Heat pump COP, part 1: Generalized method for screening of system integration potentials

Industrial heat pumps (IHP) are major contributors to the transformation towards a future energy system based on electrical power. The main barrier for IHP integration is the operating cost and thereby the COP. COP is highly dependent on the temperature difference between the source and the sink. Even in the first evaluation of IHP integration, a fairly correct COP is needed. Today, an estimation of the expected COP is often done by IHP suppliers, and it involves detailed choices such as working fluid, compressor technology, and configuration. This paper (part 1) presents a simple, generic, and generalized method based on the theoretical maximum COP of the Carnot or Lorenz process. It does not involve any technological choices. Based on the model, the first system integration assessment including economic analysis can be done. This is often an iterative process of choosing temperature levels and heating capacity. The use of the model is demonstrated and the general conclusions are presented. In part 2, the method is extended to account for real process parameters such as working fluid, and compressor and heat exchanger characteristics.