Since 2015, district heating schemes in Denmark have installed Heat Pumps with total capacities exceeding 1000 MW. The majority are based on air-source technology. Much experience has been harvested, and consequently, consultants and end-users are currently changing their specifications and evaluation models for new Heat Pump projects.

COP (Coefficient of Performance) is still important, but several other factors are equally important. The key word is FLEXIBILITY regarding temperatures and fast start and stop capabilities. Additionally, efficient and functional defrost algorithms, along with robustness, are crucial. Until 2020, most Heat Pump installations used R-717 as the refrigerant, but since then, R-744 Heat Pumps have gained significant market shares, with capacities u ...