Summary: |
Buildings are responsible for a large portion of the energy consumption and harmful emissions to the environment. To change this situation, several countries including the EU are proposing regulations to reduce the primary energy consumption of buildings. The coming European Performance of Buildings Directive (EPBD2 [1]) will require that new buildings have to be nearly Zero Energy Buildings (ZEBs) by 2018/20. Achieving this goal implies a large use of renewables on-site combined with energy saving measures.
Solar energy systems are now widely used, either to generate electricity on-site, through the use of photovoltaic (PV) collectors, either to supply useful heat, mostly in domestic hot water applications, using solar thermal (ST) collectors. It is however possible to obtain useful space heating and cooling with solar thermal systems, eventually combined with heat pumps. Therefore, solar energy (both PV and ST) can be used with a combination of existing technologies to supply electricity, heating and cooling needs. When combined with adequate storage systems, to compensate fluctuations in solar energy supply, these renewable energy systems may supply a large part of, or even all, the energy needs of a building, without environmental impact. They would decisively contribute to the ZEB target.
The proposed research aims to develop a reliable and cost-effective polygeneration system for an existing test building, able to provide electricity, cooling and heating needs. The system will use solar energy as main source, through PV and ST collectors. It will also include different types of storage (electrical and thermal). PV collectors will generate the required electricity needs, using a novel vanadium redox battery pack to overcome mismatches between generation and consumption. ST collectors and a heat storage will supply heating needs through the delivery of hot water, and will supply cooling needs when coupled to a novel variable geometry ejector (VGE) heat pump  |
Summary
Buildings are responsible for a large portion of the energy consumption and harmful emissions to the environment. To change this situation, several countries including the EU are proposing regulations to reduce the primary energy consumption of buildings. The coming European Performance of Buildings Directive (EPBD2 [1]) will require that new buildings have to be nearly Zero Energy Buildings (ZEBs) by 2018/20. Achieving this goal implies a large use of renewables on-site combined with energy saving measures.
Solar energy systems are now widely used, either to generate electricity on-site, through the use of photovoltaic (PV) collectors, either to supply useful heat, mostly in domestic hot water applications, using solar thermal (ST) collectors. It is however possible to obtain useful space heating and cooling with solar thermal systems, eventually combined with heat pumps. Therefore, solar energy (both PV and ST) can be used with a combination of existing technologies to supply electricity, heating and cooling needs. When combined with adequate storage systems, to compensate fluctuations in solar energy supply, these renewable energy systems may supply a large part of, or even all, the energy needs of a building, without environmental impact. They would decisively contribute to the ZEB target.
The proposed research aims to develop a reliable and cost-effective polygeneration system for an existing test building, able to provide electricity, cooling and heating needs. The system will use solar energy as main source, through PV and ST collectors. It will also include different types of storage (electrical and thermal). PV collectors will generate the required electricity needs, using a novel vanadium redox battery pack to overcome mismatches between generation and consumption. ST collectors and a heat storage will supply heating needs through the delivery of hot water, and will supply cooling needs when coupled to a novel variable geometry ejector (VGE) heat pump, which has been developed in the last few years by the team members [2]. The use of phase change materials for heat storage will also be investigated. Therefore, the system has the potential to generate all the energy needs of a building, achieving a Zero Energy Building. Robust and reliable control mechanisms for the efficient operation of the ZEB building will be developed.
The target values for peak cooling, heating and electrical power will be 2 kW, 7 kW and 1 kW, respectively. As a result, a cost-effective system prototype and a demonstration site will be built for the first time in Portugal.
The proposed project and the POLYSOL system will strongly contribute to important societal challenges related to efficient and sustainable use of natural resources. The proposed work will also contribute to the priority domains of the national R&D strategy by addressing the use of renewable energies, efficient use of energy (in particular in buildings) and reduction of CO2 emissions. |