L´intérêt grandissant pour les bâtiments à haute efficacité énergétique nécessite le développement de nouveaux types d´enveloppe active et multifonctionnelle pouvant couvrir une partie des besoins énergétiques du bâtiment. Les travaux présentés dans cette thèse concernent le développement de capteurs hybrides solaires photovoltaïques thermique pour la production simultanée d´eau chaude sanitaire et d´électricité au sein d´un unique capteur. L’objectif de cette thèse a été dans un premier temps d´analyser la faisabilité et la complexité du concept de capteur hybrides PV-T. Puis, à partir d’un modèle numérique développé spécifiquement pour appuyer la phase de conception du capteur PV-T les raisons expliquant la limitation des performances de tels capteurs ont été analysées, pour enfin proposer différentes solutions innovantes, tant au niveau des cellules solaires que des matériaux du modules PV et du design du capteur final afin d´en augmenter les performances. L´approche développée est par conséquent multi-échelle allant de la prise en compte des phénomènes physiques pris isolément, des propriétés locales des matériaux jusqu’à la mise en œuvre d’un composant et à l´analyse énergétique et exergétique de ses performances dans un environnement numérique dédié au bâtiment. / In the context of greenhouse gas emissions and fossil and fissile resources depletion, solar energy is one of the most promising sources of power. The building sector is one of the biggest energy consumers after the transport and industrial sectors. Therefore, making use of a building’s envelope (façades and roofs) as solar collecting surfaces is a big challenge facing local building needs, specifically in regard to heat, electricity and cooling. However, available surfaces of a building with suitable orientation are always limited, and in many cases a conflict occurs between their use for either heat or electricity production. This is one of the reasons why the concept of a hybrid photovoltaic-thermal (PV-T) collector seems promising. PV-T collectors are multi-energy components that convert solar energy into both electricity and heat. In fact, PV-T collectors make possible the use of the large amount of solar radiation wasted in PV modules as usable heat in a conventional thermal system. Therefore, PV-T collectors represent in principle one of the most efficient ways to use solar energy (co-generation effect). However, such a concept still faces various barriers due to the multidisciplinary knowledge requirements (material, semi-conductors, thermal) and to the complexity of the multiple physical phenomena implied in such concepts.The objective of this PhD work is to carry out a study based on a multi-scale approach that combines both numerical and experimental investigations regarding the feasibility of the concept of hybrid solar collector. The performance of such components is estimated through an appropriate design analysis, and innovative solutions to design an efficient PV-T collector are presented. Based on improved processing methods and improved material properties, an efficient covered PV-T collector has been designed and tested. This collector was made of PV cells connected to the surface of an optimized flat heat exchanger by an improved lamination process and covered on the front side by a static air layer and AR-coated glass pane and on the back side by thermal insulation material. The results showed a significant improvement of both thermal and electrical efficiency in comparison to all previous works on PV-T concepts found in the literature. System simulations were carried out for a hot water system with the software TRNSYS in order to get a clearer statement on the performance of PV-T collectors. The results show that the integration of PV-T collectors can be more advantageous than standard solar components in regard to thermodynamic considerations (energy and exergy) and environmental considerations (CO2 and primary energy saving).

Despite the fact that cogeneration (CHP) and tri-generation (CHCP) are among the most efficient ways to produce electricity and thermal energy, there is still some unexploited potential for these techniques. One could say that the circumstances for using these techniques are better now than ever. Some of the reasons for applying CHP and CHCP are: the techniques are well understood, their application could generate some profit, and the required technology is available. Moreover, there is increasing concern in regards to energy security, the need to increase the energy efficiency in power generation and distribution as well as to lower the emissions from fossil fuel combustion. CHP/CHCP promoters and developers face difficulties when analyzing the conditions and proposing a plan of application. On one hand, there are some external barriers which have to be torn down by means of energy regulation schemes. These may include economic incentives, easy and safe interconnection to the grid to export electricity and have backup if necessary, and access to the market to sell the surplus of electricity at a fair price. On the other hand, there are some internal barriers such as the difficulty evaluating potential energy savings, emission reduction, and economic performance of a project based on the circumstances of a specific site; lack of awareness; unwillingness to invest in CHP/CHCP projects; and difficulty in selecting and sizing the equipment which would give the maximum benefits in terms of life cycle cost, energy savings and emission reduction. Nowadays, it is possible to develop software tools which use simulations and optimization algorithms to evaluate several options, compare them and chose the ones that give the optimum performance with respect to an objective function defined by the user. In this project, the general context for the application of cogeneration and tri-generation projects was studied including factors which have an impact on its feasibility and performance. Moreover, a survey of the exiting feasibility analysis tools was done, and a case study was chosen and analyzed. Next, a model was developed using the software Trnsys for the simulation and Matlab for the optimization. The model was tested by evaluating the study case. The result of the simulation and optimization gives several possible equipment size combinations. The tradeoff between two different objective functions such as net present value and primary energy savings or emission reduction is presented in Pareto front diagrams. The main conclusion of this project is that by using Trnsys and Matlab, it is possible to develop more complex models which, when applying optimization algorisms, could become a very useful and helpful tool that CHP/CHCP developers could use to speed up the analysis of projects while contributing to the goal of deploying these techniques.

In order to contribute to reducing the CO2 emissions related to heating in housing buildings, PVT+GSHP systems appear to be interesting solutions and therefore need to be further investigated to optimise their design and increase their deployment on the field. This thesis focused on building PVT model, using the ISO9806:2017, to be integrated in a PVT+GSHP model and determining optimal PVT design parameters for this system. The most determining coefficient being the peak collector efficiency η0 it seems important to maximize it, which would mean a higher quality of solar energy collected by the collector.  The mentioned different coefficients need to be determined using labratory tests detailed in the ISO standard. The choice of the test conditions is important in order to increase the accuracy of the results, mainly when it comes to choosing the mass flow rate which should be clolse to the use conditions. If the PVT module is to be used with another mass flow rate, a correction factor would need to be applied to the coefficients to reflect the behaviour of the PVT in the use conditions.  Finding the optimal PVT array mass flolw rate is important as it enables greater energy saves. In the case presented in the thesis, a mass flow of about 60 l/(h.m²) seems to be the optimal value. A PVT oriented to the South would also guarantee higher saves. / För att bidra till att minska koldioxidutsläppen i samband med uppvärmning av bostadshus verkar PVT+GSHP-system vara intressanta lösningar och behöver därför undersökas ytterligare för att optimera deras utformning och öka deras användning på fältet. Denna avhandling fokuserade på att bygga en PVT-modell, med hjälp av ISO9806:2017, som ska integreras i en PVT+GSHP-modell och bestämma optimala PVT-designparametrar för detta system. Den mest avgörande koefficienten är den maximala solfångareffektiviteten η0 och det verkar viktigt att maximera den, vilket skulle innebära en större mängd solenergi som samlas in av solfångaren.  De olika koefficienterna måste bestämmas med hjälp av laboratorietester som beskrivs i ISO-standarden. Valet av testförhållanden är viktigt för att öka resultatens noggrannhet, främst när det gäller att välja massflödeshastigheten som bör ligga nära användningsförhållandena. Om PVT-modulen ska användas med ett annat massflöde måste en korrigeringsfaktor tillämpas på koefficienterna för att återspegla PVT-modulens beteende under användningsförhållandena.  Det är viktigt att hitta det optimala massflödet för PVT-modulen eftersom det möjliggör större energibesparingar. I det fall som presenteras i avhandlingen verkar ett massflöde på cirka 60 l/(h.m²) vara det optimala värdet. En PVT som är orienterad mot söder skulle också garantera högre besparingar.

The main objective of this thesis research is to test the applicability of a novel heat and moisture transfer panel (HAMP) in an office building to control the space humidity. A HAMP is a panel that uses a liquid desiccant to add or remove heat and moisture to or from a space. This thesis research uses the TRNSYS computer package to model an office building in four different cities representing four climatic conditions. The cities are Saskatoon, Saskatchewan; Chicago, Illinois; Phoenix, Arizona; and Miami, Florida; representing cold-dry, cool-humid, hot-dry, and hot-humid climates, respectively. The HAMP is employed in the office building with a radiant ceiling panel (RCP) system. Three other HVAC systems are examined and compared to the system employing the HAMP. The systems are: a conventional all-air system, a RCP system with 100% outdoor air, a RCP system with a parallel dedicated outdoor air system (DOAS), and the RCP system with the HAMP and 100% outdoor air. In the latter, the HAMP covers 10% of the ceiling area and uses lithium chloride solution as the liquid desiccant at different temperatures and concentrations. The results show that the HAMP is able to control the space humidity within the control limits in all climates. The HAMP also shows the ability to provide better humidity control than the other systems as it directly responds to the space latent loads. The HAMP is able to control the relative humidity between 26% RH and 62%, 24% RH and 57% RH, 27% RH and 60%, and 40% RH and 62% RH in Chicago, Saskatoon, Phoenix, and Miami, respectively. The HAMP is able to achieve a relative humidity of 35% in Chicago, Saskatoon, and Phoenix for 14%, 13%, and 20% of the working hours of the year, respectively. It is also able to achieve a relative humidity of 60% in Chicago, and Miami 10% and 55% of the working hours of the year, respectively. The results also show the potential of the RCP system with the HAMP to reduce the total energy consumed by a conventional all-air system in the hot climates by 40%, and 54% in Miami and Phoenix respectively, and in the cold climates by 14% and 23% in Saskatoon and Chicago, respectively.

In a northern European climate a typical solar combisystem for a single family house normally saves between 10 and 30 % of the auxiliary energy needed for space heating and domestic water heating. It is considered uneconomical to dimension systems for higher energy savings. Overheating problems may also occur. One way of avoiding these problems is to use a collector that is designed so that it has a low optical efficiency in summer, when the solar elevation is high and the load is small, and a high optical efficiency in early spring and late fall when the solar elevation is low and the load is large.The study investigates the possibilities to design the system and, in particular, the collector optics, in order to match the system performance with the yearly variations of the heating load and the solar irradiation. It seems possible to design practically viable load adapted collectors, and to use them for whole roofs ( 40 m2) without causing more overheating stress on the system than with a standard 10 m2 system. The load adapted collectors collect roughly as much energy per unit area as flat plate collectors, but they may be produced at a lower cost due to lower material costs. There is an additional potential for a cost reduction since it is possible to design the load adapted collector for low stagnation temperatures making it possible to use less expensive materials. One and the same collector design is suitable for a wide range of system sizes and roof inclinations. The report contains descriptions of optimized collector designs, properties of realistic collectors, and results of calculations of system output, stagnation performance and cost performance. Appropriate computer tools for optical analysis, optimization of collectors in systems and a very fast simulation model have been developed.

This report aims to study how the indoor climate in a conference room can be improved by the use of phase change material (PCM). The study includes an experiment where 40 kg of salt hydrate based PCM was placed within a conference room located in an office in the city of Uppsala, Sweden. The experiment resulted in a decrease in the peak temperature with respect to the internal heat gains in the conference room and a slower temperature increase with PCM implemented. The report concludes that PCM can improve the indoor climate in regard to its ability to limit the temperature fluctuation. The study also contains modelling and simulation over the office and conference room in the program Trnsys. This was carried out to study how the temperature and cooling demand in the conference room and office respectively would change with a larger implementation of PCM. When 106 kg of PCM was simulated to be implemented in two of the conference room walls, the specific peak temperature was on average decreased with 0.17 °C/kW during the year. Furthermore, a decrease in the cooling demand with 16 % was achieved when implementing 1 208 kg of PCM in the internal walls of the office. This study shows that there is potential for reducing the cooling demand in the building through an implementation of PCM. Further studies with a more detailed model of the office is recommended before deciding upon if and where PCM should be implemented.

A constituição de sistemas híbridos como alternativa ao fornecimento de energia da concessionária, gerando energia própria e operando de forma isolada ou interconectada ao sistema de distribuição, tem originado estudos e implementações em nível industrial, comercial e mais recentemente residencial. A principal discussão que surge são as análises das vantagens técnicas e econômicas pela opção desse tipo de instalação. Neste trabalho, é apresentado um estudo complementar às pesquisas realizadas, onde é projetado um sistema híbrido contendo aerogeradores, painéis fotovoltaicos, processo de eletrólise, célula a combustível, microturbina a gás e geradores diesel. Esse sistema é simulado e comparado técnica e economicamente a um sistema que contém apenas geradores diesel. O sistema híbrido proposto possui uma microrrede conectada a um típico sistema de distribuição mas com um limite de demanda contratada que impede a satisfação de todas as necessidades energéticas da instalação apenas com a energia da concessionária. Procura-se avaliar os impactos técnicos e econômicos do atendimento da demanda por eletricidade através deste sistema híbrido além de executar-se a otimização, via PSO, do dimensionamento deste sistema, que utiliza uma ordem de despacho para gerenciar as mini unidades geradoras de energia. Foi utilizado o software TRNSYS devido a sua característica de permitir estimar a potência e energia produzidas no intervalo de um ano com detalhamento horário de cada recurso, considerando estimativas reais e localizadas para a disponibilidade dos recursos eólicos e fotovoltaicos. / The designing of hybrid systems as an alternative to power supply from power utility, generating their own energy in operating islanded or grid-tie to the power utility, has resulted in studies and implementations in industrial, commercial and residential level recently. The main discussion that arises is the analysis of the technical and economical advantages for this type of solution. This work presents a complementary study to the researches conducted nowadays, which is designed a hybrid system containing wind turbines, photovoltaic panels, electrolysis process, fuel cell, gas micro turbine and diesel generators. This system was simulated and was compared technically and economically to a system with only diesel gensets. The proposed hybrid system has a microrrede connected to a typical distribution system with a limited power demand value that prevents the satisfaction of all energy needs of the installation only with the utility power. This study evaluates the technical and economical impacts to meeting electric power consumption through this hybrid system and optimize using PSO, the design of this system that uses a dispatch order to manage the mini power generation units. The TRNSYS software was used due to its feature of allowing estimate the electric power and electric energy produced in one year apart with hourly details of each feature, considering actual estimates and localized availability of wind and photovoltaic resources.

With an ever-increasing need to find alternative fuels to curb the use of oil in the world, many sources have been identified as alternative fuels. One of these sources is hydrogen. Hydrogen can be produced through an electro-chemical process. The objective of this report is to model an electrochemical process and determine gains and or losses in efficiency of the process by increasing or decreasing the temperature of the feed water. In order to make the process environmentally conscience, electricity from a geothermal plant will be used to power the electrolyzer. Using the renewable energy makes the process of producing hydrogen carbon free. Water considerations and a model of a geothermal plant were incorporated to achieve the objectives. The data show that there are optimal operating characteristics for electrolyzers. There is a 17% increase in efficiency by increasing the temperature from 20ºC to 80ºC. The greater the temperature the higher the efficiencies, but there are trade-offs with the required currents.

The main objectives of this thesis are to determine if the addition of an energy wheel in an HVAC system can improve the indoor air relative humidity (RH), and perceived air quality (PAQ), as well as reduce energy consumption. An energy wheel is an air-to-air energy exchanger that transfers heat and moisture between the outdoor air entering and the exhaust air leaving a building. This thesis uses the TRNSYS computer package to model two buildings (an office and a school) in four different cities (Saskatoon, Saskatchewan; Vancouver, British Columbia; Tampa, Florida and Phoenix, Arizona).<p>The results with and without an energy wheel are compared to see if the energy wheel has a significant impact on the RH and PAQ in the buildings. The energy wheel reduces peak RH levels in Tampa, (up to 15% RH), which is a humid climate, but has a smaller effect on the indoor RH in Saskatoon (up to 4% RH) and Phoenix (up to 11% RH), which are dry climates. The energy wheel also reduces the number of people that are dissatisfied with the PAQ within the space by up to 17% in Tampa. <p>The addition of the energy wheel to the HVAC system creates a reduction in the total energy consumed by the HVAC system in Saskatoon, Phoenix and Tampa (2% in each city). There is a significant reduction in the size of the heating equipment in Saskatoon (26%) and in the size of the cooling equipment in Phoenix (18%) and Tampa (17%). A cost analysis shows that the HVAC system including an energy wheel has the least life-cycle costs in these three cities, with savings of up to 6%. In Vancouver, the energy wheel has a negligible impact on the indoor RH, PAQ and energy consumption.

The main objectives of this thesis are to determine if the addition of an energy wheel in an HVAC system can improve the indoor air relative humidity (RH), and perceived air quality (PAQ), as well as reduce energy consumption. An energy wheel is an air-to-air energy exchanger that transfers heat and moisture between the outdoor air entering and the exhaust air leaving a building. This thesis uses the TRNSYS computer package to model two buildings (an office and a school) in four different cities (Saskatoon, Saskatchewan; Vancouver, British Columbia; Tampa, Florida and Phoenix, Arizona).<p>The results with and without an energy wheel are compared to see if the energy wheel has a significant impact on the RH and PAQ in the buildings. The energy wheel reduces peak RH levels in Tampa, (up to 15% RH), which is a humid climate, but has a smaller effect on the indoor RH in Saskatoon (up to 4% RH) and Phoenix (up to 11% RH), which are dry climates. The energy wheel also reduces the number of people that are dissatisfied with the PAQ within the space by up to 17% in Tampa. <p>The addition of the energy wheel to the HVAC system creates a reduction in the total energy consumed by the HVAC system in Saskatoon, Phoenix and Tampa (2% in each city). There is a significant reduction in the size of the heating equipment in Saskatoon (26%) and in the size of the cooling equipment in Phoenix (18%) and Tampa (17%). A cost analysis shows that the HVAC system including an energy wheel has the least life-cycle costs in these three cities, with savings of up to 6%. In Vancouver, the energy wheel has a negligible impact on the indoor RH, PAQ and energy consumption.