Abstract
Low-temperature solar thermal facilities face challenges like large storage systems and solar intermittence. This drives the development of novel storage systems that also implies lower costs. This study proposes the coupling of a low-temperature solar storage system that feeds heat of vaporisation to a heat pump; the pump, at the same time, produces higher temperature thermal energy. The heat pump let to supply heat to low and medium temperature industrial processes in a way that volumetric requirements decrease, compared against using a conventional solar thermal storage system. Using the coolant trans-1,3,3,3-tetrafluoroprop-1-ene like working fluid in the heat pump, it is possible to obtain storage volumes up 30 m3 to supply 4,400 kWh of heat process. This contributes to decrease in 44 % the volume of a conventional storage system. Reducing the installation surface, in turn reduces the costs and the solar thermal systems payback time. These achievements, overall, enable to reach a feasible system that is competitive in front of the fossil fuels costs, reducing or eliminating the environment impact of burning fossil fuels.
