Rigorous assessment of low GWP refrigerants in heat pumps from an ecologic perspective using life cycle assessment.

Enhancing the significance of global warming and systematically reducing greenhouse gas emissions can be established by utilizing transparent assessment methodologies. Within this work, we contribute to the estimation of carbon dioxide equivalent emission impact of different refrigerants for direct and indirect emissions. Regarding heat pump heating systems in dynamic heat supply systems for a whole lifecycle, comparable boundary conditions are chosen. Direct emissions correlate to the static GWP value of a refrigerant and the refrigerant charge of the heat pump. Indirect emissions occur in the production, distribution, operation and disposal of the heat pump with special respect to the refrigerant. This approach allows a direct comparison of the impact of low GWP refrigerants on lifecycle carbon dioxide equivalent emissions. We state that, if we do not reduce indirect emissions by increasing efficiency or obtaining PV electricity, the GWP of the chosen refrigerant is rather irrelevant.