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Thermal energy storage in residential buildings : a study of the benefits and impactsAbedin, Joynal January 2017 (has links)
Residential space and water heating accounts for around 13% of the greenhouse gas emissions of the UK. Reducing this is essential for meeting the national emission reduction target of 80% by 2050 from the 1990 baseline. One of the strategies adopted for achieving this is focused around large scale shift towards electrical heating. This could lead to unsustainable disparity between the daily peak and off-peak electricity loads, large seasonal variation in electricity demands, and challenges of matching the short and long term supply with the demands. These challenges could impact the security and resilience of UK electricity supply, and needs to be addressed. Rechargeable Thermal Energy Storage (TES) in residential buildings can help overcome these challenges by enabling Heat Demand Shifts (HDS) to off-peak times, reducing the magnitude of the peak loads, and the difference between the peak and off-peak loads. To be effective a wide scale uptake of TES would be needed. For this to happen, the benefits and impacts of TES both for the demand side and the supply side have to be explored, which could vary considerably given the diverse physical, thermal, operational and occupancy characteristics of the UK housing stock. A greater understanding of the potential consequence of TES in buildings is necessary. Such knowledge could enable appropriate policy development to help drive the uptake of TES or to encourage development of alternative solutions. Through dynamic building simulation in TRNSYS, this work generated predictions of the space and water heating energy and power demands, and indoor temperature characteristics of the UK housing stock. Twelve building archetypes were created consisting of: Detached, semi-detached, mid-terrace and flat built forms with thermal insulation corresponding to the 1990 building regulation, and occupied floor areas of 70m2, 90m2 and 150m2. Typical occupancy and operational conditions were used to create twelve Base Case scenarios, and simulations performed for 60 winter days from 2nd January. HDS of 2, 3 and 4 hours from the grid peak time of 17:00 were simulated with sensible TES system sizes of 0.25m3, 0.5m3 and 0.75m3, and water storage temperatures of 75°C and 95°C. Parametric analysis were performed to determine the impacts and benefits of: thermal insulation equivalent to 1980, 1990 (Base Case), 2002 and 2010 building regulation; locations of Gatwick (Base Case) and Aberdeen; heating durations of 6, 9 (Base Case), 12 and 16 hours per day; thermostat settings of 19°C, 21°C (Base Case) and 23°C, and number of occupiers of 1 person and 3 persons (Base Case) per household. Good correlation was observed between the simulated results and published heat energy consumption data for buildings with similar thermal, physical, occupancy and operational conditions. The results allowed occupied space temperatures and overall daily and grid peak time energy consumption to be predicted for the range of building archetypes and parameter values considered, and the TES size necessary for a desired HDS to be determined. The main conclusions drawn include: The overall daily energy consumption predictions varied from 36.8kWh to 159.7kWh. During the critical grid peak time (17:00 to 21:00) the heat consumption varied from 4.2kWh to 58.7kWh, indicating the range of energy demands which could be shifted to off-peak times. On average, semi-detached, mid-terrace, and flat built forms consumed 7.0%, 13.8% and 22.7% less energy for space heating than the detached built form respectively. Thermal insulation changing from the 1990 building regulation level to the 1980 and 2010 building regulation levels could change the mean energy use by +14.7% and -19.6% respectively. A 0.25m3 TES size with 75°C water storage temperature could enable a 2 hour HDS, shifting 4.3kWh to 11.7kWh (mean 8.7kWh) to off peak times, in all 70m2 Base Case archetypes with the 60 day mean thermal comfort of 100%, but with the minimum space temperature occasionally dropping below an 18°C thermal comfort limit. A 0.5m3 TES size and water storage of 95°C could allow a 3 hour HDS, shifting 9.8kWh to 28.2kWh (mean 18.7kWh) to off peak times, in all 90m2 Base Case archetypes without thermal comfort degradation below 18°C. A 0.75m3 TES with a 95°C water temperature could provide 4 hour HDS, shifting 13.9kWh to 47.7kWh (mean 27.2kWh) to off peak times, in all 150m2 Base Case archetypes with 100% mean thermal comfort but with the 60 day minimum temperature occasionally dropping below the 18°C thermal comfort limit in the detached built form. Improving the thermal insulation of the buildings was found to be the best way to improve the effectiveness of HDS with TES, in terms of the demand shift period achievable with minimal thermal comfort impact. A 4 hour HDS with 100% thermal comfort is possible in all 90m2 floor area buildings with a 0.25m3 tank and a water storage temperature of 75°C provided that the thermal insulation is as per 2010 building regulation. Recommendations for further research include: 1) creating larger number of archetype models to reflect the housing stock; 2) using heat pumps as the heat source so that the mean effect on the grid from electric heating loads can be predicted; 3) taking into account the costs associated with taking up HDS with TES, in terms of capital expenses and space requirement for housing the TES system; 4) considering alternative methods of heat storage such as latent heat storage to enhance the storage capacity per unit volume; and 5) incorporating zonal temperature control, for example, only heating rooms that are occupied during the demand shift period, which could ensure better thermal comfort in the occupied space and extend the demand shift period.
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Etude de la convection naturelle et de la stratification thermique dans une cavité inclinée et chauffée au milieu : application aux capteurs solaires autostockeurs / Study of convection and stratification inside a tilted cavity heated with a constant heat flux : applications to integrated collector-storage solar water heatersSwiatek, Marie 06 November 2015 (has links)
La réglementation thermique sur les bâtiments en France impose le recours aux énergies renouvelables. L'énergie solaire, à la fois thermique et photovoltaïque, présente un grand potentiel en termes de disponibilité. Néanmoins, du fait de son caractère intermittent, des systèmes de stockage associés sont nécessaires. Pour ce qui est des systèmes solaires thermiques, les capteurs solaires intégrant le stockage (CSIS) ont pour avantages une grande simplicité ainsi que des coûts réduits comparés à des systèmes plus classiques. Ils permettent également d'éviter la problématique de la mise en place du stockage, les rendant ainsi adaptés à la rénovation énergétique.Le présent travail de thèse étudie les phénomènes de convection naturelle dans une cavité fermée à haut rapport de forme (H/L = 13) représentant le réservoir de stockage d'un CSIS. Dans un premier temps, un état de l'art des systèmes existants ainsi qu'une étude bibliographique de l'étude de ces systèmes et des phénomènes s'y déroulant sont réalisés. Il y est mis en évidence l'importance de la stratification des températures au sein du réservoir pour l'amélioration des performances globales du système. Dans un second temps, une étude expérimentale de la cavité est effectuée pour la compréhension des écoulements liés à la mise en place d'une stratification thermique satisfaisante, ainsi que des paramètres pouvant l'influencer. Dans cette étude, une plaque de stratification est ajoutée à l'intérieur de la cavité pour canaliser le fluide chaud ascendant, limitant ainsi le brassage. La zone de chauffe représentant l'échange entre la boucle solaire et le réservoir est placée au milieu de la face supérieure du système, résultant en une bonne stratification. Un écoulement inverse est observé au niveau de la sortie de ce canal. Ce phénomène est principalement responsable de l'écart de température obtenu entre le haut et le bas du système. Une étude numérique CFD du système a donc été conduite pour étudier l'influence de différents paramètres sur le comportement thermique et de l'écoulement. La diminution de l'écoulement inverse permet une meilleure circulation du fluide dans la globalité du système. Afin de déterminer si la stratification thermique observée dans le système de stockage conduit à une performance énergétique annuelle satisfaisante du capteur auto-stockeur, une modélisation nodale a été effectuée. Différents paramètres tels que la position de la zone d'échange entre le collecteur et le réservoir de stockage, ou encore l'épaisseur de l'isolant ont été étudiés pour quantifier leur influence sur les performances du système complet. / Thermal regulation for dwellings in France makes the resort to renewable energy mandatory. Solar energy has an important potential regarding its availability, for both thermal and photovoltaic applications. However, due to its intermittency, there is a need for a storing device. Concerning solar thermal systems, Integrated Collector Storage Solar Water Heaters (ICSSWH) have the advantage of a simple design and use combined with reduced costs compared to more classical devices. These systems also enable to avoid the problem of finding space for the installation of a storage system in an existing building, making them more suitable for energy renovation of houses.This present work studies the phenomena of natural convection in an enclosed cavity with high aspect ratio (H/L = 13) representing the storage of an ICSSWH. Firstly, a state of the art of existing systems as well as a literature review of these systems and of the phenomena occurring in them are conducted. The importance of thermal stratification inside the storage tank for the increase of global efficiency for the whole system is highlighted. Secondly, an experimental study of the cavity is performed to understand the fluid flow linked to the satisfying stratification obtained in the system, and find the parameters influencing it. In the experimental setup, a stratification plate is added inside the cavity to harness the ascending hot flow, hence limiting the mixing of fluid which is responsible for the destratification. The heated zone, which represents the exchange between the solar collector and the storage, is placed in the middle of the upper wall of the system, resulting in a good thermal stratification. A reverse flow can be observed at the channel outlet, which is the main parameter for the high temperature difference obtained between the top and the bottom of our system. A CFD study of the experimented system is then conducted to determine the influence of several parameters on the thermal and fluid flow behavior of the system. The decrease of reverse flow allows a better loop of the fluid in the whole cavity. In order to discover whether the thermal stratification observed in the storage leads to a better annual efficiency for the whole ICSSWH, a nodal model is used. Several parameters such as the position of the heat exchange zone between the collector and the storage or the insulation thickness are studied to quantify their influence on thermal stratification, and hence on the overall efficiency of the system.
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Processo de condicionamento e avaliação do equilíbrio térmico de bovinos Guzerá / Conditioning process and evaluation of thermal equilibrium Guzerá cattleCamerro, Leandro Zuccherato [UNESP] 12 July 2016 (has links)
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Previous issue date: 2016-07-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste estudo foi validar o condicionamento dos animais e o desenvolvimento de pesquisas que visem entender as respostas do equilíbrio térmico de bovinos Guzerá (Bos indicus), em consequência das variações meteorológicas ao longo do dia, em ambiente tropical e a emissão de metano. Foram avaliados dez bovinos da raça Guzerá, cinco machos e cinco fêmeas, com média de vinte meses, alojados em baias individuais, protegidos da radiação solar. A frequência respiratória, volume respiratório corrente, a produção de calor metabólico e a perda de calor latente via sistema respiratório, foram determinados usando um sistema de calorimetria indireta, com o auxílio de uma máscara facial. Simultaneamente, foram analisadas a temperatura retal (TR), temperatura da epiderme (TEP), temperatura do pelame (TS), temperatura do ar expirado (TEXP), além das variáveis meteorológicas, temperatura do ar (TA), umidade relativa (UR), radiação solar (RS), e temperatura radiante média (TRM). Também foram determinados os fluxos de calor por radiação e convecção. As temperaturas do ar expirado, do pelame e da epiderme, se mostraram dependentes da temperatura do ar, aumentando de 28 a 35°C, 31 a 38°C e 33 a 38°C, respectivamente, quando a temperatura do ar aumentou de 25 para 34°C, enquanto que a temperatura retal foi dependente da hora do dia. A produção de calor metabólico apresentou média de 115 e 155 W m-2 , para machos e fêmeas, respectivamente, e não se alterou com o aumento da temperatura do ar (25-34°C), o mesmo ocorreu para a emissão de metano e a frequência respiratória, para ambos os sexos. Este fato pode ser explicado pela capacidade de bovinos zebu estocarem calor. / The aim of this study was to validate the conditioning of animals and the development of research aimed at understanding the responses of the thermal equilibrium of Guzerá cattle (Bos indicus), as a result of weather variations throughout the day in a tropical environment and the methane emission. Evaluated ten Guzerat cattle, five males and five females, with an average of twenty months, housed in individual pens, protected from direct solar radiation. The respiratory rate, tidal respiratory volume, metabolic heat production and loss of latent heat via the respiratory system, were determined using an indirect calorimetry system with the aid of a facial mask. At the same time, we analyzed the rectal temperature (TR), skin surface temperature (TEP), hair coat temperature (TS), expired air temperature (TEXP), besides meteorological variables, air temperature (TA), relative humidity (UR) , solar radiation (RS), and mean radiant temperature (TRM). It was also determined heat flow by radiation and convection. The expired air temperature, hair coat temperature and skin surface temperature, proved to be dependent on air temperature, adding 28 to 35 ° C, 31 to 38 ° C and 33 to 38 ° C, respectively, when the air temperature increased from 25 to 34 ° C. While the rectal temperature is dependent on the time of day. The metabolic heat production averaged 115 and 155 W m-2 for males and females, respectively, and did not change with increasing air temperature (25-34 ° C), the same was true for emission of methane and respiratory rate, for both sexes. This fact can be explained by the ability of zebu cattle, heat stocked.
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Mecanismos termorreguladores de cabras da raça Saanen -Oliveira, Auriclécia Lopes de. January 2007 (has links)
Resumo: Foi estudada a eliminação de calor latente e estimado o fluxo térmico total ao sol e à sombra em cabras da raça Saanen mantidas em ambiente tropical, visando determinar importância da termólise evaporativa para esses animais e proporcionar subsídios para o estabelecimento de métodos de manejo em ambiente tropical. A evaporação total foi determinada por processo gravimétrico, usando-se um sistema de pesagem de precisão. A evaporação cutânea foi obtida por determinação direta através de uma cápsula ventilada; e a evaporação respiratória estimada a partir do fluxo térmico entre aparelho respiratório e o ambiente; determinaram-se ainda a estocagem térmica e as trocas convectivas e radiativas. Por ocasião de cada determinação, foram registradas a temperatura retal, a freqüência respiratória e a temperatura da superfície corporal, bem como variáveis ambientais: temperatura e umidade do ar, velocidade do vento e temperatura do globo negro. Foram avaliadas as características morfológicas do pelame (espessura da capa, comprimento médio, densidade numérica e ângulo dos pêlos) para cada animal. As análises estatísticas basearam-se no método dos quadrados mínimos para dados não-balanceados, tendo o modelo linear geral proposto incluído os efeitos: ambiente (fixo), animal (aleatório), interação animal x ambiente e regressão sobre a temperatura do ar, a umidade relativa, a temperatura radiante média, a temperatura da superfície corporal, a temperatura retal, a freqüência respiratória e a idade do animal, além das características morfológicas do pelame, no caso da evaporação cutânea. A termólise evaporativa compreendeu 61,5% da perda de calor para o ambiente, sendo a única via de perda térmica possível ao sol sob temperaturas radiante média acima de 35ºC...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work aimed at to study the elimination of latent heat and esteem the total thermal flow to the sun and the shade in Saanen goats in tropical environment, to determine importance of evaporative heat loss these animals and to provide subsidies for the establishment of methods of handling in tropical environment. The total evaporation was determined by means of gravimetrical process, for a weighing system of precision. The cutaneous evaporation was gotten by direct determination, by means of a ventilated capsule; the respiratory evaporation gotten by calculations of heat flow of respiratory device for environment. It was determined still the heat storage and the convective and radiative exchanges. For occasion of each determination, the rectal temperature, respiratory rate and surface temperature of the animal, as well as meteorological data: air temperature, relative humidity, wind speed and black globe temperature were register. The morphologic characteristics of the hair coat (coat thickness, hair length, numerical density and hair angle to skin) had been evaluated for each animal. The statistical analyses were carried through by the lest-squares method for not-balanced data. The considered model included the effect of environment and animal and the covariates: air temperature, relative humidity, mean radiating temperature, surface temperature, rectal temperature, respiratory rate and age of animal, beyond the morphologic characteristics of the hair coat for cutaneous evaporation. Heat loss evaporative understands 62.2% of the heat carried for environment exchange, being the way possible to the sun under radiant temperatures above of 35º...(Complete abstract, click electronic access below) / Orientador: Roberto Gomes da Silva / Coorientador: Danísio Prado Munari / Banca: Iran Jose Oliveira da Silva / Banca: Orlando Rus Barbosa / Banca: Isabel Cristina Boleli / Banca: Renato Luis Furlan / Doutor
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Implementação de uma bancada de ensaios para analise de estrategias de controle de sistemas de refrigeração e ar condicionado / Conditioned air system control analysis with termical storage in a ice storageCarvajal Florez, Fabio Alejandro 27 February 2004 (has links)
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Previous issue date: 2004 / Resumo: No presente trabalho se realiza o estudo do controle da válvula de expansão e da velocidade de rotação do motor do compressor para um sistema de ar condicionado com armazenamento térmico em banco de gelo. Utilizando os princípios de projeto térmico, projeto eletrônico, programação de computadores e técnicas de controle procuram-se o aumento da eficiência do sistema. Neste controle propostos usou-se a lógica difusa. Inicialmente controlou-se o grau de superaquecimento através do controle da abertura da válvula de expansão e trabalhando o compressor em sua rotação máxima. Em seguida foi implementado um controle que trabalha regulando simultaneamente a velocidade do compressor e a abertura da válvula de expansão / Abstract: In this work is realized a control analysis ofthe expansion valve and the rotacional speed of the compressor engine for an air conditioning system with thermal storage in an ice storage tank. The thermal project, electronical project, computer programming and control technics are integrated to increase the performance of the system. To implement the proposed controls the logic fuzzy is used. Inicially, the refrigerant superheat was controlled through the expansion valve with the compressor working at highest rotational speed. Then, it was implemented the control regulating simultananeously the compressor speed and the expansion valve / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica
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[en] HEAT TRANSFER DURING THE FUSION IN A VERTICAL CYLINDRICAL GEOMETRY / [pt] TRANSFERÊNCIA DE CALOR DURANTE A FUSÃO EM GEOMETRIA CILÍNDRICA VERTICALANTONIO CESAR PINHO BRASIL JUNIOR 19 March 2018 (has links)
[pt] Uma análise experimental é desenvolvida para avaliação da transferência de calor durante a fusão ao redor de um cilindro isotérmico vertical imerso em um meio de mudança de fase. A posição e forma da interface sólido-líquido é determinada como função do tempo, para diferentes temperaturas do cilindro. A relação altura/diâmetro é de cinco, para comparação com resultados já existentes. A faixa de Número de Stefan investigado foi de 0,017 a 0,33 o que equivale a uma faixa de Número Rayleigh de 7x10 elevado a quarta potência a 2x10 elevado a sexta potência. Os dados obtidos foram utilizados para a determinação dos números de Nusselt locais na interface e médios para a superfície do cilindro. A dependência da massa fundida com o tempo foi também determinada, parametrizada por Rayleigh. Soluções do problema de fusão sem os efeitos de convecção natural (Problema tipo STEFAN) foram obtidos via método de elementos finitos e estes resultados foram comparados com os dados experimentais obtidos. Isto permitiu a determinação do tempo quando os efeitos de convecção natural tornam-se importantes. Comparações com resultados numéricos publicados, para a mesma condição física, foram desenvolvidas obtendo excelentes concordâncias. / [en] An experimental investigation was performed to determine heat transfer coefficients during the outward melting of a phase-change material (PCM),maintained at its fusion temperature, around an isothermal cylinder positioned vertically. The position and shape of the Solid-liquid interface were determined as a function of time, for diferent temperatures of the cylinder. The ratio height-to-diameter of the cylinder was chosen to be five, in order to allow comparisons with available results. The Stefan number range investigated was 0,017 - 0,33 corresponding to a Rayleigh number variation from 7x10 to the fourth power to 2x10 to the sixth power. The data obtained was used in the determination of local Nusselt numbers for the interface and average Nusselt numbers for cylinder surface. The dependence of the molten mass on time was also determined, for several combinations of the relevant parameters. Solutions of the axisymmetric melting problem without natural convection effects (Stefan-like problem) were obtained via finite-element analysis. These numerical results were compared with the experimental data, which permitted the determination of times when the natural convection effects in the liquid region become of importance. The experimental data were compared with the results of an available numerical analysis of the same physical situation, and excellent agreement was obtained.
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Využití změny skupenství při akumulaci tepla v solárních vzduchových systémech / Latent heat thermal storage in solar air systemsSúkup, Tomáš January 2012 (has links)
In this paper an overview is prepared for the possibility of heat accumulation in the use of heating and hot water. In the next section is designed heat accumulator uses PCM materials for solar air system. Its properties are experimentally verified.
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Vysokoteplotní zásobník energie s celoročním provozem ve spojení se solárním systémem / High temperature energy reservoir with year-round operation in conjunction with a solar systemHoc, Pavel January 2017 (has links)
In this thesis I deal with the issue of stand-alone solar system development. This system ensures the supply of all the energy needed for a reference house. It consists of a solar concentrator and a heat reservoir. I used mathematical models to solve this issue. The calculations showed, that the concentration of solar radiation into the heat reservoir can usually achieve 69 % efficiency. The efficiency can be even higher when using a very reflective materials of the solar concentrator. In this thesis, the thermal reservoir is described and its improvements are suggested based on the optimization calculations. Thanks to knowledge gained during solving this issue, a prototype of the stand-alone solar system is going to be built. All findings will be experimentally verified with this prototype.
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Análise exergética e termoeconomia : sistematização crítica da produção científica/Tuna, Celso Eduardo. January 2019 (has links)
Resumo: Este texto descreve as linhas de pesquisa em que o autor atuou após o seu doutorado relacionadas a área de energia, abrangendo os seguintes tópicos: análise exergética e análise exergoeconômica. As produções científicas aqui descritas foram resultados obtidos a partir das pesquisas do autor e de orientações de alunos de pós-graduação, além de resultados de colaborações com outros pesquisadores do grupo de pesquisa que participa. Dentre as principais contribuições dos artigos publicados, estão o desenvolvimento e aplicação de metodologia de análise exergoeconômica para diversas configurações de sistemas de geração de energia térmica e elétrica, e também a participação na construção de um protótipo reformador a vapor de biogás e de um gaseificador de leito fluidizado no Laboratório de Otimização de Sistemas Energéticos da UNESP, campus de Guaratinguetá. O autor está classificado na base Scopus com um índice h igual a 9, e no Google Acadêmico com um índice h igual a 11, demonstrando a relevância de suas 19 publicações em revistas indexadas de elevado fator de impacto / Abstract: This text describes the lines of research in which the author acted after his doctorate related to the energy area covering the following topics: exergetic analysis and exergoeconomic analysis. The scientific productions described herein were results obtained from the author's research and guidance from graduate students, besides the results of collaborations with other researchers from the research group that participates. Among the main contributions of the articles published, are the development and application of exergoeconomic analysis for various configurations of thermal and electrical generation systems, and also the participation in the construction of a biogas steam reformer prototype and a fluidized bed gasifier in the Energy Systems Optimization Laboratory of UNESP, Guaratinguetá campus. The author is classified in the Scopus base with an h index of 9, and in Google scholar with an h index equal to 11, demonstrating the relevance of its 19 publications in indexed journals with high impact factor
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Litteraturstudie om latent värmelagrings roll i framtiden / Literature study on the role of latent heat storage in the futureKristiansson, Marcus, Karem, Agri January 2018 (has links)
Idag står världen inför en rad olika miljörelaterade problem. Ett av dessa och det kanske mest omtalade är hur utsläpp av växthusgaser sakta men säkert höjer planetens medeltemperatur. Hållbar utveckling är ett begrepp som driver diskussionen framåt om vad vi behöver göra och hur vi behöver förändras för att lösa problemen. Växthusgaserna och deras hot mot klimatet är starkt relaterat till energi. Förnyelsebara energikällor skulle kunna vara en dellösning på problemet men de kräver energilagring av olika former för att kunna ersätta sina fossila konkurrenter. Termisk energilagring är ett sätt att lagra energi på och kan delas upp i tre olika grupper. Dessa är sensibel, latent och termokemisk värmelagring. Syftet med denna litteraturstudie var att kartlägga olika applikationer av latent värmelagring som kan bidra till ett mer hållbart samhälle i framtiden. Resultatet visar att det finns många olika typer av så kallade fasomvandlingsmaterial (PCMs). Beroende på vid vilka temperaturer värme ska lagras vid används olika PCMs. PCMs kan användas för latent värmelagring inom många olika områden. Byggnader är ett av dessa områden där PCMs kan användas för att kyla och värma utrymmen antingen genom integration i ventilationssystem eller i själva byggnadsmaterialen. Latent värmelagring kan också användas i termiska solkraftverk. Latent värmelagring har på senare tid fått stor uppmärksamhet tack vare PCMs förmåga att lagra värme i små volymer och under konstant temperatur. Dock möter tekniken problem vid värmeöverföringen vilket t.ex. är fallet i lagring av termisk solenergi. Forskning pågår därför för att generellt höja PCMs termiska egenskaper. Ett exempel på detta är Nano-PCM. Resultatet visar även att latent värmelagring idag används av företag som affärsidé för olika tillämpningar. Från resultatet går det att dra slutsatsen att latent värmelagring används idag men att det krävs ytterligare forskning för att tekniken ska kunna konkurrera med andra värmelagringsmetoder. / Today, the world faces a number of environmental-related problems. One of these and perhaps most discussed is how emissions of greenhouse gases slowly but surely raise the planet’s average temperature. Sustainable development is a concept that drives the discussion forward and tells us what we need to do and how we need to change to solve the problems. Greenhouse gases and their threats to the climate are strongly related to energy. Renewable sources of energy could be a partial solution to the problem, but they require energy storage of different forms to replace their fossil competitors. Thermal energy storage is a way of storing energy and can be divided into three different groups. These are sensible, latent and thermochemical heat storage. The purpose of this literature study was to map different applications of latent heat storage that can contribute to a more sustainable society in the future. The result shows that there are many different types of phase changing materials (PCMs). Depending on the temperature at which heat is to be stored, different PCMs are used. PCMs can be used for latent heat storage in many different areas. Buildings are one of these areas where PCMs can be used to cool and heat spaces either through integration into ventilation systems or in the building materials itself. Latent heat storage can also be used in thermal solar power plants. Latent heat storage has recently received great attention thanks to PCMs ability to store heat in small volumes and under constant temperature. However, the technology is experiencing problems in the heat transfer, such is the case in the storage of thermal solar energy. Research is therefore ongoing to generally increase PCMs thermal properties. An example of this is Nano-PCM. The result also shows that latent heat storage today is used by companies as a business concept for various applications. From the result, it can be concluded that latent heat storage is used today, but that further research is required for the technology to compete with other heat storage methods.
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