Dynamic modeling of thermal and electrical microgrid of multi- apartment in different European locations

In this paper authors investigate the dynamic behaviour of a potential residential microgrid which includes four apartments, a natural gas fuelled m-CHP Stirling engine, a 4 kWp photovoltaic plant, an electrical energy storage consisting of 5.0 kWhe batteries and a natural gas back-up boiler. The thermal and electrical microgrid performance are investigated for three different European locations, namely Brescia, Bruxelles and Oslo. In general, the analysis shows that coupling a m-CHP Stirling engine with a PV plant allows to sensibly extend the self-sufficiency of the microgrid throughout the year. In addition, the use of an electrical energy storage device is of fundamental importance to extend the self-consumption of the electrical energy produced especially in warm and hot seasons. The storage system indeed allows to match the multi-apartment residential consumptions and the renewable production profile. In particular, the electrical energy collected by the PV system during the day-time is partially released during the night-time thus reducing the fossil fuel energy demand. Moreover, the electrical storage system allows to extend the profitability of the Stirling engine operation at nominal load thus increasing the m-CHP efficiency and the self-sufficiency of the microgrid in cold climates. In general, the analysis proves that the developed model can be used as a useful design tool to assess the opportunity of employing alternative energy technologies and different management system strategies for small residential users.