Photovoltaic thermal hybrid solar collector and district heating configurations for a Central European multi-family house

Highlights: • PVT systems in Central Europe are an effective path towards zero carbon buildings. • They can contribute notably to enhancing sustainability and energy security. • Their profitability and success will depend on the right policies and regulations. • The consumer right to export energy to the network is vital for this success. - Abstract: In central European countries, district heating is a common and standard way to cover the residential heat demand. While the consumers are connected to the heat network and electricity grid, they are being increasingly encouraged to become prosumers by having own distributed renewable energy generation. At the same time, the energy performance requirements for new and renovated buildings are setting progressively higher energy efficiency standards. This tendency is effectively reducing the carbon footprint of the residential sector in Central Europe and will eventually lead to low and zero carbon buildings becoming the standard. One of the emerging technologies within this approach are Photovoltaic thermal hybrid solar collectors, which combine heat and power generation and are easy to integrate in buildings. In this study, the possibility to use such a system, supported by a heat pump, in a Central European multi-family house is addressed. Three configurations are considered; the building, the hybrid and district heating configuration. In the building configuration the heat from the solar collectors is used directly for domestic hot water and space heating and no use is made of excess heat. In the hybrid configuration, the direct heat consumption in the building is prioritized, while excess heat is exported to the district heating network. Finally, in the district heating configuration, the solar system operates as a micro-plant that supplies all produced heat to the district heating network. The study shows that the use of Photovoltaic thermal hybrid solar collectors in combination with district heating provides important benefits in terms of sustainability, energy security, carbon abatement and costs. Thereby, configurations that can export heat to the network have better energy efficiency and result more profitable.