Search

Within the TRI-HP project, we have developed trigeneration integrated solutions based on natural refrigerant heat pumps with multiple renewable energy sources (air, ground and solar) to provide high-efficiencyheating, cooling and electricity to new and refurbished multifamily residential buildings with renewable share 80%. ThecTRI-HP solutions are the solar-ice slurry system and the dual-source heat pump system. The solar-ice slurry system consists of a natural refrigerant heat pump (either propane-R290 or CO2-R744), able to supercool water to produce ice slurry, which makes use of solar thermal collectors to regenerate the ice slurry storage used as the heat source for the heat pump. The solar thermal collectors that supply mostly heat to the ice slurry in winter can also provide direct heat to Domestic Hot Water (DHW) and Space Heating (SH) in the other seasons. The solar-ice slurry system is a meaningful concept to supply heating demands to buildings in heating-dominatedclimates with enough solar radiation in winter, as in most Central Europe regions. More specifically, the system using the CO2 heat pump is targeting new buildings with a high share of DHW demands due to the characteristics of the supercritical refrigerant cycle that undergoes a large temperature glide in the CO2 gas cooler. The other system employing the propane heat pump targets refurbished buildings with a higher share of SH. The dual-source/sink heat pump (DSHP) system, which uses a natural refrigerant propane (R290) heat pump, is able to use two renewable heat sources and sinks, e.g. ground and ambient air in the heat pump, in order to optimize heat pump operation conditions, and reduce the borehole length by up to 25%. The present deliverable compares the energetic performance and cost competitiveness of TRI-HP systems and reference systems for heating (DHW and SH), cooling and electricity based on experimental and numerical analyses. There are two main reference systems to which TRI-HP systems are compared: the conventional solar-ice "ice-on-coil" system and the Ground Source Heat Pump (GSHP) system. After having performed static tests with the heat pump prototypes to verify their performance in standard, steady-state conditions, more realistic tests of the whole TRI-HP systems have been carried out to evaluate their performance in relevant dynamic boundary conditions. For this purpose, the hardware-in-the-loop Concise Cycle Test (CCT) has been applied using several representative days as the methodology to represent the whole year or a season. With this methodology, dynamic experiments of only a few days can be performed in the laboratory, allowing us to accurately characterize the system performance during the year for a specific climate and demand profile. These tests also included the electrical part, emulating the PV field and the household electricity demand, and physically installing the battery, its management and the inverter in the laboratory. The tests for the solar-ice slurry system for SH and DHW applications have been performed at the Institute for Solar Technology (SPF-OST) in Switzerland. The Swiss company HEIM AG designed and manufactured the two natural refrigerant heat pumps. The solar-ice slurry systems achieved an annual System Performance Factor (SPF) between 4 and 4.8 with the climate of Bern (Switzerland) for the CO2 and propane heat pumps slurry systems for a new and refurbished building, respectively. These energetic performances are higher than the typical values achieved by GSHP systems for this climate and equivalent demands. The tests of the dual source/sink system were performed in the SEILAB laboratory of IREC in Spain and resulted in an overall SPF of 3.7 in a Mediterranean climate where both heating and cooling were necessary. Although the SPF was expected to be higher, it was achieved with the first dual source/sink heat pump prototype. With the current results of the CCT test presented in this deliverable, we have demonstrated the autonomous operation of the complete TRI-HP systems in a relevant environment using the accelerated hardware-in-the-loop approach, including the integration of both thermal (heat pump, storage tanks, hydraulics and control) and electrical elements (battery, inverter, PV). Regarding the solar-ice slurry system, we can state that the supercoolingslurry heat pump has reached a TRL of 6, even higher than the TRL 5 expected at the proposal phase. For the complete system, we have reached a TRL of 5, as anticipated at the proposal phase. A TRL 6 was not achieved at a complete system level since the ice crystallizer and storage vessel was not physically installed. The coupling of the supercooling ice slurry heat pump with an ice crystallizer and an ice slurry storage would be the next step in future projects to bring the complete system to a TRL 6 and beyond. Regarding the dual source/sink system, a TRL of 6 has been achieved for the dual source/sink heat pump, successfully testing the whole system using the CCT method. Experimental results of the CCT have been used to validate the TRNSYS simulation models implemented in the pytrnsys framework1. For the energetic performance and cost competitiveness analysis of the TRI-HP system, different pytrnsys/TRNSYS detailed models of the TRI-HP systems and their references to compare with have been developed. The cost-competitive advantage of solar-ice slurry TRI-HP systems over the conventional solar-ice with a synthetic refrigerant has been proven. The investment costs of the solar-ice slurry TRI-HP systems are between 8% to 11% lower than the reference ice-on-coil system in Bilbao and 14% to 17% lower in Zurich. The heat generation costs in cte/kWh are between 7% to 12% lower for the slurry TRI-HP version. Furthermore, the potential for full integration of ice slurry storage into the building’s construction envisages a significant cost reduction which, not beingreachable to the conventional ice storagewould bring even a higher cost competitive advantage for the TRI-HP system. Regarding the cost-efciency competitive advantage of the solar-ice slurry TRI-HP system over the GSHP system with a synthetic refrigerant, the following can be concluded after comparing two climates and two buildings: • The energetic efficiency of the solar-ice slurry system as a dimension here is always higher than the GSHP systems, with improvements in SPF in the range of 5 % to 22 %. This might seem counterintuitive since the ground source is supposed to be a better heat source than ice. However, one needs to take into account that i) solar thermal collectors can provide heat for DHW and SH directly ii) the ice storage is typically only in ice form for three months in winter, and iii) the typical dimension of boreholes using Swiss SIA-Norm 384/6 leads to temperatures on the ground heat exchanger around 0 °C after five years, which is the same as the ice slurry source. • The investment costs of solar-ice slurry TRI-HP systems are between 13% to 29% lower compared to GSHP, and the heat generation cost are between 5% to 17% lower. However, the cost comparison results with the GSHP should be taken with caution. The cost of GSHP can vary a lot depending on the ground type, country and sizing procedure; therefore, these results can be inverted depending on conditions. What is clear is that the solar-ice slurry system developed in TRI-HP has the potential to be cost-competitive even with well-established GSHP systems that have existed on the market for decades. However, GSHP can be used for heating and cooling, while solar ice systems can only provide some free passive cooling from the ice storage in its current form. To include active cooling, one would need to add an additional air heat exchanger for heat rejection, which has not been considered within the TRI-HP project but is technically possible. The dual-source/sink heat pump system has been compared to a pure GSHP system for the climate of Zurich and the refurbished building MFB90. In this case, the borehole length could be reduced by 25%, which leads to an investment cost of the GSHP, which is 9% higher than the DSHP system. These cost reductions are expected tobe less important for climates where both heating and cooling are possible due to the regeneration of the borehole field by the cooling demands. More results of both systems are provided in the last deliverable of the TRI-HP project [2], where we have studied the benefits of all TRI-HP systems around Europe.

Within the TRI-HP project, we have developed trigeneration integrated solutions based on natural refrigerant heat pumps with multiple renewable energy sources (air, ground and solar) to provide high-efficiencyheating, cooling and electricity to new and refurbished multifamily residential buildings with renewable share 80%. ThecTRI-HP solutions are the solar-ice slurry system and the dual-source heat pump system. The solar-ice slurry system consists of a natural refrigerant heat pump (either propane-R290 or CO2-R744), able to supercool water to produce ice slurry, which makes use of solar thermal collectors to regenerate the ice slurry storage used as the heat source for the heat pump. The solar thermal collectors that supply mostly heat to the ice slurry in winter can also provide direct heat to Domestic Hot Water (DHW) and Space Heating (SH) in the other seasons. The solar-ice slurry system is a meaningful concept to supply heating demands to buildings in heating-dominatedclimates with enough solar radiation in winter, as in most Central Europe regions. More specifically, the system using the CO2 heat pump is targeting new buildings with a high share of DHW demands due to the characteristics of the supercritical refrigerant cycle that undergoes a large temperature glide in the CO2 gas cooler. The other system employing the propane heat pump targets refurbished buildings with a higher share of SH. The dual-source/sink heat pump (DSHP) system, which uses a natural refrigerant propane (R290) heat pump, is able to use two renewable heat sources and sinks, e.g. ground and ambient air in the heat pump, in order to optimize heat pump operation conditions, and reduce the borehole length by up to 25%. The present deliverable compares the energetic performance and cost competitiveness of TRI-HP systems and reference systems for heating (DHW and SH), cooling and electricity based on experimental and numerical analyses. There are two main reference systems to which TRI-HP systems are compared: the conventional solar-ice "ice-on-coil" system and the Ground Source Heat Pump (GSHP) system. After having performed static tests with the heat pump prototypes to verify their performance in standard, steady-state conditions, more realistic tests of the whole TRI-HP systems have been carried out to evaluate their performance in relevant dynamic boundary conditions. For this purpose, the hardware-in-the-loop Concise Cycle Test (CCT) has been applied using several representative days as the methodology to represent the whole year or a season. With this methodology, dynamic experiments of only a few days can be performed in the laboratory, allowing us to accurately characterize the system performance during the year for a specific climate and demand profile. These tests also included the electrical part, emulating the PV field and the household electricity demand, and physically installing the battery, its management and the inverter in the laboratory. The tests for the solar-ice slurry system for SH and DHW applications have been performed at the Institute for Solar Technology (SPF-OST) in Switzerland. The Swiss company HEIM AG designed and manufactured the two natural refrigerant heat pumps. The solar-ice slurry systems achieved an annual System Performance Factor (SPF) between 4 and 4.8 with the climate of Bern (Switzerland) for the CO2 and propane heat pumps slurry systems for a new and refurbished building, respectively. These energetic performances are higher than the typical values achieved by GSHP systems for this climate and equivalent demands. The tests of the dual source/sink system were performed in the SEILAB laboratory of IREC in Spain and resulted in an overall SPF of 3.7 in a Mediterranean climate where both heating and cooling were necessary. Although the SPF was expected to be higher, it was achieved with the first dual source/sink heat pump prototype. With the current results of the CCT test presented in this deliverable, we have demonstrated the autonomous operation of the complete TRI-HP systems in a relevant environment using the accelerated hardware-in-the-loop approach, including the integration of both thermal (heat pump, storage tanks, hydraulics and control) and electrical elements (battery, inverter, PV). Regarding the solar-ice slurry system, we can state that the supercoolingslurry heat pump has reached a TRL of 6, even higher than the TRL 5 expected at the proposal phase. For the complete system, we have reached a TRL of 5, as anticipated at the proposal phase. A TRL 6 was not achieved at a complete system level since the ice crystallizer and storage vessel was not physically installed. The coupling of the supercooling ice slurry heat pump with an ice crystallizer and an ice slurry storage would be the next step in future projects to bring the complete system to a TRL 6 and beyond. Regarding the dual source/sink system, a TRL of 6 has been achieved for the dual source/sink heat pump, successfully testing the whole system using the CCT method. Experimental results of the CCT have been used to validate the TRNSYS simulation models implemented in the pytrnsys framework1. For the energetic performance and cost competitiveness analysis of the TRI-HP system, different pytrnsys/TRNSYS detailed models of the TRI-HP systems and their references to compare with have been developed. The cost-competitive advantage of solar-ice slurry TRI-HP systems over the conventional solar-ice with a synthetic refrigerant has been proven. The investment costs of the solar-ice slurry TRI-HP systems are between 8% to 11% lower than the reference ice-on-coil system in Bilbao and 14% to 17% lower in Zurich. The heat generation costs in cte/kWh are between 7% to 12% lower for the slurry TRI-HP version. Furthermore, the potential for full integration of ice slurry storage into the building’s construction envisages a significant cost reduction which, not beingreachable to the conventional ice storagewould bring even a higher cost competitive advantage for the TRI-HP system. Regarding the cost-efciency competitive advantage of the solar-ice slurry TRI-HP system over the GSHP system with a synthetic refrigerant, the following can be concluded after comparing two climates and two buildings: • The energetic efficiency of the solar-ice slurry system as a dimension here is always higher than the GSHP systems, with improvements in SPF in the range of 5 % to 22 %. This might seem counterintuitive since the ground source is supposed to be a better heat source than ice. However, one needs to take into account that i) solar thermal collectors can provide heat for DHW and SH directly ii) the ice storage is typically only in ice form for three months in winter, and iii) the typical dimension of boreholes using Swiss SIA-Norm 384/6 leads to temperatures on the ground heat exchanger around 0 °C after five years, which is the same as the ice slurry source. • The investment costs of solar-ice slurry TRI-HP systems are between 13% to 29% lower compared to GSHP, and the heat generation cost are between 5% to 17% lower. However, the cost comparison results with the GSHP should be taken with caution. The cost of GSHP can vary a lot depending on the ground type, country and sizing procedure; therefore, these results can be inverted depending on conditions. What is clear is that the solar-ice slurry system developed in TRI-HP has the potential to be cost-competitive even with well-established GSHP systems that have existed on the market for decades. However, GSHP can be used for heating and cooling, while solar ice systems can only provide some free passive cooling from the ice storage in its current form. To include active cooling, one would need to add an additional air heat exchanger for heat rejection, which has not been considered within the TRI-HP project but is technically possible. The dual-source/sink heat pump system has been compared to a pure GSHP system for the climate of Zurich and the refurbished building MFB90. In this case, the borehole length could be reduced by 25%, which leads to an investment cost of the GSHP, which is 9% higher than the DSHP system. These cost reductions are expected tobe less important for climates where both heating and cooling are possible due to the regeneration of the borehole field by the cooling demands. More results of both systems are provided in the last deliverable of the TRI-HP project [2], where we have studied the benefits of all TRI-HP systems around Europe.

This study aims to analyze the performance of a CO2 heat pump system with an ice-slurry function, including a supercooler, a tri-partite gas cooler, and an ejector. The prototype was developed as part of the TRI-HP project. The performance tests were conducted under different operating conditions in three different modes in the laboratory. The modes are space heating (SH), domestic hot water (DHW), and parallel mode (PA), in which a simultaneous supply of DHW and SH is provided. A numerical model was also developed and verified with the test results. The results show that the developed heat pump can operate under different operating conditions successfully. It can supply hot water up to 45 °C and 70 °C for SH and DHW, respectively. The system's heating coefficient of performance (COPH) varies between 3 to 6.5 depending on operating conditions.

In the four years of duration of the TRI-HP project, two main systems have been developed with the aim of reducing installation costs compared to state-of-the-art systems with equivalent energetic performance. The two systems developed have been the solar-ice slurry system with the supercooling method and the dual source/sink system. Both systems made use of natural refrigerant heat pumps coupled with photovoltaics. The solar-ice slurry system has been developed using two heat pumps with supercoolers (acting as evaporators): i) a CO2heat pump with a transcritical cycle and a tri-partite gas cooler and ii) a propane heat pump. The dual source/sink system was developed using a propane heat pump with a reversible cycle to produce heating and cooling. The dual source/sink heat pump (DSHP) system, which uses a natural refrigerant propane (R290) heat pump, is able to use two renewable heat sources in the evaporator of the heat pump to provide heating, e.g. ground and ambient air, which are also used as heat sinks to provide cooling demands. By using two heat sources/sinks, it is possible to optimize heat pump operation's conditions and reduce the borehole length by up to 25 \%. The solar-ice slurry system is an alternative solution to ground source heat pump systems (GSHP) where the borehole field is substituted by solar thermal collectors and an ice storage, which acts as a low-temperature seasonal storage to shift summer solar heat to winter, while being partially charged/discharged on a daily basis in winter to cover periods without enough solar irradiation, e.g. nights. These continuous charge and discharge, the use of water as heat transfer medium, and the large latent heat of fusion, makes the levelized cost of storage very attractive. The solar-ice slurry system has several advantages compared to the GSHP systems: i) it does not need space to drill boreholes ii) is not affected by noise and ground water regulations and iii) it does not need to be regenerated. In the present deliverable, a cost-energetic analysis of the three TRI-HP systems for providing heating, cooling and electricity to multifamily residential buildings in different European locations is presented based on pytrnsys framework (https://pytrnsys.readthedocs.io/en/latest/)using TRNSYS as simulation core. In the previous deliverable, the pytrnsys / TRNSYS models were validated by means of experimental data obtained using the hardware-in-the-loop CCTmethod. Based on those simulation models, and with the capability to easily scale technologies and extrapolate simulations to other locations from pytrnsys, a parametric study for different Europe locations and demands has been carried out to evaluate the cost-energetic potential of TRI-HP systems around Europe. For this parametric study, 940 simulations have been carried out that lead to the conclusions summarized hereafter. The solar-ice slurry system is able to reach SPF in the order of 4 for all locations and buildings with the exception of Warsaw and Helsinki, where the low irradiation limits the use of solar heat achieving SPF above 3.5. For the DSHP, the SPF is usually lower, in the range of 3.5 to 4, due to the lack of solar collectors that can provide solar direct heat in comparison to the solar-ice slurry system. The overall SPF includes the electrical consumption of the heat pump compressor, electric back-ups, circulation of all pumps, control and penalties for not reaching the set-points. Moreover, the multi-family buildings have a constant re-circulation loop for DHW where around 15 % of the DHW is lost and has to be supplied at a high temperatures of 55-58 °C. The natural refrigerant heat pumps have shown to work very efficiently when targeting their optimum application, i.e. the CO2heat pump is best when supplying large DHW demands, and the propane is best when providing large SH demands. When not clear if DHW is high enough, then propane would be the recommended choice, since it is more flexible to provide demands at different temperature levels. The TRI-HP systems include PV and an electrical battery reaching a renewable share above 80 % with a net zero energy concept. Thus, the PV field is dimensioned to provide all electricity needed for the provision of household electricity and to drive the heating system. However, only 80 % is used on-site and the remaining 20 % is purchased from the grid and provided as feed-in in other time periods (mostly in summer). The need for purchasing electricity from the grid is due to the lack of a seasonal storage which, with today's technologies and prices, would not be cost-economic. The solar-ice slurry system using the CO2heat pump reaches energy cost for heating and electricity, including a battery and the PV field, in the range of 19-29 ct/kWhdepending on the location achieving in most cases an SPF of 4. The upper range cost is obtained in cities with low irradiation where the solar-ice system is not meant to be used, such as Helsinki or Warsaw. The lower limit of 19 ct/kWh is reached in the location of Davos (alpine) with a very high irradiation in winter together with a large heating demand due to the low temperatures. However, for simplicity, results from Davos are obtained with the assumption that snow does not cover the collectors in winter. The second lowest cost of 19 ct/kWh is reached in Madrid, which similarly to Davos, has a high irradiation in winter and a large heat demand. In this case, however, results could be achieved in practice since snow will not be present on the collector field. On the other hand, the large cooling that would be necessary in Madrid could not be covered by this system unless an additional air heat exchanger for heat rejection would be used, which has not been studied within TRI-HP project. For the other cities, the SPF ranges from 23-27 ct/kWhwith only 20~\% of electricity purchased from the grid and without considering any revenue for the 20 % of electricity feed into the grid. The large range of energy cost shows a significant influence on the weather conditions, which is clear since the system relies on solar thermal energy to drive the heat pump. The solar-ice slurry propane system reaches energy (including heat and electricity) cost in the range of 16- 27 ct/kWhfor the MFB90 depending on the location. Removing the exceptions of Warsaw, Helsinki and Davos, the energy cost ranges between 18-25 ct/kWhachieving an SPF of 4 with only 20 % of electricity purchased from the grid and without considering any revenue for the 20 % of electricity feed into the grid. Energy cost are lower for the MFB90 building since the heat demand is more distributed in shoulder seasons compared to the MFB30, where most of the energy demand is concentrated in winter, when solar irradiation is lower. As an example, the solar-ice slurry system would reach an SPF of 4 with a renewable share of 80~\% and an energy cost of 24 ct/kWhfor a new building with 43.6 kWh/(m2,y)in Brussels with a yearly heat demand of 36~MWh for space heating, 17~MWh for DHW and 16~MWh for household electricity (appliances, lighting, cooking, etc.). To achieve this large efficiency, it is necessary to install 82 m2of collector area (1.6 m2/MWhper annual SH and DHW demands) and 61 m3(1.2 m3/MWh) of ice storage volume, which could be easily integrated into the building's basement (equivalent to parking needs for two cars), as well as a PV field of 29 kWpwith a battery of 29 kWh. To achieve the target of SPF of 4 for a refurbished building with 110 kWh/(m2,y)in Brussels with a yearly heat demand of 116 MWh for space heating, the necessary collector area is 195 m2(1.5 m2/MWh) and the ice storage volume is 146 m3(1.1 m3/MWh,which equals to parking needs for five cars). To achieve a renewable share of 80 %, a PV field of 47 kWpwith a battery of 47 kWh was used leading to an energy cost of 21 ct/kWh. From the absolute values needed here one will have to think if this large collector area will fit into the roof if PV will be there too. Solutions to overcome roof competition between solar thermal and PV could be the use of hybrid PVT collectors or to use facade panels. The performance of the DSHP system is less dependent on the location and on the parametric variation (borehole length) compared to the solar-ice slurry case. For most locations the energetic efficiency SPF is in the range of 3.2 to 4. The borehole length has been sized to reach a minimum average temperature on the borehole close to 0 °Cafter 5 years for heating dominated locations and to close 2 °Cfor non-heating dominated locations. This leads to extraction powers on the borehole field between 20-80 W/mdepending on the location. The energy cost of the DSHP system is in general very good due to the possibility of providing heating and cooling, due to the large size of the building and the reduced needs of the borehole length, with energy cost ranging from 15-20 ct/kWh.

TRI-HP EU project aims to develop trigeneration integrated solutions that combine heating, cooling and electricity generation based on heat pumps running with natural refrigerants and using multiple renewable energy sources. Most of the developments of the project are focussed on the whole refrigerant cycle of the heat pumps as well as on the heat exchangers used. Three innovative heat exchangers have been designed, manufactured, and tested as stand-alone devices and implemented in heat pumps with nominal capacities of 10 kW within the current project.The experimental results of the supercoolers have been published in [1] where all experimental data used here is accessible as open data. One of the heat exchangers developed is based on brazed heat exchangers where icephobic coatings have been applied to achieve high levels of supercooling in very compact heat exchangers typically used in residential heat pumps. Several coatings were applied into plate heat exchangers, the so-called supercoolers, and were compared to each other. The best coatings were applied in the evaporators of the heat pumps that were able to supercool water in real dynamic conditions. In the present deliverable, a numerical model to predict the behaviour of supercoolers is presented and validated with experimental data. Results show that the model presented here is able to capture the main characteristics of the supercoolers assessed.The experimental results of the dual source/sink heat exchanger have been published in [2]. A second innovative heat exchanger is a dual source/sink unit able to use brine/water as well as air as heat sources and sinks for heating and cooling, respectively. The idea is to be able to use ground sources as well as ambient air as heat sources and sinks. This heat exchanger is key in the development of a dual source/sink heat pump which has been manufactured and tested. This hybrid heat pump is fully reversible, and as such, the dual heat exchanger needs to operate as an evaporator as well as a condenser. The design and sizing of this heat exchanger were based on a numerical model developed in Modelica. The numerical model, as well as its validation in heating and cooling models using both sources, is provided. The third innovative heat exchanger is specially dedicated to transcritical CO2 heat pumps. A tri-partite gas cooler has been developed to provide space heating (SH) and domestic hot water (DHW) simultaneously in a compact unit. The tri-partite gas cooler consists of three brazed heat exchangers connected in a particular form. The first gas cooler is used to preheat DHW, the second one is used to provide SH, and the third one is to reheat DHW. The three gas coolers are connected in series on the CO2 site such that the hottest part of the CO2 side is connected to the third gas cooler. The CO2 is then cooled from the gas cooler third to the one.experimental results of the tri-partite gas coolers have been published in [3].

TRI-HP EU project aims to develop trigeneration integrated solutions that combine heating, cooling and electricity generation, based on heat pumps running with natural refrigerants and using multiple renewable energy sources. Three heat pump prototypes (propane-ice, propane-dual, CO2-ice)were already analyzed in the first testing campaign. The prototypes of the proposed heat pumps were modified for the second test campaign based on the results of the first test campaign. For the enhancement of the propane-ice heat pump, the compressor and evaporator were changed. Changing the compressor brought a 5 % increase in system efficiency (COP). One expansion valve was utilized rather than two valves for simplicity, lower cost, and higher reliability. Moreover, the extraction fan operates only in case of an emergency. Although this solution slightly reduces the safety level, it increases the COP by up to 3 %. From the comparative analysis between the first and second test campaigns, it has been observed that the propane-ice heat pump COP has increased by an average of 11.3 % compared to the first prototype, for the nominal operation temperature range for SH (30/35 °C) and DHW (52/60 °C}). Finally, the casing of the prototype was changed from a high frame to a wide frame for smooth production and a lower footprint. In terms of advancing the second prototype of the propane DSHP, a DSHXwith small external tubes dimension was utilised in order to reduce the refrigerant charge amount. Only one supply port was implemented to eliminate the risk of refrigerant bypass. The exhaust distributor of the DSHXwas lower than the supply distributor. It was moved to a higher position than the supply one to lower the pressure drop and increase the evaporating temperature. The frame of the second prototype was also changed to simplify the commissioning. As far as the CO2heat pump is concerned, new and more ejectors were utilised to enlarge the application range and improve the system's performance. Evaporator control was enhanced by controlling refrigerant outlet quality along with the refrigerant pressure difference method to increase the system efficiency. The internal heat exchanger was switched with a new plate configuration. This report describes the second experimental campaign after the modification/upgrading of the heat pump prototypes. The experimental results are analysed and compared when possible with the first experimental campaign results. The main performance indicators for the three heat pumps are reported.

The object of the present study is a natural refrigerant base (propane) heat pump system with a dual source/dual sink heat exchanger (air or ground-based) which is integrated into a centralized tri-generation system with PV and battery for a multi-family building located in Spain. To evaluate the performance of this complex system, a simulation environment was developed, connecting different software. The main program is TRNSYS, with the python package pytrnsys used to create the models and run the simulations, while a model predictive controller is externalized in a separate optimization software. The co-simulation environment enables to couple both software and operate the models in the simulation with the decisions made by the external controller. This environment was used to evaluate the considered system for three separate weeks of the year, each representative of the heating/cooling/DHW demands in winter, summer and intermediate seasons. For each of these weeks, the simulation was run once with a reference rule-based controller, and once with the advanced model predictive controller, to evaluate the additional benefits brought by the later strategy. The results were then extrapolated to the whole year, and revealed that the model predictive controller was able to provide cost savings of 12 to 20% (depending on the consideration or not of the cooling season which gave unexpectedly adverse results). This controller operated the heat pump more efficiently thanks to its prior knowledge of the best source to use at each moment (air or ground). It also managed the battery in a more economical way thanks to its prior knowledge of the time-varying electricity price, thus charging always at the cheaper hours of the day, and demonstrating the advantages of using forecasts and predictive optimization for HVAC control., CLIMA 2022 conference, 2022: CLIMA 2022 The 14th REHVA HVAC World Congress

The goal of the project TRI-HP is to develop systems based on electrically-driven natural refrigerant heat pumps coupled with photovoltaics to provide heating, cooling and electricity to multi-family buildings with an on-site renewable share of 80 %. The implementation of different energy sources for such a system often leads to a complex architecture of the overall system. The performance evaluation of such systems is not trivial and cannot be done via steady-state measurements of individual components. Instead, dynamic measurements using the hardware-in-the-loop approach are performed to test the performance of the newly developed systems. A method called concise cycle test (CCT) has been developed for this purpose. This method was adapted to the systems to be tested and applied in different versions. The CCT method is based on the selection of several representative periods of the year, and shows the behaviour of a complete system for heating and cooling under relevant conditions in these periods, enabling then to extrapolate the results for a whole year operation. Two different approaches were used to select the test sequence. For the measurement of a dual source/sink system, the annual weather data were divided into four clusters, from each of which representative days were selected. For the solar-ice-slurry system, a single, contiguous test cycle of typical days from throughout the year was selected. This allows both, to test the functionality of the ice-slurry storage and the advanced energy management strategies by performing experiments only on selected days. For the tests, the complete system including a heat pump and thermal and electrical storages are installed on a test rig. The test rig emulates a building, including the space heating and cooling distribution system, the domestic hot water draw offs, the solar collector field or ground heat exchanger depending on the system tested and the photovoltaic installation. The system tested must act completely autonomously to cover the demand for heating and cooling of the building and the draw-offs during a test cycle. In this work, the methodology has been applied to two different cases of complete systems adapted to different climates (Switzerland and Spain)., CLIMA 2022 conference, 2022: CLIMA 2022 The 14th REHVA HVAC World Congress

This report summarizes the main activities carried out on the eld of supercoolers in the H2020 TRI-HP project. The overall goal of the TRI-HP project is the development of trigeneration systems based on electrically driven natural refrigerant heat pumps coupled with renewable electricity generators (PV). The systems are aiming to provide heating, cooling and electricity to multi-family residential buildings with a self-consumed renewable share of 80 %. One of the systems developed is based on a supercooling ice slurry heat pump. A successful development of such system relies on the development of a heat exchanger that can supercool water to temperatures around −2 °C to −3 °C without forming ice, the so-called supercooler. This report summarizes the development and testing results of such supercoolers. The specific goal of the project on the ice slurry field was to develop a compact and reliable supercooler to be used as an evaporator for a 10 kW heat pump using natural refrigerants heat pumps such as propane and CO2. This goal has been achieved by applying coatings (organic, inorganic or a mixture of them) on very compact flat plates heat exchangers. Results shown in this report show not only the reliability of the operation of supercoolers below 0 °C, but also prove the very ambitious measurable targets established at the project proposal phase, i.e. stable operation with a supercooling degree of 4 K. This achievement represents a significant progress respect state of the art Japanese supercoolers that operate at 2 K supercooling degree. Results achieved within TRIHP represent a ground-breaking progress in Europe where nothing similar has been achieved before. From the authors’ knowledge, the supercoolers tested here are the first operational ones at this capacity range ever develop in Europe. In this deliverable results of icephobic coated and nickel treated heat exchangers are summarized. Six heat exchanger with icephobic coatings were tested at SPF laboratories. As reference, a heat exchanger without any coating and a commercial heat exchanger coated with a ceramic anti-fouling coating was used. For coating comparison, three different chemical families were tested at three different mass flows. Experiments of coated heat exchangers show average supercooling degrees in the range of 3 K to 4 K. The anti-fouling coatings performed worse compared to the reference non coated heat exchangers with an about 70 % lower average supercooling degree. All icephobic coatings improved the supercooling degree respect to the reference non-coated case by 7 % to 44 % at 1000 kg/h. The target of 5 kW supercooling power has been reached with two coatings for a mass ow rate of 1000 kg/h in the water cycle. For a mass flow rate of 2000 kg/h a supercooling power of about 6 kW has been reached for five coatings at a temperature of −2.5 °C and hold constantly for a time span of 3 h. Some coatings could reach lower temperatures at this mass flow but the experimental setup was limited to this supercooling power. Thus, the full potential of these supercoolers in terms of capacity is still to be found. The two coatings performing best in the heat exchanger tests were both from the family class hybrid organic-inorganic silane sol-gel (HOIS). Both coatings showed the best results in the small scale laboratory tests as well. From previous investigations it was found that high phosphorous nickel plating creates a beneficial surface to achieve low temperatures. In order to analyse the potential benefits two different types of plate heat exchanger, i.e. brazed and gasketed, were evaluated. Due to the smaller laboratory setup capacity, the heat exchangers were 25 % smaller compared to those tested using icephobic coatings. As reference, the same heat exchangers were tested without any treatment. The nickel layer shows an increase of the supercooling potential of 7 % for a brazed heat exchanger and a water mass flow of 500 kg/h. For a gasketed heat exchanger of similar capacity, little benefits were observed. An average supercooling power of 2.3 kW was achieved on these experiments due to a lower mass flow and heat transfer surface area compared to the heat exchanger prototypes used for the icephobic coatings experiments.

Seasonal energy storage is one of the largest challenges of the energy turnaround. In the project HybridStock, the seasonal storage of renewable energy in aluminium is investigated. At times of high availability of electricity from renewable sources, this energy is converted to chemical energy and stored in elementary aluminium. In winter, chemical energy from the oxidation reaction of aluminium is used to produce heat and electricity. In this project the concept which was the subject of the feasibility study HePoStAl is further pursued through laboratory work and the construction of prototypes.

La población de España ha crecido en seis millones de personas desde que dio comienzo el siglo XXI, pero ese crecimiento no ha sido homogéneo en todo el territorio: tres de cada cuatro municipios, principalmente rurales, han perdido población durante la última década, fenómeno que también afecta a capitales de provincia situadas en regiones con una población envejecida. Este proceso de despoblación contrasta con el desarrollo de las grandes ciudades españolas, que ven acelerado su crecimiento y refuerzan su papel como polo atractor de inversión. Este informe trata de analizar cómo la situación geográfica y socioeconómica de la Comunidad de Madrid ejerce un poder atractor sobre los recursos de sus provincias limítrofes. Varias de estas provincias muestran indicadores sociodemográficos parecidos y comparten el fenómeno de la despoblación como principal reto para garantizar su desarrollo; situación que ha derivado en un incremento de sus niveles de desigualdad respecto a las grandes ciudades. Agrupadas bajo el concepto de la “España vaciada”, estas zonas han conseguido introducir en el debate público una nueva corriente identitaria, ideológica y social que reclama medidas para frenar esta despoblación y la desigualdad que genera, apostando por nuevos modelos de desarrollo.

The Slurry-HP II project provided the first steps towards the development of a supercooling heat exchanger that can be used as evaporator in heat pumps for solar ice-slurry heating applications. A solar ice-slurry system is a particular case of a solar-ice system with the main difference that no heat exchangers are present in the ice storage when the slurry concept is applied. This is expected to reduce installation cost by approximately 10 %. Although our idea was originated to provide heating demands to residential buildings, the concept of supercooling ice slurry and the methods developed in this project can be applied for residential, commercial and industrial refrigeration, too. The specific objectives of the present project were: i) find the most promising currently available icephobic coatings that could delay ice formation ii) develop a methodology to characterize icephobic coatings for underwater applications and iii) analyse the freezing point depression (degree of supercooling) and its stability as a function of coating, fluid velocity and temperature of the coated surface. Within the project we aimed to find the most promising available icephobic coatings developed for atmospheric conditions and assess them for supercooling applications. Thus, a key question for us was: How will coatings developed for atmospheric conditions perform when immersed in water and submitted to forced convection?To try to answer this question, we developed a methodology to characterize icephobic coatings with the goal to select the best candidates to be used in future supercoolers. During the project another question arose: Are state-of-the-art testing methods for atmospheric conditions enough and reliable to characterize coatings for immersed applications with a fluid in motion?

Treball Final de Màster Universitari en Professor/a d'Educació Secundària Obligatòria i Batxillerat, Formació Professional i Ensenyaments d'Idiomes. Codi SAP129. Curs: 2017/2018 El següent Treball Final de Màster (a partir d’ara TFM) pertany a la modalitat de millora educativa seguint les pautes de la normativa de TFM de la Universitat Jaume I. El treball és centra en l’alumnat de 2n ESO E de l’IES Honori Garcia de la Vall d’ Uixó i pretén, a través d’una proposta de canvi metodològic i activitats relacionades amb recursos TIC fer veure a l’alumnat actual que les classes de Tecnologia tenen una utilitat per al dia a dia, i que a més a més, són interesants. Al llarg del primer període de pràctiques i mitjançant una enquesta de satisfacció, l’observació directa i entrevistes amb el professor actual, s’ha detectat que els alumnes tenen un total desinterès per l’assignatura i tanmateix creuen que no serveix allò que fan al taller per al seu dia a dia. Les pautes seguides en aquest treball corresponen a la metodologia descrita com investigació-acció. Per a portar a terme el pla d’acció s’utilitzaran part de les sessions que componen la unitat didàctica “Electricitat bàsica”. Aquesta unitat està dissenyada a partir dels criteris d’avaluació establerts al currículum segons la normativa de la Comunitat Valenciana. La metodologia proposada es l’anomenada Flipped Classroom. A més a més, també es farà ús en l’aula de les Tecnologies de la Informació i la Comunicació (TIC) com a recurs educatiu. Una vegada finalitzades totes les tasques programades en aquest projecte d’investigació-acció, es pot concloure que la nova metodologia i la nova manera de treballar han sigut ben rebudes pels estudiants, i a més a més, els resultats han sigut completament satisfactoris. Simultàniament, l’objectiu principal s’ha assolit, però no obstant això, després de la reflexió i el tancament del cicle d’investigació-acció han sorgit noves propostes de millora en les quals es deuria començar a treballar, començant per tant un cicle nou.

El presente trabajo tiene por objeto examinar los aspectos tributarios del fenómeno del crowdfunding, nuevo método de financiación alternativo que se encuentra en auge en nuestro país. Esta nueva forma de financiación presenta muchas peculiaridades en el ámbito tributario, pues dependiendo del análisis que se haga de la parte interviniente, y del tipo de crowdfunding, nos situaremos en una figura impositiva u otra, y con una mecánica distinta de tributación.

The combination of solar thermal and heat pump systems with ice storages, the so-called solar-ice systems, are becoming popular in Switzerland for the provision of space heating and domestic hot water. These systems can have a high efficiency, in the range of ground source heat pumps (GSHP) or higher, without being submitted to regulations of ground water protections. However, today's system cost are still higher than those from GSHP and research is needed to make solar-ice systems more efficient and cost competitive. One approach to improve the efficiency and the investment cost of solar-ice systems is to optimize the heat exchanger area in the ice storage. Besides the aims of increasing the efficiency and reducing installation cost, an appropriate heat exchanger design can increase the ice fraction. The aim of the present project is to find suitable heat exchanger types and define the optimum heat exchanger area needed in the ice storage based on energetic and cost indicators. This report is separated into six main chapters. Besides the first (Introduction) and the last (Conclusions) chapters, the report has four main chapters. Experimental results of different heat exchangers, i.e. capillary mats, flat plates and coils are presented in chapter 2. The mathematical description of an ice storage model able to cope with all experimentally analyzed heat exchangers is presented in chapter 3. In chapter 4, results from the validation of the model using the experimental data from chapter 2 are shown. The optimum heat exchanger area for the most promising heat exchangers was evaluated from a system perspective in terms of energetic efficiency and heat generation cost. The energetic simulations of the complete solar-ice system with varying heat exchanger type and area for different collectors areas and storage volumes is presented in chapter 5. In the same chapter, the cost effective heat exchanger area was evaluated and compared with state of the art ground source heat pump systems. The main conclusions of this project can be summarized as follows. Very high ice fraction can be reached with all heat exchangers and the casing did not show any damage under high ice fraction conditions. This means that designing an ice storage able to reach an ice fraction up to 95 % or higher should be safe. Therefore, the size of the ice storage, and thus the cost of the system, have the potential to be reduced. From all the heat exchanger analyzed, the most promising designs for small ice storages (below 5 m3) are polypropylene capillary mats (CM) and flat plates (PF) of stainless steel. From these two heat exchangers, capillary mats showed the best performance considering energetic and cost indicators. Solar-ice systems using ice storages volumes from 0.3 to 0.5 m3 per MWh of yearly heating demand, and selective uncovered collectors with 1.5 to 2.5 m2/MWh in the city of Zurich were able to achieve system performance factors SPF ranging from 3.5 to 6 with both CM and FP in a single family house with 10 MWh of yearly demand. Considering the cost of the system, only simulations with CM were able to achieve lower heat generation cost than that of the GSHP with higher SPF (an SPF of 4 was assumed for GSHP). For example, a system with a collector area of 1.5 m2/MWh and an ice storage volume of 5 m3/MWh, can reach heat generation cost of 29 Rp./kWh, 0.5 Rp./kWh below the GSHP reference cost, with an increase of SPF of 20 % respect to the GSHP system. However, there targets can only be achieved using CM and with the appropriate heat exchanger area. The optimal heat exchanger area was found to be around 5 to 6 m2 per m3 of ice storage for CM and around 10 to 12 m2/m3 for FP. These heat exchanger ratios correspond to a distance between heat exchangers of around 12-17 cm for both CM and FP. These results were obtained assuming a conservative maximum ice fraction of 80 %.

Aquest projecte estudia la problemàtica que es pot trobar la indústria química de Tarragona en el tractament de les aigües residuals depurades, concretament per al compliment de la nova normativa degut a la publicació de la Best Available Techniques (BAT) References Documents (Bref) del Common Waste Water (CWW). Farem un anàlisi de les possibilitats de tractament a partir de la caracterització de l’aigua actual a tractar i els límits que imposa la nova normativa, molt més restrictiva en quant a emissions, analitzant les tècniques disponibles per tal que siguin el màxim d’eficients. Farem un anàlisi per exclusió en funció de la millor idoneïtat en quant a cost econòmic però també en quant a operativitat d’explotació i manteniment davant la possibilitat de fer-se realitat la seva construcció.

Treball Final de Grau en Mestre o Mestra d'Educació Primària. Codi: MP1040. Curs acadèmic 2013-2014

This document covers the definition of reference multi-family buildings and the calculation of the corresponding energy demands to be used in the simulation framework developed in Task 1.3. The study targets two distinct scenarios: space heating (SH) dominated and space cooling (SC) dominated climates, corresponding to Northern/Central and Southern Europe, respectively. As a base for the energy demand calculations, two particular buildings representative of each zone were defined as reference cases. All the parameters, such as dwelling floor surface, insulation, etc. were set considering average values, resulting in the typical kind of construction that can be found in each zone. Additional parameters, such as number of occupants, use of appliances, etc. were also particularized so that the energy consumption is also representative of each case. Both reference cases were modelled using different simulation software. Then, several scenarios were tested in order to calculate the corresponding energy demands in various conditions. Mainly, new low-energy buildings (low space heating/cooling SH/SC demand with a significant share of domestic hot water DHW) and older SH/SC dominant buildings were simulated. The aim was to obtain different sets of conditions to further analyze the performance of the systems developed in the project when implemented in different kinds of buildings. In order to do that, relevant parameters, such as U-values or infiltration rate, were modified in the models to representative values. Reference values according to local regulations were considered when doing so. Additionally, different climatic zones were analyzed for each of the cases, so as to broaden the scope of performance and applicability studies that will be undertaken in other tasks (mainly within WP 7). For instance, the dual-source system, which is intended for Southern Europe, i.e. typically cooling dominant climates, will also need to provide heat (e.g. for the case of Madrid). For the purpose of providing the necessary data to assess such cases, the Southern European reference building was simulated also in a climate in which heating demand is significant: Bilbao. Apart from the heating and cooling demand, domestic hot water (DHW) and electric demands were calculated in order to simulate the complete system with the whole energy demand. Occupant behavior was taken into account in the calculation process. Consequently, the whole energy demand of different reference buildings was obtained for various climates. All the combinations result in energy data representative of a significant number of European buildings. This reference data will be used as an input for the design of the systems developed within the project as well as for the extrapolation to various conditions, maximizing the impact of the project. Finally, the preliminary design conditions were defined for each heat pump concept. These reference design points were defined taking into account the characteristics of each concept as well as nominal conditions derived from applicable standards.

This document covers the definition of reference multi-family buildings and the calculation of the corresponding energy demands to be used in the simulation framework developed in Task 1.3. The study targets two distinct scenarios: space heating (SH) dominated and space cooling (SC) dominated climates, corresponding to Northern/Central and Southern Europe, respectively. As a base for the energy demand calculations, two particular buildings representative of each zone were defined as reference cases. All the parameters, such as dwelling floor surface, insulation, etc. were set considering average values, resulting in the typical kind of construction that can be found in each zone. Additional parameters, such as number of occupants, use of appliances, etc. were also particularized so that the energy consumption is also representative of each case. Both reference cases were modelled using different simulation software. Then, several scenarios were tested in order to calculate the corresponding energy demands in various conditions. Mainly, new low-energy buildings (low space heating/cooling SH/SC demand with a significant share of domestic hot water DHW) and older SH/SC dominant buildings were simulated. The aim was to obtain different sets of conditions to further analyze the performance of the systems developed in the project when implemented in different kinds of buildings. In order to do that, relevant parameters, such as U-values or infiltration rate, were modified in the models to representative values. Reference values according to local regulations were considered when doing so. Additionally, different climatic zones were analyzed for each of the cases, so as to broaden the scope of performance and applicability studies that will be undertaken in other tasks (mainly within WP 7). For instance, the dual-source system, which is intended for Southern Europe, i.e. typically cooling dominant climates, will also need to provide heat (e.g. for the case of Madrid). For the purpose of providing the necessary data to assess such cases, the Southern European reference building was simulated also in a climate in which heating demand is significant: Bilbao. Apart from the heating and cooling demand, domestic hot water (DHW) and electric demands were calculated in order to simulate the complete system with the whole energy demand. Occupant behavior was taken into account in the calculation process. Consequently, the whole energy demand of different reference buildings was obtained for various climates. All the combinations result in energy data representative of a significant number of European buildings. This reference data will be used as an input for the design of the systems developed within the project as well as for the extrapolation to various conditions, maximizing the impact of the project. Finally, the preliminary design conditions were defined for each heat pump concept. These reference design points were defined taking into account the characteristics of each concept as well as nominal conditions derived from applicable standards. &nbsp