Comparative study of polygeneration systems for commercial buildings

Abstract: In recent times the problems regarding global warming and climate change have become increasingly relevant in our society. Public attention is growing due to seemingly larger and more severe natural disasters each year and the search for solutions to these problems is greater than ever. Humanity is facing a lot of environmental challenges, but one could argue that the increasing rate of greenhouse gas emissions related to energy production and use is the main focus. This study focuses on how electricity generating and storage technologies can be installed for different types of buildings and businesses to maximize economic benefits and at the same time reduce dependency on grid bought electricity. The buildings in the analysis will have prior solar PV systems installed ranging from 35 kW to 254.8 kW in capacity. Three different buildings within this interval have been chosen and have the solar PV capacity of 35.84 kW, 143.36 kW and 254.8 kW. These buildings have been chosen to get three different load profiles that are as different as possible, given the available data. The study concludes that only using solar PV is the financially most profitable system configuration for all three buildings, rated by maximum IRR. Both wind power and batteries have a negative impact on IRR for all buildings. The building with the least changes in day-to-day peak demand benefited the most from solar PV. Wind power affects the demand in a similar way as solar PV, however batteries added more value to a building with a less consistent load curve.