Simulation of solar energy use for building heating by a vapor compression heat pump

Abstract

This article reports the investigations of a building heating by a vapor compression heat pump that is entirely powered by solar energy. The building has the space heating system, the heat generation system, and the electricity generation system. The space heating system comprises floor heaters. The heat generation system comprises a water-to-water heat pump, and a ground heat exchanger. The electricity generation system comprises the photovoltaic (PV) system. The PV system generates electricity that either may drive the compressor of the heat pump or may feed-in the electricity grid. A simulation is carried out by using EnergyPlus software with additional theoretical approach. Two cases are investigated for a design of the PV system. In case A, the electricity distribution network is used for electricity storage. The PV system would yearly produce the exact amount of electricity that the compressor needs. The case B refers to design of the PV system that would produce the exact amount of electricity that the compressor needs in the month with its highest electricity consumption. Then, the PV system would directly satisfy all compressor needs for electrical energy during all other months of year, and rest of electricity would be feed-in to the electricity grid. The article reports the area needed for the PV panels for these two cases. For the both cases, this article will also report the payback time as a function of the feed-in tariff of generated electricity. It is found that the feed-in tariffs for the generation of electricity in Serbia are not large enough and should be corrected if the electricity production from solar energy will be promoted.