This Masters project has involved detailed thermal analysis of a unique renewable energies building. A TRNSYS model of this building has been developed and validated by real measurements and has shown to be capable of accurately predicting room temperatures and total heat gain from a solar-thermal roofing system. Supporting experiments were conducted experimentally and numerically. An experimental solar thermal testing unit constructed for the purpose of validating the solar-thermal roof concept. This experimental apparatus has been used to evaluate the effect of various operating procedures on the total heat gain from the system under a range of meteorological conditions. The validated thermal building model is used to conduct long-term simulations to provide a measure of year-round thermal performance of the building and estimated gains from renewable energy systems. Similar techniques are used to assist in the design and optimisation of a new transportable sustainable building concept in association with StoneWood Homes. It was found that a 4.5kW BIVP/T system could supply the small building with 100% of the yearly electrical energy and space heating requirements.

Liquid desiccant air conditioning (LDAC) has received much attention in recent years. This is mainly because LDAC systems are able to control latent loads in a more energy efficient way than conventional air conditioning systems. Although many research studies have been conducted on LDAC technologies, the following gaps in the scientific literature are addressed in this thesis: (1) carryover of desiccant droplets in air streams, (2) direct comparisons between different configurations of LDAC systems, (3) fundamentals of capacity matching in heat-pump LDAC systems, (4) optimal-control strategies for heat-pump LDAC systems, and (5) importance of transients in evaluating the performance of a LDAC system. Items (1) to (4) are addressed using TRNSYS simulations, and item (5) is addressed using data collected from a field test. The use of liquid-to-air membrane energy exchangers (LAMEEs) as dehumidifiers and regenerators in LDAC systems eliminate the desiccant droplets carryover problem in air streams. This is because LAMEE separate the air and solution streams using semi-permeable membranes, which allow the transfer of heat and moisture but do not allow the transfer of the liquid desiccant. A preliminary configuration for a membrane LDAC system, which uses LAMEEs as the dehumidifier and regenerator, is proposed and investigated under fixed operating conditions in this thesis. The influences of key design and operating parameters on the heat and mass transfer performances of the membrane LDAC system are evaluated. Results show that the membrane LDAC technology is able to effectively remove latent loads in applications that the humidity to be controlled. A comprehensive evaluation is conducted in this thesis for the thermal, economic and environmental performances of several configurations of membrane LDAC systems. The solution cooling load is covered using a cooling heat pump in all systems studied, while the solution heating load is covered using one of the following five different heating systems: (1) a gas boiler, (2) a heating heat pump, (3) a solar thermal system with gas boiler backup, (4) a solar thermal system with heat pump backup, and (5) the condenser of the solution cooling heating pump. Each of the membrane LDAC systems studied is evaluated with/without an energy recovery ventilator (ERV) installed in the air handling system. The influence of operating the ERV under balanced/unbalanced operating conditions is studied. It is found that the most economic membrane LDAC system is the one which uses the evaporator and condenser of the same heat pump to cover the solution cooling and heating loads, respectively (i.e. heat-pump membrane LDAC system). No clear guidance was found in the literature for sizing the evaporator and condenser in a heat-pump LDAC system to simultaneously meet the solution cooling and heating loads. When the heating and cooling provided by the heat pump exactly match the heating and cooling requirements of the solution, the system is “capacity matched”. A parametric study is conducted on a heat-pump membrane LDAC system to identify the influence of key operating and design parameters on achieving capacity matching. It is concluded that the solution inlet temperatures to the dehumidifier and regenerator are the most influential parameters on the moisture removal rate, capacity matching and coefficient of performance (COP). Three control strategies are developed for heat-pump membrane LDAC systems, where these strategies meet the latent loads and achieve one of the following three objectives: (1) meet the sensible loads, (2) achieve capacity matching, or (3) optimize the COP. Results show that the COP of a heat-pump LDAC system can be doubled by selecting the right combination of solution inlet temperatures to the regenerator and dehumidifier. The importance of transients in evaluating the performance of a LDAC system is addressed in the thesis using a data collected from a field test on a solar LDAC system. It is found that the sensible, latent and total cooling energy, and the total primary energy consumption of the LDAC system are changed by less than 10% during an entire test day when transients are considered. Thus, it can be concluded that steady-state models are reliable to evaluate the energy performances of LDAC systems.

O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano. / This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.

O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano. / This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.

Dans le contexte énergétique actuel, les pompes à chaleur (PAC) géothermiques sont parmi les technologies les plus performantes pour augmenter l’efficacité énergétique des bâtiments. Par contre le coût initial et l’encombrement des capteurs enterrés traditionnels peuvent être un obstacle à sa diffusion sur le marché des énergies renouvelables. Pour réduire ces coût et encombrement, une réflexion sur l’adjonction d’un système d’appoint et/ou de recharge thermique du sol aux capteurs enterrés est actuellement en cours de tests. Les outils actuels de modélisation des capteurs enterrés obtiennent en effet de bons résultats mais seulement pour un dimensionnement classique en régime permanent. Les modèles existants ne permettent donc pas de représenter correctement les dynamiques rapides des échanges entre le sol et les tubes et cela est d’autant plus vrai si l’on adjoint le système de recharge solaire. Par conséquence, cette thèse a pour objectif de développer les modèles fins et dynamiques nécessaires à l’analyse des phénomènes transitoires dans les capteurs enterrés eux-mêmes. Un maillage fin, sur les bases de la triangulation de Delaunay, est choisi pour le forage ainsi que pour le sol avoisinant. Une approche numérique en 3D (FVM + FEM) peut être obtenue sur les bases de la discrétisation spatiale du domaine. Cette approche appliquée brutalement induirait des temps de calcul très élevés et de toute façon incompatible avec les moyens informatiques ordinaires. Afin de répondre à l’ensemble de ces problèmes, différentes techniques ont été utilisées afin d’accélérer le temps de calcul: décomposition de domaine, emboîtement des pas de temps de calcul pour chaque sous-domaine, réduction des modèles d’états de chaque sous-domaine et finalement couplages temporels et spatiaux des équations de transferts de l’ensemble du problème. Ce dernier est développé particulièrement sur les bases de la méthode des éléments finis. Par ailleurs, un modèle hybride est développé en combinaison de différentes approches. Une approche numérique est adoptée pour la modélisation du puits et la modélisation des transferts de chaleur dans le sol environnant est faite par l’utilisation de solutions analytiques. Ainsi, ce modèle est implanté dans TRNSYS. Une plate-forme expérimentale comprenant trois puits verticaux couplés à une pompe à chaleur géothermique est également présentée. Les résultats expérimentaux sont comparés avec les résultats de la simulation aussi bien au niveau de la température du fluide qu’à la température à différentes profondeurs dans les puits. Le modèle développé donne des résultats très similaires avec ceux qui sont obtenus grâce à l’expérimentation même lors que les pas de temps sont très petits. Il y a des choses à améliorer dans ce modèle développé, mais cela concerne essentiellement l’accélération du temps de calcul. Nous avons constaté que les modèles que nous avons dévéloppés donnent des résultats meilleurs à pas de temps courts que les modèles classiques. Il faut donc bien préciser le domaine d’utilisation de chacun des modèles: consommation sur le long terme, stratégie de contrôle de la PAC, les transferts de chaleur à l’intérieur du puits et etc. De plus, une application du modèle dans le dimensionnement d’échangeurs ainsi que l’investigation de son impact sur le sol avoisinant est également envisagée. Finalement, la méthodologie de modélisation présentée dans ce travail pourrait être aussi utilisé pour différents types d’échangeurs, ouvrant aussi la porte à une analyse fine dans le domaine géothermique. / Ground-source heat pump systems with vertical ground heat exchangers (GHE) are gaining popularity worldwide for their higher coefficients of performance and lower CO2 emissions. However, the higher initial cost of installing the borehole GHEs is a main obstacle to spread the systems. To reduce the required total GHE length and efficiently operate the systems, various systems such as hybrid ones (e.g. solar heat injection) have recently been introduced. Accurate prediction of heat transfer in and around boreholes of such systems is crucial to avoid costly overdesigns or catastrophic failures of undersized systems as it is for typical GCHP systems. However, unlike the traditional sizing methods, it is increasingly required to take into account detailed borehole configuration and transient effects (e.g. short circuit effects between U-tubes). Many of the existing GHE models have been reviewed. Some of these models have serious limitations when it comes to transient heat transfer, particularly in the borehole itself. Accordingly, the objective of this thesis is to develop a model that is capable to accurately predict thermal behaviors of the GHEs. A precise response to input variations even in a short time-step is also expected in the model. The model also has to account for a correct temperature and flux distribution between the U-tubes and inside the borehole that seems to be important in the solar heat injection case. Considering these effects in 3D with a detailed mesh used for describing the borehole configurations is normally time-consuming. This thesis attempts to alleviate the calculation time using state model reduction techniques that use fewer modes for a fast calculation but predict similar results. Domain decomposition is also envisaged to sub-structure the domain and vary the time-step sizes. Since the decomposed domains should be coupled one another spatially as well as temporally, new coupling methods are proposed and validated particularly in the FEM. For the simulation purpose, a hybrid model (HM) is developed that combines a numerical solution, the same one as the 3D-RM but only for the borehole, and well-known analytical ones for a fast calculation. An experimental facility used for validation of the model has been built and is described. A comparison with the experimental results shows that the relatively fast transients occurring in the borehole are well predicted not only for the outlet fluid temperature but also for the grout temperatures at different depths even in very short time-steps. Even though the current version of 3D-RM is experimentally validated, it is still worth optimizing the model in terms of the computational time. Further simulations with the 3D-RM are expected to be carried out to estimate the performance of new hybrid systems and propose its appropriate sizing with correspondent thermal impacts on the ground. Finally, the development of the model 3D-RM can be an initiation to accurately model various types of GHE within an acceptable calculation time.

Air source heat pumps coupled with a photovoltaic system is onefeasible technology to reduce the emissions from the building sector.These systems usually have an auxiliary heating device that is able tocover the whole heat demand on its own. Because of this, often faultsof the system go unnoticed by the user for long periods of time,decreasing the benefits of having a renewable energy electricitysource. Measuring just the solar energy yield is not sufficient, asfaults in the other parts of the system outside the solar loop caninfluence the contribution of the solar panels. Hence, it is the goalto study the overall system performance with faulty conditions in boththe photovoltaics system and the heat pump. In this paper, a detailedreview of common PV faults and detection and inspection methods isgiven in order to perform a simulation of a PV solar assisted heat pumpsystem (PV-SAHP) in study at the Catalonia Institute for EnergyResearch (IREC). The simulation model is developed with TRNSYS and thepvlib Python package. The power curves and the energy yield obtainedprovide an outline on the performance of the system when the heat pumpand the photovoltaic system are operating in faulty and non-faultyconditions. The results show the electrical energy exchange with thegrid, the self-consumed energy and how the overall system efficiency isaffected by faulty operating conditions. The economic assessment withthe NPV criteria highlights the benefits of having a defect-freephotovoltaic system.

This thesis develops a calibrated model of the Cal Poly Central Chilled Water Plant with Thermal Energy Storage for use in determining an optimal operating control strategy. The model was developed using a transient systems simulation program (TRNSYS) that includes plant performance and manufacturer data for the primary system components, which are comprised of pumps, chillers, cooling towers, and a thermal energy storage tank. The model is calibrated to the actual measured performance of the plant using the current control strategy as a baseline. By observing and quantifying areas for potential improvement in plant performance under conditions of high campus cooling load demands, alternative control strategies for the plant are proposed. Operation of the plant under each of these control strategies is simulated in the model and evaluated for overall energy and demand-usage cost savings. These results are used to recommend improvements in the plant’s current control strategy, as well as to propose an optimal control strategy that may be applied to reduce plant operating costs. The results of the model identify that the plant can perform more economically by employing more chiller power to charge the Thermal Energy Storage tank to higher capacities during overnight periods when the utility rates are lower. Staging the operation of the different chillers to more precisely follow the tank charges during these off-peak periods can ensure faster tank charging when its capacity may not be sufficient to meet the peak and part-peak cooling load demands. A proposed control strategy to accomplish this breaks the overnight Off-Peak rate period into three periods with separate control setpoints, which are designed to maintain the tank charge capacity at the minimum levels to be able to accommodate the daily campus cooling demands during peak and part-peak hours.

The master thesis will concern design of hybrid photovoltaic system for a family house with accumulation of electric energy. Three alternatives of power consumption will be made. For each alternative multiple simulations will be carried out with different amount of photovoltaic panels and batteries. The most appropriate alternative and size of photovoltaic system will be chosen based on those simulations. Finally the choice of alternative will be described.

[ES] El sistema de climatización es uno de los equipos auxiliares más importantes de un vehículo, el cual mantiene un ambiente térmicamente confortable al controlar la temperatura y la humedad relativa del aire interior, sin embargo, su utilización incrementa el consumo energético global del vehículo. En la presente tesis doctoral, se desarrolla un modelo global para calcular el consumo energético y las emisiones de CO2 del sistema de climatización de vehículos cuando estos recorren un trayecto determinado. El modelo global está comprendido de tres submodelos. El primer submodelo es un modelo térmico dinámico de la cabina de un vehículo que estima la variación de la temperatura y humedad del aire interior en función de las diferentes cargas térmicas y de las condiciones exteriores (temperatura ambiente y radiación solar). El modelo fue validado de acuerdo con dos ensayos experimentales, con y sin radiación solar. Además, el modelo calcula la demanda térmica que necesita satisfacer el sistema de climatización para mantener el interior del vehículo a una temperatura predefinida. El segundo submodelo consiste en un modelo del equipo de aire acondicionado, que contiene modelos detallados de los diferentes componentes del ciclo de compresión de vapor (compresor, evaporador, condensador, dispositivo de expansión, etc.). Este modelo genera mapas de prestaciones del equipo de aire acondicionado para diferentes condiciones de trabajo (temperaturas de entrada al evaporador y condensador, velocidad del compresor, humedad relativa, etc.). El tercer submodelo integra el modelo térmico dinámico del vehículo con el modelo del equipo de aire acondicionado. Este modelo determina las prestaciones del equipo de aire acondicionado en cada paso de tiempo, en función de la demanda de refrigeración instantánea; además, calcula el consumo y las emisiones de CO2 producidas por el sistema de climatización cuando el vehículo realiza una trayectoria definida, tomando en cuenta el tipo de accionamiento del compresor (mecánico o eléctrico) y sus respectivas eficiencias de la cadena de transformación de energía. El modelo desarrollado considera la variación de las condiciones climatológicas y los cambios de dirección que el vehículo realiza a lo largo del trayecto. Finalmente, se presenta un caso de estudio en donde se estima el consumo energético y las emisiones de CO2 del sistema de climatización de un autobús con accionamiento mecánico y eléctrico. Se consideró un autobús de 50 pasajeros que realiza un trayecto extraurbano (ida y vuelta) entre las ciudades de Valencia y Madrid en un día típico de verano. Los resultados muestran que el sistema de climatización con accionamiento mecánico consume 10.2 litros de combustible (gasoil) y emite 27.3 kg de CO2 durante el viaje de ida, asumiendo que el equipo funciona a una velocidad constante del compresor de 2000 rpm. Por otro lado, el sistema de climatización en el autobús impulsado eléctricamente consume 18.1 kWh durante el viaje de ida y genera 8,2 kg de emisiones indirectas de CO2 / [CA] El sistema de climatització és un dels equips auxiliars més importants d'un vehicle, el qual manté un ambient tèrmicament confortable al controlar la temperatura i la humitat de l'aire interior, no obstant això, la seua utilització incrementa el consum energètic global del vehicle. En la present tesi doctoral, es desenvolupa un model global per a calcular el consum energètic i les emissions de CO2 del sistema de climatització de vehicles quan aquests recorren un trajecte determinat. El model global està comprés de tres submodels. El primer submodel és un model tèrmic dinàmic de la cabina d'un vehicle que estima la variació de la temperatura i humitat de l'aire interior en funció de les diferents càrregues tèrmiques i de les condicions exteriors (temperatura ambient i radiació solar). El model va ser validat d'acord amb dos assajos experimentals, amb i sense radiació solar. A més, el model calcula la demanda tèrmica que necessita satisfer el sistema de climatització per a mantenir l'interior del vehicle a una temperatura predefinida. El segon submodel consisteix en un model de l'equip d'aire condicionat, que conté models detallats dels diferents components del cicle de compressió de vapor (compressor, evaporador, condensador, dispositiu d'expansió, etc.). Aquest model genera mapes de prestacions de l'equip d'aire condicionat per a diferents condicions de treball (temperatures d'entrada a l'evaporador i condensador, velocitat del compressor, humitat relativa, etc.). El tercer submodel integra el model tèrmic dinàmic del vehicle amb el model de l'equip d'aire condicionat. Aquest model determina les prestacions de l'equip d'aire condicionat en cada pas de temps, en funció de la demanda de refrigeració instantània; a més, calcula el consum i les emissions de CO2 produïdes pel sistema de climatització quan el vehicle realitza una trajectòria definida, tenint en compte el tipus d'accionament del compressor (mecànic o elèctric) i les seues respectives eficiències de la cadena de transformació d'energia. El model desenvolupat considera la variació de les condicions climatològiques i els canvis de direcció que el vehicle realitza al llarg del trajecte. Finalment, es presenta un cas d'estudi on s'estima el consum energètic i les emissions de CO2 del sistema de climatització d'un autobús amb accionament mecànic o elèctric. Es va considerar un autobús de 50 passatgers que realitza un trajecte extraurbà (anada i tornada) entre les ciutats de València i Madrid en un dia típic d'estiu. Els resultats mostren que el sistema de climatització amb accionament mecànic consumeix 10.2 litres de combustible (gasoil) i emet 27.3 kg de CO2 durant el viatge d'anada, assumint que l'equip funciona a una velocitat constant del compressor de 2000 rpm. D'altra banda, el sistema d'aire condicionat en l'autobús impulsat elèctricament consumeix 18.1 kWh durant el viatge d'anada i genera 8,2 kg d'emissions indirectes de CO2. / [EN] The air conditioning system is one of the most important auxiliary systems in a vehicle. It provides a thermally comfortable environment by controlling the temperature and relative humidity of the indoor air; however, its excessive use increases the overall energy consumption of the vehicle. In the present Ph.D. thesis, a global model is developed to calculate the energy consumption and CO2 emissions of the automotive air conditioning system, when the vehicle travels in a determined path. The main model comprises three sub-models. The first sub-model corresponds to a dynamic thermal model of the vehicle's cabin that estimates the temperature and humidity variation of the vehicle's interior air according to the different thermal loads and the external conditions (temperature and solar radiation). It was validated according to two experimental tests, with and without solar radiation. In addition, the model calculates the thermal demand that the air conditioning system needs to maintain the interior of the vehicle at a predefined temperature. The second submodel consists in a model of air conditioning equipment, which contains detailed models of the different components of the steam compression cycle (compressor, evaporator, condenser, expansion device, etc.).This model generates performance maps for different working conditions (evaporator and condenser inlet temperatures, compressor speed, etc.). The third submodel integrates the dynamic thermal model of the vehicle with the model of the air conditioning equipment. It determines the performance of the air conditioning system for each time step based on the cooling load. Furthermore, it calculates the consumption and emissions produced by the air conditioning system when the vehicle performs a defined path. In this study, mechanically or electrically driven compressors with their respective efficiencies of the energy transformation chain were considered. The developed model takes into account the weather conditions and changes of direction that the vehicle takes along the journey Finally, a case study is presented to analyze the energy consumption and CO2 emissions of air conditioning system for a bus driven by a mechanical or an electrical motor. A 50-passenger bus was considered in the analysis. The bus makes a round trip from Valencia to Madrid on a typical summer day. Results show that the mechanically driven bus consumes 10.2 liters of fuel (diesel) and exhausts 27.3 kg of CO2 during the outward journey. The air conditioning system, in this case, is assumed to be operating at a constant compressor speed of 2000 rpm. On the other hand, the air conditioning system in electrically driven bus consumes 18.1 kWh during the outward trip and produces 8.2 kg of indirect CO2 emissions. / Además, quiero reconocer el soporte financiero brindado por el programa de becas para estudios de posgrado “CONVOCATORIA ABIERTA 2013-SEGUNDA FASE”, que fue financiado por la SENESCYT (Secretaría de Educación Superior, Ciencia, Tecnología e Innovación) (Adjudicación No 2014-AR3R7463) de Ecuador. / Vásconez Núñez, DC. (2019). Desarrollo de un modelo para el cálculo del consumo de climatización en vehículos de pasajeros urbanos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/121133 / TESIS

In Canada 15% of greenhouse gas (GHG) emissions are produced by the residential sector’s energy demand. The majority of the energy demand is space heating which is primarily met with natural gas combustion. Motivation exists to reduce GHG emissions due to their contribution to climate change. Integrated Community Energy Harvesting (ICE-Harvest) systems seek to integrate thermal and electrical energy production, storage, redistribution, and consumption in a way that reduces GHG emissions. Borehole thermal energy storage (BTES) is implemented in ICE-Harvest systems as seasonal thermal energy storage. This thesis presents a novel model of BTES thermal response with reduced complexity to aid in early siting, design, optimization, and control systems development work for ICE-Harvest systems. The reduced model can be used to approximate periodic steady state BTES thermal response. The model provides information on average ground storage volume temperature, outlet fluid temperature, heat exchanger fluid to storage volume heat transfer rate, storage volume top loss heat transfer rate, storage volume side and bottom loss heat transfer rate, and annual thermal energy storage efficiency which aids system modelling efforts for BTES in solar thermal and ICE-Harvest systems. The reduced model is formed from a solution of the thermal energy balance equations for the BTES ground storage volume and heat exchanger fluid with simplified operating conditions for a yearly BTES charging and discharging cycle. Ground storage volume temperature is lumped as a single value. Heat transfer rates between the storage volume and the heat exchanger fluid and the storage volume and its surroundings are modelled with periodic steady state thermal resistance values for the charging and discharging timesteps. A TRNSYS DST simulation of BTES is validated against measurements from a BTES installation and TRNSYS DST is used to generate the periodic steady state thermal resistance values the reduced model requires. The periodic steady state thermal resistance values of BTES charging and discharging are dependent on BTES design parameters (spacing between boreholes, number of boreholes, borehole depth, and storage volume size) and ground thermal properties (thermal capacity and thermal conductivity) which is presented in a series of parameter sweeps with respect to a reference simulation. The reduced model predicts periodic steady state average storage volume temperature with a RMSD of 0.96°C for charging and 1.3°C for discharging when compared to the TRNSYS DST reference simulation. The reduced model predicts the periodic steady state heat exchanger total energy transfer within 1.8% for the charging timestep and 2.8% for the discharging timestep when compared to the TRNSYS DST reference simulation. The reduced model’s periodic steady state thermal resistance values are demonstrated to be independent of heat exchanger fluid inlet temperature except for the side and bottom loss thermal resistance during discharging. The reduced model cannot replicate the change in heat transfer direction that occurs during BTES discharging when the temperature of the storage volume decreases below the temperature of the surrounding ground, however, the magnitude of the energy transfer that would occur is negligible compared to the magnitude of the BTES heat exchanger total energy transfer. / Thesis / Master of Applied Science (MASc)