The potential for CO2 heat pumps in the South African industrial sector

Up to now, heat pumps have mainly been used in the commercial and residential sector, with limited application in the industrial sector. This paper discuss the potential in the industrial sector for high temperature heat pumps using CO2 as working fluid. These heat pumps have an operating range of up to 130 degrees C. An overview is given of the energy profile of South Africa, highlighting the largest energy users in each sector. It was found that the industrial sector has the largest energy use, thus having the largest potential for energy savings. An investigation was done to determine what the industrial demand for process heat and which common industrial processes can be heated by CO2 heat pumps. It was found that CO2 heat pumps can accommodate 33% of the common industrial processes heat applications in totality and 51 % partly. Finally, three international case studies of CO2 heat pumps are discussed showing the potential savings obtainable. From these studies it was found that although CO2 heat pumps have a relative high Coefficient of Performance (COP) and save up to 30% of the CO2 emissions, the straight payback may still be long due to the units not being mass produced at this point in time.