Heat pumps integrated with photovoltaic systems as a basic solution for new housing estates during the energy transformation in Poland
The paper considers the possibility of using heat pumps integrated with photovoltaic systems as a basic solution for energy systems in new housing estates on the outskirts of Polish cities. The necessity of energy transformation in countries such as Poland, which for years were dominated by a centralized energy economy based on coal, was emphasized. One of the possible energy-efficient and environmentally clean ways is to implement the idea of creating districts based on renewable energy. As the analyses showed, in Polish conditions it is most advisable to use solar energy to gain heat, as well as to generate electricity to cover the demand for electricity to home receivers and to drive heat pumps. It is possible to send the energy generated on site (photovoltaic) to the grid, as well as to take electricity from the grid, when needed. Two basic configurations of heating systems with ground heat pumps were considered. In the first one, each building of the hypothetical housing estate is equipped with its own heating installation with a heat pump associated with its own individual photovoltaic system. In the second configuration, a small heating plant with several heat pumps that can operate individually or in parallel, with several central heat tanks, was considered. Heat pumps and auxiliary devices are powered by the photovoltaic systems. In the first configuration, a photovoltaic selfenergy consumption index of 25% was obtained, in the second at 45%. The self-energy consumption index is the share of PV generation that is directly consumed on site. The high index is recommended, due to cooperation with the network, which should not be overloaded of renewable energy in the same time. In the considerations, electricity storage was not taken into account, only heat storage and matching heat use to electricity generation.