building is then examined in details under the five weather scenarios (present, 2030 Low, 2030 High, 2070 Low and 2070 High) and over all eight capital cities in Australia. The sample building used for this study is an air conditioned, square shape, ten storey office tower with a basement carpark, which is recommended by the Australian Building Codes Board to represent the typical office building found in the central business district (CBD) of the capital cities or major regional centres in Australia. Through building computer simulations, the increased cooling loads imposed by potential global warming is quantified. The probable indoor temperature increases and overheating problems due to heat load exceeding the capacity of installed air-conditioning systems are also presented. It is shown that in terms of the whole building indoor thermal environment, existing buildings would generally be able to adapt to the increasing warming of the 2030 year Low and High scenarios projections and the 2070 year Low scenario projection. For the 2070 year High scenario, the study indicates that the existing office buildings in all capital cities will suffer from the overheating problem. To improve the building thermal comfort to an acceptable standard (ie, less than 5% of occupied hours having indoor temperature over 25°), a further increase of 4-10% of building cooling load is required. The sensitivity of different office building zoning (i.e. zone at different floors and/or with different window orientation) to the potential global warming is also investigated. It is shown that for most cities, the ground floor, and the South or Core zone would be most sensitive to the external temperature change and has the highest tendency to having the overheating problem. By linking building energy use to CO2 emissions, the possible increase of CO2 emissions due to increased building energy use is also estimated. The adaptation potential of different designs of building physical properties to global warming is then examined and compared. The parametric factors studied include the building insulation levels, window to wall ratio, window glass types, and internal load density. It is found that overall, an office building with a lower insulation level, smaller window to wall ratio and/or a glass type with lower shading coefficient, and lower internal load density will have the effect of lowering building cooling load and total energy use, and therefore have a better potential to adapt to the warming external climate. This phenomenon can be linked to the nature of internal-load dominated office-building characteristics. Based on these findings, a series of design and adaptation strategies have been proposed and evaluated.

Thesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 83-88).
Society's dependence on fossil fuels, spawned during the industrial revolution of the 19th century, increased the physical isolation between the sites of energy consumption, and sites of energy production. Rapid population growth and urbanization following this period gave rise, in the 20 th century, to concerns around the impact of humans on the environment. These concerns precipitated an increased focus on renewable energy, and sustainable development models present in contemporary urban planning discourse. Despite the increased focus on urban sustainability, the rapid expansion of renewable energy capacity and supporting policies, municipal governments in the United States continue to struggle with incorporating renewable energy systems into the built environment. The primary challenges concerning this integration rest in the capacity of municipal government to reinterpret the built environment as a framework for renewable energy, to conduct spatial analysis of the potential capacity in the built environment, and to synthesize that analysis with municipal policies in order to develop more robust and specific targets for renewable energy development. In response to these challenges, I assess opportunities and barriers for renewable energy development in the built environment, and synthesize established methods of spatial analysis, renewable energy policy, and project development models, to inform the role of municipal government in future planning efforts around renewable energy. To investigate the potential practical applications of this research, I focus on the city of Burlington, Vermont, which in 2014, earned the status as the first city in the United States to source 100% of its electricity from renewable sources. I question the replicability of the means by which Burlington attained this status, whether further opportunities exist for Burlington to expand its support for renewable energy, and what role the municipal government might assume in this expansion. I find the means by which Burlington sources its renewable energy only partially replicable, but I also find significant opportunities for Burlington to expand support for renewable energy within its municipal boundaries. I conclude my research by providing my findings to the city, in hopes that they will strengthen the role of municipal government in renewable energy planning.
by Ethan Lay-Sleeper.
M.C.P.

Global concern about climate change and its impacts on the environment isprogressively increasing. This has raised an important issue in the buildings andconstruction industry regarding the effects of climate change on the buildingenergy performance. Currently, many residential buildings do not fulfill theenergy requirements even with the current weather conditions, mainly becauseof poor design or because the buildings are designed according to olderregulations. Consequently, there is a need for significant changes in the buildingdesign and construction in order to create a more sustainable built environmentwith lower energy consumption. However, it is not possible to change all thesebuildings in order to meet the needs of today. It is therefore of utmostimportance that the energy production comes from renewable sources as ameans to mitigate the potential environmental impacts of climate change.In Sweden, the field of renewable energy has seen a significant growth inrecent years, and particularly in Gotland, where the project under investigationis located. In Gotland, several wind farms and wind turbines have already beeninstalled in order to benefit from the advantageous wind conditions of the island.However, the development of the project for improving the connection ofGotland’s electricity grid with the Swedish mainland power grid has come intoa halt since 2017, and Gotland is now facing major issues in terms of electricityconsumption. And as climate change only escalates in the future, it is crucial toaddress this issue. Through an extensive study of the residential sector ofGotland, this thesis examines the buildings’ energy performance with theintention of finding and proposing possible solutions and alternatives that caneventually flatten the peaks in the energy consumption of the built environmentin Gotland.

With the advent of real-time high bandwidth multimedia services, enhancing quality of service (QoS) in communication networks has been the prime focus of researchers. With environmental awareness becoming a global concern, the need to have energy efficiency in communication networks has intensified. Moreover, as the network size and the number of users increase, the introduction of energy efficient networks has become essential. Very little work has been carried out so far in vehicular communication networks for energy efficiency, even though their size and the number of users is equivalent to that of the cellular network. Provisioning multimedia services in vehicular networks is challenging due to the dynamic nature of the environment in which they operate. Analysing the performance of such systems from both QoS and energy perspectives redefines the problem. Therefore, there is a need to introduce systems which not only maintain QoS in these environments, but also save significant amounts of energy. Vehicular networks comprise intelligent vehicles fitted with an on-board unit (OBU) with wireless communication, sensing, and computing capabilities, in addition to fixed resources. Vehicular communication will play a key role in providing safety, security, and entertainment for drivers, passengers, and pedestrians in futuristic “smart cities.” This thesis studies the performance of city vehicular communication systems in terms of QoS and energy consumption. Initially, a city vehicular mobility simulator based on a 3×3 km2 Manhattan grid is developed which includes important traffic characteristics in a typical city such as vehicular flow and speed. Next, a vehicular ad hoc network (VANET) comprising three routing protocols, namely multihop (MH) routing, position based routing with most forward within radius (PRMFR), and position based routing with nearest forward progress (PRNFP), is developed in this environment. The performance of the aforementioned routing protocols is evaluated in terms of QoS. Additionally, two energy efficient routing protocols are proposed, namely single cluster-head (SCH) and double cluster-head (DCH) based routing. The performance of the SCH and DCH routing protocols from both QoS and energy perspectives is evaluated and compared with that of the MH routing, store-carry and forward (SCF) routing, and two pure vehicle-to-roadside (V2R) routing approaches. Moreover, an energy efficient content distribution network (CDN) for this environment is proposed. A mixed integer linear programming (MILP) model that optimises the number and locations of Wi-Fi enabled caching points (CPs) and cellular basestations (BSs) is developed, with the objective of minimising the total network power consumption while serving the total traffic at each hour of the day. The performance of the proposed energy efficient CDN under different scenarios and different power management mechanisms in terms of both QoS and power efficiency is evaluated. Since there is no mechanism in the MILP model to switch a CP, once installed, into low power state, an analytical queuing model is developed for the CP, where the CP sleeps (takes vacations) during its inactivity periods to save energy while maintaining the required QoS.

This research aims at exploring meanings, qualities and analytical abilities of density concept and its potential interpretations in architecture and sustainability fields. Despite the growing unsustainability of today's city facing an effective energy and environmental crisis, recent statistics have confirmed the increasing attractive power of metropolitan areas. Within the context of European compact city, new building models based on energy conservation principles account for an insignificant percentage compared to the great mass of existing city whose functioning remarkably affects the inefficiency of the whole metropolitan system. Therefore an approach determining design instruments and methods at urban and architectural scale must be found in order to set out conditions more appropriate to the compact city. At this analysis stage, the relationship between energy and form takes a central role in the variation of energy performances; at the same time the concept of density has showed the ability to describe the morphological performances of the built form. The general aim of the present research is to determine the relationships among built-form, energy and urban fabrics by the density parameter in compact city with Mediterranean climate. This research is composed by four interconnected parts. The first one examines the relationship among current urban and energy dynamics to comprehend the role and contribution of the building industry in the light of the scientific progress and the implementation of present operational and regulatory instruments. The second one investigates role and evolution of the density concept as parameter, design instrument and basis of theoretical categories, especially referring to interactions with urban form and sustainability. In the third part the analytical and interpretative abilities of density are employed in order to prove the environmental implications and verify the existence of interactions among urban sustainability indicators and density. Finally, the fourth part enquires into the relationships among form, building, density and energy set up in the compact fabrics in Rome and Barcelona by models and simulations in order to control the main formal, building and energy factors parametrically. The influence of urban morphology, built-form and constructive features on solar access and energy demand for conditioning are shown by different density indicators that are the more suitable to express reliable trends. Firstly results point out that the contribution of the built environment to the complex energy issue arisen by metropolitan systems must be focused on the reduction of the demand - even before on the consumption and impact - operating with multi-scale instruments and methods for the transformation of existing city. The density has a preferred role in the relationship between sustainability and form thanks to its interpretative skills and meanings undertaken as theoretical and design category. At the metropolitan scale, urban quality indicators and density do not always show evident relationships with energy and environmental implications. Built-form typology and constructive features are the main factors that occur on energy performances variation of urban fabrics. The investigation of these kind of performances by density parameters leads to the comprehension of the different energy behavior in each urban texture, offering a contribution to the energy analysis at urban scale. Methodology and the defined parameters of density show themselves as knowledge base for aware transformations of Mediterranean compact city as well as applications in other urban contexts both for existing and new constructions.
La ricerca esplora significati, proprietà e capacità analitiche del concetto di densità e delle sue possibili interpretazioni nell’ambito dell’architettura e della sostenibilità. Il suo obiettivo è la determinazione di relazioni tra costruito, energia e forma dei tessuti urbani della città compatta mediterranea ricorrendo alla densità quale parametro utile a decifrarne le specificità. A dispetto della sempre maggiore insostenibilità della città odierna, di fronte alla crisi energetica ed ambientale in atto, recenti statistiche hanno confermato il crescente potere attrattivo delle aree metropolitane. Nel contesto della città compatta europea, i nuovi modelli insediativi basati su principi di risparmio energetico rappresentano una percentuale insignificante rispetto alla città esistente che, nel funzionare, incide notevolmente sull’inefficienza dell’intero sistema metropolitano. In questo quadro, potrebbe essere risolutivo identificare un approccio che individui strumenti e metodi progettuali alla scala urbana piuttosto che a quella architettonica, utili a definire condizioni più appropriate e realmente incisivi per la città compatta. Se riferito in primo luogo a tale scala il rapporto tra energia e forma assume un ruolo centrale sulla variazione delle prestazioni energetiche; allo stesso tempo il concetto di densità appare un’efficace strumento di analisi delle prestazioni morfologiche del costruito. La ricerca si compone di cinque parti. La prima analizza la condizione odierna delle dinamiche urbane ed energetiche, per comprendere ruolo e contributo dell’edilizia alla luce dell’avanzamento del pensiero scientifico e degli strumenti operativi disponibili. La seconda affronta il significato e l’evoluzione del concetto di densità quale parametro di misura, strumento progettuale e fondamento teorico, facendo riferimento in particolare alle interazioni con la forma urbana e la sostenibilità. Nella terza si utilizzano le capacità analitiche della densità per comprovare le implicazioni ambientali e verificare l’esistenza di leggi di dipendenza tra indicatori di sostenibilità urbana e densità. La quarta pone le basi per la comprensione delle relazioni tra densità ed energia alla scala urbana. La quinta parte, infine, indaga tali relazioni nei tessuti compatti di Roma e Barcellona declinandole in termini di caratteri formali e costruttivi, con l’ausilio di modellazioni e simulazioni strutturate allo scopo di controllare i corrispondenti fattori. S’illustra l’influenza di morfologia urbana e caratteri tipologico-costruttivi su guadagno solare e domanda energetica per riscaldamento e climatizzazione, individuando per mezzo di differenti definizioni d’indicatori di densità, i più adeguati ad esprimere con queste leggi di variazione affidabili. I risultati evidenziano che il contributo dell’edilizia alla complessa questione energetica posta dai sistemi metropolitani deve concentrarsi sulla riduzione della domanda - ancor prima che su consumo e impatto - operando con strumenti e metodi interscalari per la trasformazione della città esistente. La densità ha un ruolo privilegiato nel rapporto forma-sostenibilità per capacità interpretative e significati assunti quale categoria teorica e progettuale. A scala metropolitana, indicatori di sostenibilità urbana e densità non sempre mostrano chiare relazioni con le implicazioni ambientali ed energetiche. Morfologia, tipologia e aspetti costruttivi sono i fattori che più intervengono sulla variazione delle prestazioni energetiche dei tessuti urbani. Analizzarli mediante parametri di densità conduce alla comprensione del diverso comportamento energetico, fornendo un contributo agli strumenti d’indagine a scala urbana e favorendo una connotazione più efficiente del costruito riconducibile alla dimensione della densità sostenibile. Il metodo e gli strumenti individuati si offrono come base di conoscenza per trasformazioni consapevoli della città compatta mediterranea
El presente estudio indaga significados, propiedad y capacidad analíticas del concepto de densidad y de su posible interpretación en el ámbito de la arquitectura y de la sostenibilidad. El principal objetivo es determinar las relaciones entre ambiente construido, energía y forma de los tejidos urbanos recurriendo a la densidad como parámetro útil para descifrar sus especificidades de la ciudad compacta mediterránea. A pesar de una siempre mayor insostenibilidad de la ciudad actual, frente a la crisis energética y ambiental en curso, estadísticas recientes han confirmado el creciente poder atractivo de las metrópolis. En el contexto de la ciudad europea, los modelos de asentamiento actuales, basados en principios de ahorro energético, constituyen un porcentaje insignificante frente a la ciudad existente que, funcionando, grava notablemente en consumo el sistema metropolitano. En esta situación, podría ser resolutivo identificar un acercamiento que identifique herramientas y métodos para el proyecto a escala urbana, que sean útiles para definir condiciones más apropiadas y sean realmente eficaces para la ciudad compacta. Si se refiere en primer lugar a dicha escala, la relación entre energía y forma asume una función central para la variabilidad de la prestación energética; al mismo tiempo el concepto de densidad parece una herramienta eficaz para analizar las prestaciones morfológicas del ambiente construido. La investigación se compone de cinco partes. La primera analiza las dinámicas urbanas y energéticas actuales, para entender capacidad y contribución de la construcción a la luz del avance del pensamiento científico y de las herramientas disponibles. La segunda trata el significado y la evolución del concepto de densidad como parámetro de medida, herramienta del proyecto y origen teórico de la arquitectura, con particular referencia a las interacciones con la forma urbana y la sostenibilidad. En la tercera se utilizan las capacidades analíticas de la densidad para comprobar las repercusiones ambientales y verificar la existencia de leyes de dependencia entre indicadores de sostenibilidad urbana y densidad. La cuarta explica las relaciones entre densidad y energía a la escala urbana. La quinta, finalmente, estudia estas relaciones en los tejidos compactos de Roma y Barcelona, explicándolas en función de forma i construcción, con el auxilio de modelos y simulaciones. Se muestra la influencia de la morfología urbana y las características tipológicas y constructivas sobre la captación solar y la demanda energética por calefacción y climatización, individualizando entre diferentes indicadores de densidad los más apropiados para representar tendencias fiables. Los resultados prueban que la contribución de la construcción a la compleja cuestión energética tiene que basarse en la reducción de la demanda - antes que del consumo y del impacto - utilizando herramientas y métodos multi-escalares para la transformación de la ciudad existente. La densidad tiene una función privilegiada en la relación forma-sostenibilidad que depende de sus capacidades analíticas y significados en calidad de categoría teórica y del proyecto. A escala metropolitana, los indicadores de sostenibilidad urbana y densidad no siempre muestran una relación clara con las repercusiones ambientales y energéticas. Morfología, tipología y aspectos constructivos son los factores que más influyen sobre la variación de la prestación energética de los tejidos urbanos. Analizarlos recurriendo a parámetros de densidad, lleva a entender el diferente comportamiento energético, contribuye a las investigaciones a escala urbana y favorece la eficiencia del ambiente construido, con lo cual se reconduce el análisis al concepto de densidad sostenible. La metodología y las herramientas individualizadas se ofrecen como base de conocimiento para orientar las transformaciones de la ciudad compacta mediterránea.

This research addresses the dual challenge faced by Burkina Faso engineers to design sustainable low-energy cost public buildings and domestic dwellings while still providing the required thermal comfort under warmer temperature conditions caused by climate change. Past and potential climate induced future energy demand for air conditioning has been investigated. It was found based on climate change SRES scenario A2 that predicted mean temperature in Burkina Faso will increase by 2°C between 2010 and 2050. Therefore, in order to maintain a thermally comfortable 25°C inside public buildings, the projected annual energy consumption for cooling load will increase by 15%, 36% and 100% respectively for the period between 2020 to 2039, 2040 to 2059 and 2070 to 2089 when compared to the control case. It has also been found that a 1% increase in population growth will result in a 1.38% and 2.03% increase in carbon emission from primary energy consumption and future electricity consumption respectively. Furthermore, this research has investigated possible solutions for adaptation to the severe climate change and population growth impact on energy demand in Burkina Faso. It has been found that shading devices could potentially reduce the cooling load by up to 40%. Computer simulation programming of building energy consumption and a field study has shown that adobe houses have the potential of significantly reducing energy demand for cooling and offer a formidable method for climate change adaptation. Finally this research has shown, based on the Net Present Cost that hybrid photovoltaic (PV) and Diesel generator energy production configuration is the most cost effective local electricity supply system, for areas without electricity at present, with a payback time of 8 years when compared to the business as usual diesel generator stand-alone configuration. It is therefore a viable solution to increase electricity access to the majority of the population.

The motivation for development of energy efficiency and implementation of novel advanced materials applied in buildings can be traced to increasing energy costs in conjunction with an enhanced environmental awareness among people. This doctoral dissertation presents contributions towards sustainable building, where factors such as building technology, energy efficiency in buildings, workers' health issues during construction measures, and certain economic considerations for renovation of buildings have been considered. The research study aims to provide a knowledge base for motivating building owners to renovate buildings based on energy efficiency and improved indoor environment. The initial phase of the research study identifies a detailed description of common drivers, expected in renovation projects by building owners. In the second phase, an information base is identified which may facilitate the bidding processes for decision makers by means of technological, social and economic aspects. The aforementioned information base can also contribute to attentive decisions regarding sustainable renovation and energy saving measures. A strategy was developed within the Renovation Workshop of Riksbyggen, in order to promote energy saving measures concurrent with major renovations in residential buildings. This operational decision support process was applied in a tenant owners' cooperative in Sweden. The objective of this process was to showcase and more importantly to implement energy saving measures, based on knowledge transfer between different parties involved in the renovation project. For the conducted case study, this process was shown to be of great importance when decisions regarding energy saving measures in conjunction with scheduled renovations are being planned. A unique case study was conducted on two of the most commonly used environmental certification programs for buildings in Sweden; Environmental Building (Miljöbyggnad) and GreenBuilding. Following a granted access to a limited database of submitted applications to Sweden Green Building Council, the most common mistakes in these were identified and categorized. This study contributed to further understanding about the level of ability among building consultants, comprehension of environmental certification, and enhancement of the ability to produce high-quality calculations concerning building-related energy usage. In addition, this insight can provide a basis for planning of continuing education of consultants within the field of building technology. For a church building, a study was conducted subsequent to an exchange of an existing electric coil heating system to a hydronic ground source heat pump system. Analyses of the energy demand and energy signature, prior to and after installation were carried out. The replacement of the original heating system with a ground source heat pump system for the church building constitutes a reduced energy consumption level of approximately 66%, at the average outside temperature of -2.30 °C. This study demonstrated that data from a detailed electric bill can be utilized in order to obtain the energy signature of the building and henceforth assess the energy savings. One aspect of the research, examined the decision making process related to sustainable renovation and refurbishment in buildings. The utilized methodology identified three distinct phases in order to instigate an engagement in sustainable renovation, by means of questionnaires and semi-structured interviews. In particular, the attitudes of stakeholders in Sweden, Denmark and Cyprus to sustainable building were studied through three separate case studies. Within the framework of this study, it was identified that building physics and durability are among the most important drivers for energy renovation. The results provided an insight into the renovation process in the aforementioned countries and identified that drivers such as improvement of indoor air quality and elimination of moisture in the building envelope are also of crucial importance. Another aspect of the conducted research highlights workplace accidents occurring within the Swedish construction sector. The purpose of this study was to serve as a useful tool to track the working environments of construction workers in order to reduce health and safety issues within the construction sector. The findings of this research suggest that despite laws, regulations or additional factors that seek to ensure a safe and healthy environment for construction workers, the Swedish construction work force still faces challenges. Moreover, it is identified that construction workers participating in the study call for additional measures to ensure occupational health and safety. Improved knowledge of economic performance and technical results of renovations can contribute to a snowball effect, with more property owners recognizing the value of energy aspects and thus provide an increased level of energy savings.

QC 20140127

A Concept for promotion of sustainable retrofitting and renovation in Early Stages (ACES)

This paper intends to offer insights into the internationally recognized LEED Green Building Rating System by taking a closer look at the short-­ and long-­term upsides and downsides of the system in a Finnish construction project, case Lintulahti. This qualitative research has been based on a research model and the primary data has been collected by conducting interviews with industry professionals involved in the project. A great deal of academic literature claims that the benefits of green building exceed its costs. The empirical findings in this paper imply that this claim is valid even for the case study and that LEED can be applied in a Finnish project. However, several challenges related to the implementation exist.

Environmental problems such as climate change resulting from greenhouse gas emissions present alarming challenge to carbon intensive energy systems. In response, the European Union at the regional level and the United Kingdom at the national level responded to this development by formulating and implementing proactive low carbon transition policies over the past few decades. Using recent transition theories, this thesis provides explorative analysis of low carbon transition pathways that have taken place and that are likely to take place, in the UK road transport and electricity generation sectors. Using reliable data and information, this research applied the concepts of transition pathway theory (the multi-level and multi-phase perspectives) in the context of energy system (as a socio-technical system) to analyse low carbon energy transition prospects in the two case study sectors. Findings indicate that transition in the road transport sector is currently at the take-off phase of transformation pathway to biofuel blends, hybrid electric vehicles, as well as niche technologies such as battery electric vehicles. For the emergence of an ideal low carbon road system in the UK, it is shown that the transformation pathway is insufficient and the likely pathway sequence to full decarbonisation will be transformation-substitution-de-alignment/re-alignment. On the other hand, the fossil fuel electricity generation sector is currently at the take-off phase of substitution pathway to renewable electricity. For the emergence of a single power generation technology, the result shows that the most likely scenario is the de-alignment/re-alignment pathway. Under this pathway, the power industry will be characterised by loosely coupled grid islands located close to consumers, necessitating bidirectional flows of electricity to balance demand and supply. At the national level, the transition assessment indicates that the overall carbon performance of the UK energy system is successful and is in agreement with the targets set in the Kyoto Protocol.

The sound field in rooms of small dimensions used for music reproduction is characteristically different from that found in larger rooms for music performance such as auditoria. Key differences between small critical listening spaces and large auditoria are the vastly different ranges of energy decay, 100 ms for the former and up to 8 s for the latter, and its directional behaviour, typically non-diffuse for the former and approximating a diffuse field for the latter. Despite these substantial differences, most of the metrics developed to describe the sound field in large spaces are evoked to quantify the performance of small rooms. This project focuses on developing measurement methods to characterise temporal and spatial qualities of sound in small rooms. A number of methods based on currently available acoustic probes have been developed. The implementation requisites and accuracy for each method has been quantified. Factors such as direction, time of arrival and strength of reflections have been extracted using signal analysis techniques based on the active instantaneous intensity and short-time Fourier transform. These factors are subsequently mapped to allow a description of their evolution through the energy decay in the room for a given measurement location. The best performing system, based on the use of one-dimensional p-p intensity probe mounted in a custom cradle, achieves a minimum overall mean error of 0.226 degrees and 2.971 degrees for the direct sound and first reflection respectively, which is near or below the measured human minimum audible angle (MAA). The method developed has direct applications in the quantification of small room acoustic sound fields for critical listening purposes.

Cloud computing enables the delivery of remote computing, software and storage services through web browsers following pay-as-you-go model. In addition to successful commercial applications, many research efforts including DOE Magellan Cloud project focus on discovering the opportunities and challenges arising from the computing and data-intensive scientific applications that are not well addressed by the current supercomputers, Linux clusters and Grid technologies. The elastic resource provision, noninterfering resource sharing and flexible customized configuration provided by the Cloud infrastructure has shed light on efficient execution of many scientific applications modeled as Directed Acyclic Graph (DAG) structured workflows to enforce the intricate dependency among a large number of different processing tasks. Meanwhile, the Cloud environment poses various challenges. Cloud providers and Cloud users pursue different goals. Providers aim to maximize profit by achieving higher resource utilization and users want to minimize expenses while meeting their performance requirements. Moreover, due to the expanding Cloud services and emerging newer technologies, the ever-increasing heterogeneity of the Cloud environment complicates the challenges for both parties. In this thesis, we address the workflow scheduling problem from different applications and various objectives. For batch applications, due to the increasing deployment of many data centers and computer servers around the globe escalated by the higher electricity price, the energy cost on running the computing, communication and cooling together with the amount of CO2 emissions have skyrocketed. In order to maintain sustainable Cloud computing facing with ever-increasing problem complexity and big data size in the next decades, we design and develop energy-aware scientific workflow scheduling algorithm to minimize energy consumption and CO2 emission while still satisfying certain Quality of Service (QoS) such as response time specified in Service Level Agreement (SLA). Furthermore, the underlying Cloud hardware/Virtual Machine (VM) resource availability is time-dependent because of the dual operation modes namely on-demand and reservation instances at various Cloud data centers. We also apply techniques such as Dynamic Voltage and Frequency Scaling (DVFS) and DNS scheme to further reduce energy consumption within acceptable performance bounds. Our multiple-step resource provision and allocation algorithm achieves the response time requirement in the step of forward task scheduling and minimizes the VM overhead for reduced energy consumption and higher resource utilization rate in the backward task scheduling step. We also evaluate the candidacy of multiple data centers from the energy and performance efficiency perspectives as different data centers have various energy and cost related parameters. For streaming applications, we formulate scheduling problems with two different objectives, namely one is to maximize the throughput under a budget constraint while another is to minimize execution cost under a minimum throughput constraint. Two different algorithms named as Budget constrained RATE (B-RATE) and Budget constrained SWAP (B-SWAP) are designed under the first objective; Another two algorithms, namely Throughput constrained RATE (TP-RATE) and Throughput constrained SWAP (TP-SWAP) are developed under the second objective.

Information technology plays an increasingly important part in representing, managing, and driving the field of sustainable energy. However, current paradigms for representing much of this information can be fragmented, singular, and extremely domain focused. Linkage with wider concepts, for example between energy supply and demand data, can be minimal. This dissertation investigates ways in which such data linkages can be expanded upon, applying the latest concepts of Semantic Web technology to the area. This dissertation examines the role of the Semantic Web in representing information relevant to sustainable energy, with a particular focus on energy policy, energy supply, and the demands of the built environment. An approach for representing such information is outlined in the dissertation, which introduces new ontologies for representing energy policy and building information data and methodologies for modelling such data. Existing ontologies for representing energy supply are discussed, as are common connections between these areas and a server platform for knowledge storage and presentation. Additionally, some focus is directed towards the usability and accessibility of such data and the implementation of proof of concept applications targeted at specific areas within sustainable energy are presented. Using the outlined approach, energy information can be interlinked to allow multilevel data navigation from international policy data, through energy infrastructure, to individual energy demands, and ultimately to extremely detailed building component levels of granularity. Such data can be interlinked into wider linked data initiatives, increasing usefulness and expanding the scope for increased analysis. The implications of the outlined approach are discussed and evaluated with regard to various identified use cases requiring different levels of data granularity, in addition to impact on the wider domain of information management. This dissertation demonstrates, at a proof of concept level, that Semantic Web technology can be of significant benefit across the domain of sustainable energy.

Though mandatory to be pursued, improved energy efficiency is not the only target to reach. The quality of energy has to be assessed as well. Most of the overall energy use in residential building is for low temperature heat, i.e. temperatures relatively close to the outdoor conditions. From a thermodynamic point of view, this is a degraded form of energy with low potential to be converted into work. On the other hand energy demand is mostly met with high quality energy, such as electricity and natural gas. There is a mismatch between supply and demand, which is not clearly shown by the sole energy analysis. Target of this thesis is to analyze the energy use in buildings from the point of view of its quality, to provide effective theoretical and calculation tools to investigate this mismatch, to assess its magnitudo and to propose improvements aiming at a more rational use of the energy. The idea behind the quality is clarified with the concept of exergy.

The potential for improvement in space heating is shown. In no heating system the overall exergy efficiency is above 20%, with fossil fuels. Using direct electricity heating results in exergy efficiency below 7%. Most of the household appliances processes have low-exergy factors but still are supplied with electricity. This results in poor exergy efficiencies and large exergy losses.

Systems are poorly performing because little consideration is explicitly given to energy quality. Policies to lower the energy demand, though vital as first step towards an improved use of energy, should not neglect the exergy content.

The problem is then shifted to find suitable supplies. Electricity can be exploited with low exergy losses with high-COP heat pumps. Use of fossil fuels for heating purposes should be avoided. District heating from cogeneration and geothermal proves to be a suitable solution at the building level. The issues connected to its exploitation forces to shift the boundary layers of the analysis from the building level to the community level. A rational use of energy should address the community level. The system boundaries have to be enlarged to a dimension where both the energy conversion and use take place with reduced energy transportation losses. This is a cost-effective way to avoid the waste of the exergy potential of the sources with exergy cascade and to make it possible the integration of with renewable sources. Exergy efficiency of the buildings is a prerequisite for a better of energy in this field.

IEA ECBCS Annex 49: Low Exergy Systems for High Performance Buildings and Communities
ESF Cost C24: Analysis and Design of Innovative Systems for Low-EXergy in the Built Environment: COSTeXergy

Domestic energy consumption has increasingly become a cause for concern for governments, energy suppliers, and individual householders. Issues surrounding gas and electricity used in the home relate to the increasing cost of fuel, the rise in the incidence of fuel poverty, carbon dioxide emissions from fossil fuels contributing to climate change, security of supply due to geo-political disagreement and the age and condition of the existing energy infrastructure. While buildings and appliances have become more energy-efficient, usually driven by legislation, the energy-consuming behaviour of individuals is very difficult to change. Domestic energy monitoring has so far only been carried out at a household level, while the behaviour of individuals within households has remained ambiguous. There is a gap in current knowledge about how people use energy at home, mainly because it is very difficult to capture everyday behaviour without influencing the behaviour being observed. Initiatives and campaigns targeting domestic energy-consuming behaviour have been based on assumptions of how people use energy in their homes, and have been found to be ineffective. There is a need for an unobtrusive method of capturing domestic energy behaviour. This research presents a technique to deliver this requirement by enabling the tracking of people in their homes with a small number of cost-effective RFID (Radio Frequency ID) devices. Using this technique the location of multiple individuals wearing RFID tags can be determined, thereby creating an unobtrusive RTLS (Real Time Location System). This technique has been extensively evaluated through a series of tests within a typical 1940’s semi-detached house in North West England, and has been found to be able to successfully locate individuals to room level. If this RTLS data is matched with appliance level energy data, energy-consumption can be attributed to the individuals responsible, and personalised everyday energy-consuming behaviour can be established.

With an increasing awareness of energy consumption and CO 2emission in the population, several initiatives to reduce CO2emissions have been presented all around the world. The main part of these initiatives is a reduction of the energy consumption for existing buildings, while the others concern the building of eco-districts with low-energy infrastructures and even zero-energy infrastructures. In this idea of reducing the energy consumption and of developing new clean areas, this master thesis will deal with the high energy quality services for new urban districts. In the scope of this master thesis project, the new concept of sustainable cities and of clusters of buildings will be approached in order to clearly understand the future challenges that the world’s population is going to face during this century. Indeed, due to the current alarming environmental crisis, the need to reduce human impacts on the environment is growing more and more and is becoming inescapable. We will present a way to react to the current situation and to counteract it thanks to new clean technologies and to new analysis approaches, like the exergy concept. Through this report, we are going to analyze the concepts of sustainable cities and clusters of buildings as systems, and focus on their energy aspects in order to set indoor climate parameters and energy supply parameters to ensure high energy quality services supplies to high performance buildings. Thanks to the approach of the exergy concept, passive and active systems such as nocturnal ventilation or floor heating and cooling systems have been highlighted in order to realize the ‘energy saving’ opportunities that our close environment offers. This work will be summarized in a methodology that will present a way to optimize the energy use of all services aspects in a building and the environmental friendly characteristics of the energy resources mix, which will supply the buildings’ low energy demands.

South Africa is undergoing a sustainability transition (ST) in its energy sector as part of its broader move towards a lowcarbon future. Past studies of the nascent ST using a multi-level approach have already proven obsolete after strong resistance from the incumbent energy regime almost derailed the fledgling renewable energy (RE) industry. After initially going to ground and contracting, the industry re-emerged strongly in South Africa’s cities, mostly in the form of rooftop solar photovoltaic (PV) systems. This study applies an integrated approach utilizing the Multi-level Perspective (MLP) to trace the current ST trajectory, whilst employing the Technology Innovation Systems (TIS) framework as a focal lens, recently adapted to the follower country context, to empirically investigate system development in the solar PV TIS. A survey was conducted to assess the drivers and challenges facing consumers of solar PV technology in cities, the results indicating that the rapid growth in distributed embedded generation (EG) was sparked by recent tax incentives and not the introduction of Feed-in Tariffs (FIT) offered by city municipalities. Whilst the RE sector and solar PV market have grown through consumer demand for EG, they still face resistance from the existing energy regime, needing further development in policy and regulation in order for South Africa’s ST to support a more complex web of distributed and embedded generation, mostly underpinned by RE technologies.

This thesis includes the results of a PhD study about methods to compare Sonic Detection And Ranging (SODAR) measurements to measurements from other instruments. The study focuses on theoretical analysis, the design of a transponder system for simulating winds and the measurement of the acoustic radiation patterns of SODARs. These methods are integrated to reduce uncertainty in SODAR measurements. Through theoretical analysis it is shown that the effective measurement volume of a range gate is 15% of a cone section based on the SODAR's Full Width Half Maximum (FWHM). Models of the beam pattern are used to calculate the ratio of air passing a turbine to that measured by a SODAR over 10 minutes with values of 3-5% found at 10ms-1. The model is used to find angles where significant Sound Pressure Levels (SPLs) occur close to a SODARs baffle giving the highest chance of fixed echoes. This is converted into an orientation guide for SODAR set-up. The design of a transponder system is detailed that aims to provide a calibration test of the processing applied by a SODAR. Testing has shown that the transponder can determine the Doppler shift equation used by a SODAR although further work is needed to make the system applicable to all SODARs. It is shown that anechoic measurements of single elements are useful for improving array models. Measurements of the FWHM and acoustic tilt angle can be achieved in the field using a tilt mechanism and a Sound Level Meter (SLM) on a 10m mast. The same mechanism can be used to calculate an effective tilt angle using the Bradley technique. It is proposed that these methods are integrated to calculate error slopes for the SODAR measurement with regards to a secondary location. It is shown that the slopes could be between 0 and 5% if the methods are fully realised and a Computational Fluid Dynamics (CFD) model is incorporated.

This thesis investigates the relationship between facilities management (FM) and design on construction projects in the Middle East region. Input provided by facilities management, the party responsible for developing and maintaining a facility support services system, is found to be vital for enhancing the design’s supportive function and preventing operation problems from occurring during the occupancy phase. An extensive literature review is undertaken to study both FM and design practices, their responsibilities during a facility’s life cycle and the types of services each discipline provides. The nature of facilities management input into design is also explored. The review of literature reveals a limited integration among the facilities management and design professions, a problem mainly caused by the nature of project delivery processes that prevent external input into the design. Accordingly, the research aims of investigating integration in practice and determining the actions to be taken to improve the situation are developed. The survey method is chosen for carrying out the research, involving FM and design practitioners. Semi-structured interviews are utilised for collecting qualitative rich information on professional views and experiences. Research findings disclose the nature of the relationship between facilities managers and designers as well as the status of their current collaboration on construction projects in the Middle East. FM-related concerns occurring during the occupancy phase are identified to show the prominence of their consideration during the design stage. This research also presents the various benefits of achieving successful integration and identifies the different means which could be implemented to improve the process of integration and avoid negative consequences currently affecting facilities and their occupants.

Environmental concerns comprising pollution and global warming are among the key parameters that steer policy making actions regarding sustainability. Energy industry that comprises energy generation, distribution, and transmission phases of energy loop is at the core of these concerns and faces challenges. Due to handling capabilities, present electricity grid is not robust enough to utilize desired level of renewable energy sources due to their intermittent nature. On the other hand, emerging policies are targeting the increased utilization of renewable energy sources. In the light of environmental policies and increased stability requirements of the electricity grids, a new concept called “smart grid” emerges. Smart grids are intended to eliminate the limitations of present electricity grids such as offering increased handling capacity for renewable energy, increased interaction of the consumers with the utilities, and increased supply and demand management. It is not easy to express a solid smart grid definition as each party (energy generation, distribution, and demand side management) has its own approach in line with the desires. Due to the potential environmental benefits of smart grids, some governments engage smart grid projects to their agenda. As solid smart grid definition does not exist, there is no available solid strategy for smart grid implementations. On the other hand, it is well understood that failure in deployment of smart grids (regardless of the technology) will have undesirable impacts on growth of renewable energy generation, and failure in meeting EU carbon targets consequently. This research seeks to develop a model that seeks optimization of smart grid implementations, and it assists decision makers with deciding on the priory areas for smart grid applicability. Stated areas in this case are neighbourhoods comprising of residential buildings where considerable amount of energy is consumed. A set of criteria regarding to residential energy use and renewable energy technologies, are defined in the study. Proposed model is embedded in a GIS platform, and the main process carried out is a prioritization mechanism that comprises Analytical Hierarchy Process (AHP) and geospatial computations like clustering and regression analysis in order to evaluate the alternative neighbourhoods. Proposed model optimizes smart grid projects by ranking of alternatives in terms of smart grid applicability. Such an aid in optimizing smart grid projects has the potential to maintain progress of smart grids in a timely manner.

The paper will examine the use of eco-design tools within the Korean electronics industry, with particular reference to mobile phone design & manufacture. Economic growth in Korea has been driven by aggressively exporting products, primarily to the US & China. Industries - such as semiconductor fabrication & electronic products - have been at the forefront of this export strategy. With impending environmental legislation threatening many of Korea’s global export markets, this study represents a timely appraisal of the industry’s ability to respond. The paper goes on to consider the extent to which eco-design tools are implemented within the Korean electronics industry, & which are most appropriate in environmental and business perspective. Whilst a simple question, this demands a non-trivial set of answers, each step posing significant problems. This is conditional on both the relevant environmental protocol for each market region, & the development of a means of cross-comparing what are very different metrics of environmental damage. In resolving this, the paper adopts Eco (or Fussler’s) Compass as a graphical representation, & uses this to evaluate the impact of a range of concepts, developed using each of the identified design tools, & based on Lifecycle Analysis (LCA- environmental quantitative evaluations method). The paper concludes by presenting cross comparing in environmental effectiveness against business and major international environmental legislations, ranking each of the tools against eco-benefit, relevance to a particular region/market & cost to the organisation, the latter being measured in times of: current capability; required investment in process; requisite developments in technology (R&D investment &/or licensing); & anticipated problems in cultural adaptation.

Renewable energies are a critical element for reducing greenhouse gases emissions and achieving a sustainable development. Until recently, building integration of renewable sources was focused on solar technologies. Nevertheless,building integrated wind turbines can and must be part of the solution to the global energy challenge. This research investigated the potential of integrating small vertical wind turbines between medium-rise buildings. Wind velocities were measured around 7 fifteenstorey towers. The measurements were carried out for nine different configurations,using a boundary layer wind tunnel and computational fluid dynamics (CFD) simulations. Computed and measured results showed reasonable agreement. The differences were more apparent at ground level. It was established that building orientation and the separation between buildings defines to a great extent the wind environment around buildings. It was found that a distance between buildings of 15 metres and an orientation of θ=260˚ produced the higher augmentation factors. This configuration produced up to 17,812kWh in a typical Nottingham UK year, using six vertical wind turbines of 2.5kW each. Results suggested that the use of CFD as a visualisation tool is extremely useful at design stages in projects involving the integration of wind turbines. Nevertheless, the results of CFD simulations are highly dependent on the type of roughness modification applied to the wall functions, the choice of the turbulence model and the modelling of the inlet wind velocity profile. Because servicing buildings accounts for around half of the UK’s total energy consumption, the need to reduce the consumption of fossil fuels is central to good building design. That is why the architectural practice must respond professionally by delivering buildings that successfully integrate wind energy technologies, which can only be achieved if the designer actively engages with the environmental design principles and improves his understanding of building physics.

According to the Swedish Government's set targets for energy use and environmental quality imposed by the European Union, the total energy per heated unit area in residential and commercial buildings will have to be decreased by 20% in 2020 and 50% by 2050 in relation to the annual consumption of 1995. The building sector should additionally be completely independent of fossil fuels for energy usage, with the increasing sector of renewable energy continuously growing until 2020. In its current state, the number of multistory buildings and single-family houses in Sweden exceeds 4 000 000 units. In order to attain the set goals, renovation of the existing housing stock is a necessity given its current relatively slow turnover. As a result of the Swedish Million Unit Program undertaken during 1965−1974, about 750 000 apartments are currently in need of renovation in order to meet today's building standards. Simultaneously, new buildings are built with energy efficiency in mind. In this study an early stage methodology is developed for building refurbishment that takes advantage of a multi-faceted approach. The methodology comprises of multiple dimensions related to a techno-economic, environmental and building occupancy approach. The work presented herein includes a thorough literature review of decision making tools within the built environment and identifies major research efforts in sustainable refurbishment. The technical aspect of this study deals with the proper identification of high-efficient insulation materials that would serve one of the set purposes of energy efficiency when utilized within building envelopes. Further, results are shown for case studies, in which economic investments in Vacuum Insulation Panels (VIPs) and a coupled heat and moisture transport for predefined configurations of VIPs with supplementary insulation of balcony slabs and wall cross-sections are considered. The developed methodology also examines simulations of the total energy consumption utilizing a set of different insulation materials such as mineral wool and VIPs, for a number of locations in Northern and Southern Europe. The research findings of this study identify several aspects of a new developed tool for decision making, to be used in sustainable renovation and refurbishment.

QC 20120918

The heavy demands on cloud computing resources have led to a substantial growth in energy consumption of the data transferred between cloud computing parties (i.e., providers, datacentres, users, and services) and in datacentre’s services due to the increasing loads on these services. From one hand, routing and transferring large amounts of data into a datacentre located far from the user’s geographical location consume more energy than just processing and storing the same data on the cloud datacentre. On the other hand, when a cloud user submits a job (in the form of a set of functional and non-functional requirements) to a cloud service provider (aka, datacentre) via a cloud services broker; the broker becomes responsible to find the best-fit service to the user request based mainly on the user’s requirements and Quality of Service (QoS) (i.e., response time, latency). Hence, it becomes a high necessity to locate the lowest energy consumption route between the user and the designated datacentre; and the minimum possible number of most energy efficient services that satisfy the user request. In fact, finding the most energy-efficient route to the datacentre, and most energy efficient service(s) to the user are the biggest challenges of multi-cloud broker’s environment. This thesis presents and evaluates a novel multi-cloud broker solution that contains three innovative models and their associated algorithms. The first one is aimed at finding the most energy efficient route, among multiple possible routes, between the user and cloud datacentre. The second model is to find and provide the lowest possible number of most energy efficient services in order to minimise data exchange based on a bin-packing approach. The third model creates an energy-aware composition plan by integrating the most energy efficient services, in order to fulfil user requirements. The results demonstrated a favourable performance of these models in terms of selecting the most energy efficient route and reaching the least possible number of services for an optimum and energy efficient composition.

While majority is focusing on the sensors, communication and network aspects of IoT systems. This thesis investigates into energy efficient aspect of scheduling messages by the things/ objects in IoT. Things or objects are clustered into IoT subgroups where each subgroup has a message broker that delivers the messages originating from members to the ultimate receiver of sensed data Le.sink. This work proposes message scheduling algorithms which improves the overall efficiency of the IoT systems. It considers the network layer routing aspect to keep the energy depletion low to provide a more optimal solution by applying certain degree of cross-layer design methodology. It proves the effectiveness and efficiency both in terms of service response time and energy consumption via simulation results. Furthermore, as messages have different priorities, an algorithm is designed considering this aspects as well. Messages are classified into high priority (HP) and best effort (BE) by the corresponding Quality of Service (QoS) aware scheduling in each IoT subgroup to differentiate emergency messages from non-mission critical messages. An energy efficient backup nodes selection algorithm is presented if any node becomes non responsive due to some internal error or external reason. This approach finds an energy efficient optimal level of replacement nodes for IoT systems, while keeping in view energy of sensor devices and the cost of deployment of the backup nodes.

During the 21st century there has been a rapid increase in grid-connected photovoltaic (PV) capacity globally, due to falling system component prices and introduction of various economic incentives. To a large extent, PV systems are installed on buildings, which means they are widely distributed and located close to the power consumer, in contrast to conventional power plants. The intermittency of solar irradiance poses challenges to the integration of PV, which may be mitigated if properly assessing the solar resource. In this thesis, methods have been developed for solar variability and resource assessment in the built environment on both national and local level, and have been applied to grid integration studies. On national level, a method based on building statistics was developed that reproduces the hourly PV power generation in Sweden with high accuracy; correlation between simulated and real power generation for 2012 and 2013 were 0.97 and 0.99, respectively. The model was applied in scenarios of high penetration of intermittent renewable energy (IRE) in the Nordic synchronous power system, in combination with similar models for wind, wave and tidal power. A mix of the IRE resources was sought to minimise the variability in net load (i.e., load minus IRE, nuclear and thermal power). The study showed that a fully renewable Nordic power system is possible if hydropower operation is properly planned for. However, the contribution from PV power would only be 2-3% of the total power demand, due to strong diurnal and seasonal variability. On local level, a model-driven solar resource assessment method was developed based on low-resolution LiDAR (Light Detection and Ranging) data. It was shown to improve the representation of buildings, i.e., roof shape, tilt and azimuth, over raster-based methods, i.e., digital surface models (DSM), which use the same LiDAR data. Furthermore, the new method can provide time-resolved data in contrast to traditional solar maps, and can thus be used as a powerful tool when studying the integration of high penetrations of PV in the distribution grid. In conclusion, the developed methods fill important gaps in our ability to plan for a fully renewable power system.

In near future, the cellular traffic will increase rapidly with majority of the increase coming from Indoor traffic. To cope up with the ever increasing demand, more Base Stations are being deployed in limited areas, which can increase the capacity but will also be responsible for increased energy consumption. Since power is a valuable commodity today both economical and environmental wise, energy efficient deployment along with capacity improvement is crucial for both incumbent and new telecom operators. The objective of this Thesis is to evaluate Power consumption and Capacity for Indoor users, both in Homogeneous and Heterogeneous infra structure cases for the 3G WCDMA/UMTS technology. The comparison is done for Uniform and Non-Uniform Traffic Distributions. In homogeneous case, results indicate that there is a tradeoff between Area Power Consumption, APC and Area Spectral Efficiency, ASE. Large Macro Base Stations covering a limited Indoor Area use less APC but provides low ASE. Small Micro Base Stations which cover the same Indoor Area consumes little more APC then Macro BS but increases the ASE manifold. In Heterogeneous case results suggest that Heterogeneous Networks (HETNET) cases enhance the Area Throughput significantly with a small increase in Area Power Consumption. MACRO+10WLAN 1is the best HETNET case in both Uniform and Non-Uniform Traffic with up to 40% Energy savings and higher data/user compared to MACRO Only deployment. The traffic patterns, number of active users in a cell and Inter Site Distances between Base Stations strongly influence the energy saving and capacity enhancements.

Radioactive radon gas, after being released from rocks, soils and building structures, can pose a significant health threat to the building occupants. This is of particular concern in tight HVAC (Heating, Ventilating and Air-Conditioning) serviced buildings where there is re-circulating air with limited fresh air intake. A thorough survey was initiated at the Hong Kong University of Science and Technology (HKUST) in 1996 and results indicate a radon average concentration of 107 Bq/m3, which is approximately 50% of the World Health Organisation's (WHO) recommended standard (200 Bq/m3). About 10% of the measurements were in excess of this WHO limit, while 46% of the samples also showed average peak radon concentrations (264 Bq/m3) in excess of this WHO limit. To overcome these elevated indoor radon concentrations, their characteristics at HKUST was studied. Radon level was found to increase linearly as a function of the length of the HVAC shut off period, and decrease exponentially upon system resumption. Radon level predictive models were developed after a series of room chamber experiments with modification factors defined to account for the indoor sinks in an effort to enhance the accuracy and applicability of the models. Following a campus-wide energy audit, two energy efficient radon management approaches were derived from the predictive models and were subsequently integrated into the existing HKUST operations. The first was defined as an Active Radon Control Approach (ARCA), where HVAC operation schedules were modified to yield an energy saving potential of around HK$2.7 Million a year. ARCA is optimised to reduce the radon dose to the HKUST occupants following the radiation protection principle of "As Low as Reasonably Achievable (ALARA)", and with considerations of economical and operational constraints. The other was a Passive Radon Control Approach (PRCA) using Polyurethane-based (P-u) paint to cover building material surfaces to reduce the radon emission.

Ship weather routing was first developed for determining the minimum time of a voyage. However, after 90's, driven by the increasing oil price and the environmental considerations, most shipping companies have began to show more and more interest in minimising fuel consumption in a route, in the meantime, maintaining a certain time schedule which is specified in the chartering contract of a merchant vessel. This topic is the focus of this thesis. A novel three dimensional dynamic programming method (3DDP) has been developed in this research to determine the optimised ship course and its corresponding engine power for minimum fuel consumption. During the optimisation process, Kwon's method as a new empirical formula is used to calculate ship speed in different weather conditions and an IMO guideline is applied to ensure ship safety during a voyage. In addition to the 3DDP method developed, three multi-objective evolutionary algorithms (MOEAs) are also proposed to treat we ather routing as a multi-objective and constrained optimisation problem. Based on ship hydrodynamic knowledge and optimisation algorithms an Intelligent Tool for Energy Efficient and low environment impact Shipping (ITEES) has been developed. ITEES is established by using the object-oriented software development theory, consisting of several independent functional modules. The OPeNDAP as an advanced communication technique is employed by ITEES for downloading deterministic weather forecast at no cost. Case studies are given in Chapter 8 of this thesis to evaluate the performance of the 3DDP method in a comparison with other different optimisation algorithms under different weather conditions. A 54,000 DWT container ship is used as the case ship. The case studies have demonstrated that, in medium sea condition, different route optimisation methods offer the similar results that the shortest route with a constant engine power brings the lowest fuel consumption. However, the results of different route optimisation methods vary significantly in rough sea states. Optimised results are not only just for fuel saving but also, most importantly, for ensuring ship safety during a voyage. Among the optimisation algorithms evaluated by the research, the 3DDP used in ITEES is able to give a better performance for fuel saving than other methods. In addition, it has the characteristics of using straight forward theory and less parameter settings compared with MOEAs that make the ITEES programme easy and convenient for operators to use.

Wind is now established in Europe as a major 'renewable energy' resource, but its large scale exploitation is increasingly limited by environmental issues. Hence, on the way to a more sustainable development, it is desirable to seek ways to incorporate it into small scale embedded generation. As a first step, a prototype of a small scale Ducted Wind Turbine has been developed and tested, which seems to be feasible for integration into a conventional building. The wind flow around the building generates differential pressures which may cause an enhanced massflow through the turbine. This thesis is concerned with the investigation of the flow through building integrated duct configurations. Hence, pressure and wind speed measurements have been carried out on a wind tunnel model at different angles of incident wind. Different duct geometries with attached spoilers have been tested, and it was confirmed that wind speeds up to 30 % higher than in the approaching free stream are induced in the duct, in some cases tolerating an angle of incident wind up to 60°. The experimental work proceeded in parallel with Computational Fluid Dynamics modelling. Adaptive gridding of the complex full model geometry required a two dimensional approach, which was used to compare the predicted flow behaviour qualitatively. Three dimensional simulation of the flow field in the building integrated duct could be compared with experimental results. A new flow field mapping approach was initialised to form a two stage process in which conditions in the large-scale flow domain, modelled in a coarse three dimensional simulation, are used as boundary conditions for a localised simulation of the duct flow. Based on performance measurements of a free standing prototype in field trials and the experimentally determined wind speed in the duct, a power prediction model was developed. For the Scottish climate, the proposed device compares favorably with conventional small wind turbines and photovoltaics. The presented work evaluates the concept of harvesting wind energy in the built environment and provides outlines for the future design of a building integrated Ducted Wind Turbine module.

An energy transition is currently taking place in many European countries. Existing studies comparing countries’ energy transition pathways are limited in scope and lack a strong theoretical foundation. This thesis addresses the lack of theoretical framework-based approaches by applying a sectoral analysis framework, identifying the main factors facilitating or hindering the sustainable energy transition in several countries, and the significant differences between them.The research focused on four countries; the Netherlands, Denmark, Germany and the United Kingdom and was limited to the residential sector of the built environment. It included the three dominant housing types: social rental; private rental; and homeownership. Data was clustered along the four dimensions of the sectoral analysis framework, identifying: (1) actors, interactions & networks; (2) the institutional or legal framework; (3) the technological framework; and (4) market demand. The same process was repeated for each of the countries, forming a detailed overview about their chosen energy transition pathways. A number of interviews were conducted to gain further insight into country-specific factors.With respect to actors, interactions and networks, this study has found that strong ties and cooperation between ministries and departments is an important factor facilitating policy success, with departmental fragmentation or competition posing a significant barrier. In terms of the institutional framework policy stability, clear targets and long-term policy framework are all factors for policy success. Conversely, frequent changes to existing policies, non-binding goals and the absence of a long-term framework are all seen as barriers for a sustainable energy transition. Looking at the technological regime, this study found countries with active support for renewable energy technologies have a higher share of renewable energy than countries where the choice of technologies is largely market-based. Past technological choices and existing energy-infrastructure were found to influence transition pathways and can be both a positive or negative factor. Lastly, with respect to market demand, the existence of a standardised housing stock was found to be a potentially significant factor for the upscaling of innovative initiatives. The existence of a large and fragmented (private) rental sector and high interest rates on financing products were found to be further barriers for the energy transition in the residential sector.This thesis has identified obstacles matching those in previous studies and introduced a number of factors facilitating policy success. It has made a first step in overcoming the lack in theoretical framework-based approaches in energy transition analysis future studies can build on.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 88-89).
Preservation of buildings is an important process for both cultural and environmental sustainability. Buildings are frequently demolished and rebuilt long before necessitated by structural or material deterioration, wasting both materials and energy. Preservation can be seen as the ultimate form of recycling; it allows existing buildings to be updated and retrofitted for continued use, optimizing the longevity of the structure while protecting its cultural significance. Currently, there is a lack of motivation and regulation for choosing preservation over new construction. The LEED guidelines give only a small number of points for building reuse, and frequently historic restrictions interfere with measures that would produce the same types of energy savings seen in new construction. This project will use several case studies, including the preservation of Pier A in New York City's Battery Park, as examples of contemporary restoration projects that have received or are anticipating LEED ratings. I will look at these projects in the context of current LEED guidelines and proposed future revisions to investigate how the LEED system addresses issues regarding preservation, and how they could be improved to encourage more sustainable renovation practices.
by Lori Ferriss.
M.Eng.

By 2050, the world’s population is expected to reach 9.7 billion, with over half living in urban settlements (United Nations, 2015). Planning and designing new urban developments and improving existing infrastructure will create or reshape urban landscapes and will carry significant implications for energy consumption, infrastructure costs, and the urban microclimate on a larger scale. Researchers and industry professionals must recognize how changes in land use affect the urban microclimate and, therefore, building energy consumption. Built environment and microclimate studies commonly involve modeling or experimenting with mass and energy exchanges between natural and the built environment. Current methods to quantify these exchanges include the isolated use of microclimate and building energy simulation tools. However, current urban planning and building design processes lack a holistic and seamless approach to quantifying all thermodynamic interactions between natural and built environments; nor is there a method for communicating and visualizing the simulated building energy data. This dissertation has developed a coupling method to quantify the effects of the urban microclimate on building energy consumption. The coupling method was tested on a medium-sized office building and applied to a design case, a redevelopment project in Pittsburgh, PA. Three distinct approaches were used. First, to develop the coupling method, a study was conducted to quantify the importance of accurate microclimate model initialization for achieving simulation results that represent measured data. This initialization study was conducted for 24 cases in the Pittsburgh climate. The initialization study developed a rule-based method for estimating the number of ENVI-met simulations needed to predict the microclimate for an annual period. Second, a coupling method was developed to quantify these microclimate effects on building energy consumption. The Center for Sustainable Landscapes (CSL) building was used as a test-case for this coupling method to measure improvement in predicting building heating and cooling energy consumption. Results show that the coupling method, more than the TMY3 weather data used for energy simulations, can improve building energy consumption predictions for the winter and summer months. Third, to demonstrate industry implications, the coupling method was applied to a design case, the Lower Hill District Redevelopment, Pittsburgh, PA. Comparing the decoupled energy model and TMY3 weather data revealed a high degree of variation in the heating and cooling energy consumption. Overall results reinforced the hypothesis that building surface level coupling is not essential if the energy model accounts for the microclimate effects. A Design Decision Support (DDS) method was also developed as a tool for project stakeholders to communicate high-fidelity simulated energy data.

With proposed increases in both freight and passenger railway in the United Kingdom and the European Union and the building of new high speed lines, there has been an increase in interest in recent years in the human response to vibration in residential environments. As with exposure to environmental noise, exposure to environmental vibration can result in adverse effects such as annoyance and sleep disturbance. However, unlike exposure to environmental noise, well established relationships to evaluate annoyance caused by vibration in residential environments do not exist. In order to predict and control annoyance caused by vibration from environmental sources, a better understanding is needed of how humans perceive vibration and how their perception relates to measureable, quantifiable features of the vibration exposure. In the work presented in this thesis, the human response to vibration is considered on both a community and individual level. The first major aim of this work is to develop statistically robust exposure-response relationships for the human response to railway and construction induced vibration in residential environments. This is achieved via a large scale field survey in which 1431 questionnaires were conducted with residents in their own homes along with extensive vibration measurements at internal and external positions. Analysis of the data collected through this field survey shows that all of the vibration exposure descriptors advocated in national and international standards are equally well correlated with annoyance due to railway induced vibration. Using a grouped regression model, exposure-response relationships describing the proportion of respondents expected to express annoyance above a given threshold are derived for railway and construction induced vibration in terms of a variety of vibration exposure descriptors. The second major aim of this work is to investigate the perception of railway induced vibration on an individual level by investigating the salient dimensions of the perception of whole body vibration. This is achieved via a subjective laboratory test in which paired comparisons of similarity and annoyance are conducted using fourteen measured railway vibration stimuli. Through multidimensional scaling analysis, it is shown that the perception of railway induced vibration is dependent on up to four perceptual dimensions. These dimensions relate to energy in the 16 Hz 1/3 octave band, energy in the 32 Hz 1/3 octave band, the duration of the train passage, and the modulation frequency of the envelope of the signal. These perceptual dimensions are related to single figure Perceived Annoyance Ratings (A) by the following relationship: $A=-0.40+4.57{{\ddot{X}}_{RMS,16Hz}}+3.18{{\ddot{X}}_{RMS,32Hz}}+0.02{{T}_{10dB}}+0.02f{}_{\bmod }$. Finally, the single figure Perceived Annoyance Ratings are related to categorical ratings of annoyance via a logistic regression model.

Purpose: There is a worldwide movement towards sustainability. A stepping-stone towards a sustainability conscience population starts in the education of the younger generation. Focusing on improving sustainability education will shift and shape youths' interests and lifestyles into an educated community that will work sustainably. A sustainability conscience community will continue to make moral sustainable decisions in their future endeavors. The gap between theory and practice of sustainability is substantial. Educational institutions must be the leaders in this subject to mold future generations’ incoming leaders into sustainability conscious critical thinkers. Current environmental issues such as climate change, CO2 Emissions, poverty and so on must impact these educational institutions to make sustainability education a priority in its curriculum. Addressing this problem requires a holistic approach which integrates sustainability education earlier on to grasp further understanding of sustainability actions in higher education and in society. Sustainability education exists in all levels. Although, sustainability education is much more prominent in higher education institutions as opposed to Elementary, Middle, and High Schools. Consequently, less students are prepared with the desired sustainability knowledge needed in higher education and students' future careers to instill in their disciplines since behavior is achieved through repetitive actions that were not set as a foundation earlier in their education. Approach: There were two approaches in this research. The first research approach was conducting a survey in 120 students, half of them in secondary education and the other half in higher education. The survey was formatted to analyze three different questions: 1) whether students in high school and higher education knew about sustainability 2) whether students' lifestyle consisted of pro-environmental actions, 3) and whether they learned to perform these actions in secondary education or higher education. The second approach was to create an educational tool to implement sustainability behavioral change strategies in their everyday lifestyles. Findings: Study found that most students are aware about sustainability. However, most students engage in pro-environmental actions in higher education because they started learning about them in higher education. Therefore, although most secondary education students are aware about sustainability, they aren't engaging in pro-environmental actions. In conclusion, a sustainability toolkit was created based on behavioral change strategies to reduce water usage, CO2 emissions, energy consumption, and waste output in their school and everyday lifestyles. Value: The efforts of sustainability in Higher Education have been clear in most recent years, although, there is still much resistance to change, transform and reimagine society and education for sustainability. The future of life and social world on Earth is in jeopardy since poverty, climate change, and lack of peace is occurring worldwide. Sustainability education must respond and act on this challenge subsequently to respect all forms of life and future generations. The mission of the sustainability toolkit is to create a pedagogy to assist educational institutions and communities to develop the skills and knowledge to work sustainably.

The growing recognition amongst local authorities of the potential of asset management to improve property management practice has led to its increased adoption. The growing trend has been supported by the development of asset management frameworks. However, evidence indicates that local authorities are failing to achieve the full benefits from their asset management implementation. The factors contributing to some of the property management problems such as reactive management, lack of leadership support, ineffective corporate landlord approach, remain. The available frameworks are incapable of mitigating the identified problems by failing to provide understanding of local authority differences. Therefore, this research aimed to develop an adaptable and flexible operational property asset management framework for local authorities in England and Scotland. The strategic management theory, review of existing literature findings and evaluation of available asset management frameworks especially the Total Asset Management Process model helped to identify, define and establish the causal logic of the asset management concepts underpinning the developed conceptual framework. Face to face semi-structured interviews followed by large scale questionnaire surveys were used to gather primary data. The key research findings are that the following are the key factors limiting asset management practice improvements in local authorities: ineffective leadership support, asset management capabilities and corporate landlord approach; inadequate asset management information systems and performance management arrangements. Principal components factor analysis was utilised to help establish underlying factors that account for flexible and adaptable asset management framework. The findings suggest that asset management processes associated with an adaptable and flexible asset management framework include a board level cross functional asset management structure; strong leadership support for both direct and indirect property; an enabling environment; an effective corporate landlord approach; an effective performance management arrangement; and availability of an appropriate management information system. The framework has been validated to be robust and can be utilised and flexibly adapted by different local authorities and provides the basis for improving the process and outcome of asset management practice.

Energy transfer is a natural phenomena that bases of the photosynthesis. In photosynthesis, chlorophyls and auxlary absorbing dyes units absorb solar energy and transfer the energy to the reaction center where other chemical reactions occur. Studies showed that energy transfer depends strongly on distance and rigidy of the structure. Rigid structures that close in space transfer energy nearly %100 efficiency. Supramolecular chemistry tries to mimic nature and miniurize natural phenomence on to molecular scale. Thus, articifial photosynthesis has been very popular in supramolecular chemistry. A lot of studies have been dedicated to diffent parts of photosynthesis. BODIPY dyes have very well defined photophysical properties that can be used in multichromic systems and designing molecular switching potential tool on in supramolecular chemistry. In this study extended BODIPY dyes constructed on a rigid xanthane scaffold have been deviced for energy transfer.