Comparative study of indirect photovoltaic thermal solar-assisted heat pump systems for industrial applications

In this paper, a comparative study of indirect photovoltaic thermal solar-assisted heat pump systems for water heating in industry is presented. The solutions to achieve a system with a steam ejector heat pump and a system with a mechanical compression heat pump integrated in a paper mill are proposed. The mathematical models are developed and used to evaluate the performance of these systems for the Bacau, Romania climatic conditions. A numerical study highlights the energy, exergy and economic efficiency of each system for the different operating hot water temperatures supplied. The obtained results show that an increase in the hot water temperature leads to a decrease in the energy, exergy and economic performance and that in an industrial company with continuous operation, the best solution is a photovoltaic thermal system with a steam ejector heat pump.