Academic literature on the topic 'Electric water heater'

Today's utilities face new challenges due to the continually increasing penetration of residential solar and other distributed, stochastic generation sources. In order to maintain balance and stability in the grid without building costly, large-scale generation plants, utilities are turning to distributed energy resources for use in demand response programs. Demand response is a cost-efficient way to balance grid load/generation without the need for increased capital investment in traditional generation resources. Demand response programs are excellent exploiters of end-user devices that otherwise further accentuate the daily load curve and thus, add to the difficulties created by daily load peaks. Electric water heaters are excellent candidates for use in demand response programs for a variety of reason. One, electric water heaters represent a large portion of daily household loads due to their high nominal power ratings (1.5 kW - 5.5kW), and frequent use estimated to account for approximately one third of all daily residential power demand. Two, they are composed of strictly resistive elements, which greatly simplifies modeling, aggregation and control. And third, they can be used for load "shedding" during periods of high electrical demand as well as load "absorbing" during periods of excess generation due to their thermal storage capabilities. With improved access and control, electric water heaters could become a major distributed energy resource for utilities. In order to properly control and use a distributed energy resource, it is important to know how these resources operate and their patterns of behavior in different environments. This thesis presents a single-element, single mass electric water heater model for analyzing the effectiveness of using electric water heaters as distributed energy resources and for participation in demand response programs. The CTA-2045 communication protocol was used for testing demand response signals. The electric water heater is modeled in Python and the communication pathway was built in C++ and Python.

In this research, the impact of solar thermal water heaters on the electric water heating load curve in a residential distribution circuit is analyzed with realistic hot water draw profiles. For this purpose, the electric and solar thermal water heater models are developed in MATLAB and validated with results from GridLAB-D and TRNSYS respectively. The solar thermal water heater model is developed for two types of collectors namely the flat plate and evacuated glass tube collector. Simulations are performed with the climate data from two cities - Madison, WI and Tampa, FL - which belong to two very different climate zones in the United States. Minute-by-minute electric energy consumptions in all three configurations of water heaters are modeled for a single water heater as well as a residential distribution circuit with 100 water heaters for daily as well as monthly time frames.<p> The research findings include:<ol><li> The electric energy saving potential of a solar thermal water heater powered by auxiliary electric element is in the range of 40-80% as compared to an all-electric water heater depending on the site conditions such as ambient temperature, sunshine and wind speed. The simulation results indicate that the energy saving potential of a solar thermal water heater is in the range of 40-70% during winter and 60-80% during summer. </li><li>Solar thermal water heaters aid in reducing the peak demand for electric water heating in a distribution feeder during sunshine hours when ambient temperatures are higher. The simulation results indicate that the peak reduction potential of solar thermal water heaters in a residential distribution feeder is in the range of 25-40% during winter and 40-60% during summer. </li><li>The evacuated glass tube collectors save an additional 7-10% electric energy compared to the flat plate collectors with one glass pane during winter and around 10-15% during summer. The additional savings result from the capability of glass tube collectors to absorb ground reflected radiation and diffuse as well as direct beam radiation for a wider range of incidence angles. Also, the evacuated glass tube structure helps in reducing wind convective losses. </li><li>From the simulations performed for Madison, WI and Tampa, FL, it is observed that Tampa, FL experiences more energy savings in winter than Madison, WI, while the energy savings are almost the same in summer. This is due to the fact that Tampa, FL has warmer winters with higher ambient temperatures and longer sunshine hours during the day compared to Madison, WI while the summer temperatures and sunshine hours are almost the same for the two cities. </li><li>As expected, the simulation results prove the fact that lowering the hot water temperature set point will result in the reduction of electricity consumption. For a temperature reduction from 120 deg. F to 110 deg. F, electric water heaters save about 25-35% electric energy whereas solar thermal water heaters save about 30-40% auxiliary electric energy for the same temperature reduction. </li><li>For the flat plate collectors, glass panes play an important role in auxiliary electric energy consumption. Flat plate collectors with two glass panes save about 10-15% auxiliary electric energy compared to those with no glass panes and about 3-5% energy saving compared to collectors with one glass pane. This is because there are reduced wind convective losses with glass panes. However, there are also transmittance losses from glass panes and there are upper limits on how many glass panes can be used.</li></ol> Results and findings from this research provide valuable insight into the benefits of solar thermal water heaters in a residential distribution feeder, which include the energy savings and peak demand reduction.<br>Master of Science

Este trabalho propõe um método com objetivo de avaliar a eficiência energética de aquecedores de água residenciais de acumulação elétricos. Os aquecedores foram submetidos a um ciclo de operação simulando uma condição de uso para o cálculo da eficiência. Este ciclo de duração de um dia é composto pelas fases: produção de água quente, reaquecimento e manutenção da temperatura interna. O método foi aplicado no programa experimental e permitiu a identificação de diversos parâmetros referentes ao funcionamento dos aquecedores, tais como: perda passiva por 24 horas, produção de água quente, tempo de reaquecimento, variação da temperatura interna da água e a sua eficiência energética.<br>This work proposes a method with objective of evaluating the energy efficiency of electrical residential storage water heaters. The heaters were submitted to an operation cycle simulating a use condition for the calculation of the efficiency. This cycle with duration of one day is composed by the phases: hot water withdrawal, temperature recovery and standby thermal loss. The method was applied in the experimental program and it allowed the identification of several parameters regarding the operation of such heaters as: standby thermal loss per 24 hours, hot water rate output, reheating time, cyclic variation of the temperature and its energy efficiency.

Alors que le secteur du bâtiment se montre de plus en plus économe en énergie, les besoins en eau chaude sanitaire (ECS) augmentent, en particulier dans les logements récents. De ce fait, il apparait nécessaire d'améliorer l'efficacité des solutions mises en œuvre pour la production d'ECS, de mieux comprendre les besoins en ECS et d'impliquer l'usager dans la prise de décision. Le projet traite du développement d'algorithmes pour le contrôle/commande « intelligent » d'installations associant chauffe-eau électrique et panneaux solaires photovoltaïques en autoconsommation. Sera mise en œuvre une stratégie fondée sur la théorie de la commande prédictive, mettant à profit les outils de l'apprentissage automatique. Cette stratégie sera généralisée aux systèmes « multi-chauffe-eau », mutualisant une production solaire photovoltaïque, parle développement d'une commande distribuée et hiérarchisée. Une expérimentation permettra d'évaluer les conditions d'acceptabilité de la solution développée et l'impact de l'information sur la prise de décision<br>While the building sector is increasingly energy efficient, the needs in domestic hot water (DHW) is increasing, especially in newer homes. Therefore, improvement of efficiency in the production of DHW, a better understanding of the needs in DHW, and user involvement in the decision-making process are necessary. The project deals with the development of algorithms for the smart control of combined electric water heaters and self-consumption photovoltaic solar panels. A model-based predictive control strategy will be developed and implemented, leveraging machine learning tools. The strategy will be generalized to multi-water heater systems, sharing photovoltaic solar production, through the development of a distributed and hierarchical control approach. An experiment will make it possible to assess the conditions of acceptability of the developed solution and the impact of information on decision-making

The main aim of my project is to develop a hardware implementation of the electronic waterheater by choosing different components and minimize the errors in the same. I have consideredseveral options depending on the availability of components, cost, reliability, implementation,financial budget, specification and thinking about the professional technical skills required. Inthis project I designed and implemented, an AVR micro controller based water temperaturemeasurement system using Atmega328p microcontroller.The idea of the project came from a company called Relek production AB, Sweden and theydevelop and supply electrical equipment for heating: such as electric boilers, under floor heatingboilers, IR heaters, emergency power plants, power monitors, etc. Now they want to develop anew version of electronic water heater and according to their specification.The microcontroller (Atmega328p) based temperature control system is used in this project forproviding better functioning of the system and will also serve the following purposes.1) As there will be less usage of energy as it is more energy efficient.2) The microcontroller along with temperature sensor decides when the heater shouldturn on/off.With this project I have designed the schematic diagram by using Eagle Autodesk PCB CADprogram. The seven-segment display is used in this project to show the current temperature. Atemperature sensor (LM35) is used in this project to sense the temperature and give thesemeasured values to the microcontroller. The temperature measurement and heater control areprocessed using C++ program.I have connected the circuit as per the schematic diagram and programed the microcontroller,interfacing all the major components like 7 segment display, temperature sensor, 2 pushbuttons(for manually incrementing and decrementing the set point in the program), and optoisolator (tosense the output from microcontroller and control the heater through thyristor).

The increased penetration of renewable energy sources poses new challenges for grid stability. The stochastic and uncontrollable generation of solar and wind power cannot be adjusted to match the load profile, and the transition away from traditional synchronous generators is reducing the grid capacity to arrest and recover from frequency disturbances. Additionally, the distributed nature of many renewable energy sources makes centralized control of generation more complicated. The traditional power system paradigm balances the supply and demand of electricity on the grid by regulating generation. As this becomes more difficult, one alternative is to adjust the load instead. This is not entirely novel, and utilities have incentivized large industrial customers to reduce consumption during peak hours for years. However, the residential sector, which constitutes 37% of electricity consumption in the U.S., currently has very little capacity for load control. Smart electric water heaters provide utilities with an appliance that can be remotely controlled and serves as a form of energy storage. They have very fast response times and make up a large amount of residential energy consumption, making them useful for load peak shifting as well as other ancillary grid services. As smart appliances become increasingly widespread, more and more devices can be brought into the utility's control network and aggregated into a flexible resource on a megawatt scale. This work demonstrates the usefulness of aggregated electric water heaters for peak shifting and frequency response. Because a large number of assets are required, emulators are developed based on observations of real devices. Emulated water heaters are then connected to an energy resource aggregator using an internet-of-things network. The aggregator successfully uses these assets to shift consumption away from peak hours. An algorithm was developed for detecting upward frequency disturbances in real-time. The aggregator uses this algorithm to show that an aggregation of water heaters is well-suited to respond to these frequency disturbances by quickly adding a large amount of load to the grid.

Distributed energy resources like residential electric water heaters and residential battery inverter systems offer a small amount of change to the grid individually. When aggregated however, these assets can cause major effects to the electric grid. Aggregating these resources allows them to take on generator-like functions with the ability to increment power and decrement power. The Western Energy Imbalance Market is an energy market offering 15 minute and 5 minute markets for energy transactions between balancing areas. Generation assets make increment and decrement bids. Traditionally the only entrants to this market have been large scale generators and large scale assets legally designated as generators. Aggregated distributed resources could offer the same increments and decrements from managing residential assets like electric water heaters and batteries. DERAS, a Distributed Energy Resource Aggregation System developed by the Portland State Power Lab group, is an aggregator of residential resources that could offer increment and decrement bids to an energy market, like an Energy Imbalance Market. This research models and simulates aggregations of distributed energy resources. This work analyzes the effects of 10,000 electric water heaters and 10,000 battery inverter systems. A simulation program was built to simulate regular use of these assets, and then add the additional effects of a decrement bid into the Western Energy Imbalance Market. The effects of the bids on energy levels inside the water heaters and batteries are examined. The power imported from the grid is also analyzed as an effect of the aggregator attempting to cover a generation decrement bid.

The Water To Air heater (WTA) is a component that heats the interior and the engine of the truck by heating coolant through a combustion of diesel fuel. It is vital that the Water To Air heater is primed with fuel prior to using it in order for it to start when desired. Priming of the heater is done in production, which is where the trucks are built. This is done to ensure that there is fuel available to heat the coolant. However, the current priming process has too many weaknesses, it is sensitive to component changes and there are a number of uncertainties present. The goal of this thesis is to investigate the priming process and try to improve the process so that it becomes more robust. The aim is to present an alternate method that could be used to minimize the number of uncertainties and the impact of these. Several methods of how to regulate the fuel supply were studied and evaluated according to a few criteria and limitations. The first method that was tested was to try and detect fuel through a simple type of Electrical Capacitance Tomography. However, initial measurements proved that it would not be possible to use this method in order to achieve the desired result. Instead, fuel was detected by creating a prototype consisting of a photoresistor and a laser pointer. Once it had been established that fuel could be detected through this prototype, a microcontroller was programmed to automatically be able to make measurements and handle the output from the photoresistor. The developed concept is a concept that, if implemented in production, would solve many of the problems that are present with the current priming process. Many of the uncertainties would either be eliminated completely, or decreased massively. However, there is some work that remains. In order to use the proposed solution as a stand-alone system that regulates the fuel supply, it is necessary that a stop signal is implemented. Additional tests need to be performed in order to decide how the final implementation is going to work. Finally, the prototype needs some improvements.<br>Extravärmaren (WTA) är en komponent som värmer både lastbilens hytt och motor genom förbränning av diesel. För att extravärmaren ska starta enligt önskemål så är det viktigt att bränsleslangarna fylls med diesel. Detta är gjort i produktion, vilket är där lastbilarna byggs, för att försäkra sig om att extravärmaren fungerar som den ska. Processen där bränsleslangarna fylls har dock allt för många svagheter, den är känslig mot ändringar av komponenter och det finns även ett antal osäkerheter närvarande. Syftet med detta examensarbete är att undersöka denna process och försöka förbättra processen så att den blir stabilare. Målet är att presentera en mer robust metod, som minimerar mängden och signifikansen av osäkerheter, för att fylla bränsleslangarna. Flera metoder för att kontrollera bränsletillförseln studerades och utvärderades utifrån ett antal kriterier och begränsningar. Den första metoden som testades var att försöka upptäcka bränsle genom att använda en enkel variant av elektrisk kapacitanstomografi. Initiala mätningar visade dock att det inte var möjligt att använda denna metod för att uppnå det önskade resultatet. Istället användes en prototyp bestående av en fotoresistor och en laserpekare för att upptäcka bränslet. När det hade fastställts att bränsle kunde upptäckas på detta sätt så programmerades en mikrokontroller för att automatiskt kunna läsa av och hantera resultatet från fotoresistorn. Det utvecklade konceptet skulle, om det implementeras i produktion, lösa många av de problem som är närvarande under den nuvarande processen. Många av osäkerheterna skulle antingen elimineras helt, eller reduceras tydligt. För att konceptet ska kunna implementeras i produktion krävs det dock framtida arbete. För att kunna använda den föreslagna lösningen som ett fristående system så krävs det att en stopsignal implementeras. Fler tester behöver utföras för att kunna avgöra hur den slutgiltiga lösningen skall fungera. Till sist så behöver prototypen vidareutvecklas.

Includes bibliographical references.<br>In our quest to use more renewable energy to reduce our dependence on non-renewable fuels man has been harnessing wind, solar and hydro energy for many years. While hydo and solar energy are well established, it is only during the last decade that serious progress in wind energy has been made. Solar energy is widely used for water or space heating while wind is used for pumping water for remote areas. This project looks into the design and development of a 6kW wind powered water heating unit.

This master thesis presents a new technological combination of two environmentally friendly sources of energy in order to provide DHW, and space heating. Solar energy is used for space heating, and DHW production using PV modules which supply direct current directly to electrical heating elements inside a water storage tank. On the other hand a GSHP system as another source of renewable energy provides heat in the water storage tank of the system in order to provide DHW and space heating. These two sources of renewable energy have been combined in this case-study in order to obtain a more efficient system, which will reduce the amount of electricity consumed by the GSHP system.The key aim of this study is to make simulations, and calculations of the amount ofelectrical energy that can be expected to be produced by a certain amount of PV modules that are already assembled on a house in Vantaa, southern Finland. This energy is then intended to be used as a complement to produce hot water in the heating system of the house beside the original GSHP system. Thus the amount of electrical energy purchased from the grid should be reduced and the compressor in the GSHP would need fewer starts which would reduce the heating cost of the GSHP system for space heating and providing hot water.The produced energy by the PV arrays in three different circuits will be charged directly to three electrical heating elements in the water storage tank of the existing system to satisfy the demand of the heating elements. The excess energy can be used to heat the water in the water storage tank to some extent which leads to a reduction of electricity consumption by the different components of the GSHP system.To increase the efficiency of the existing hybrid system, optimization of different PV configurations have been accomplished, and the results are compared. Optimization of the arrays in southern and western walls shows a DC power increase of 298 kWh/year compared with the existing PV configurations. Comparing the results from the optimization of the arrays on the western roof if the intention is to feed AC power to the components of the GSHP system shows a yearly AC power production of 1,646 kWh.This is with the consideration of no overproduction by the PV modules during the summer months. This means the optimized PV systems will be able to cover a larger part of summer demand compared with the existing system.