07 May 2025

Beyond Climate Change: Sustainability Assessment of Heat Pumps and Refrigerants

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Replacing boilers with heat pumps significantly reduces greenhouse gas (GHG) emissions, thus rendering them a vital component for the energy transition. The F-Gas and REACH regulations further support GHG reductions by limiting high global warming potential refrigerants. However, heat pumps may shift burdens to other environmental categories beyond climate change, risking overall sustainability in the long term. This study employs a life cycle assessment to evaluate the environmental performance of a heat pump using seven different refrigerants. The findings show that R290 and R717 achieve higher seasonal coefficients of performance (SCOP 3.83-3.88) than, e.g., R1234yf (3.36), reducing indirect emissions in 9 analyzed impact categories by 10-16% through lower electricity demand. As a next step, the integration of circular strategies and the compressor’s lubricant into the assessment is recommended due to its interaction with efficiency in the compressor, its impact on the compressor envelope, and heat pump life-time.