Industrial heat pump for high temperature district heating

Abstract

Domestic heat pumps for shallow geothermal heating of family houses are popular and the range and supply of standard solutions is large. However, in applications for large capacities and temperatures, like district heating in the mega Watt range, standard solutions for high temperatures are scarce and usually not suitable off-the-shelf, which demands customized industrial heat pumps to be designed to fit the specific application. At the Brædstrup CHP plant in Denmark, a pilot project deployed in 2012, is being tested involving a seasonal thermal energy storage system in underground boreholes, charged by excess thermal energy from thermal solar panels. An industrial heat pump system using the natural refrigerant ammonia, is extracting the thermal energy from the storage when needed, and produce hot water at 85°C, for the district heating grid. The heat pump also acts as contributor to electricity grid peak shaving during high wind power and photo voltaic production periods