Low GWP HFO Refrigerants for residential Heat Pumps to enable a safe and sustainable European building renovation

A reduction of residential buildings’ energy consumption and the electrification of heating are clear objectives of European energy policies.
Heat Pump technology is recognized as one of the main possible replacement for fossil fuel boilers and, due to higher energy efficiency and the use of electricity, can be key to reduce primary energy consumption and to enhance the electrification process. The most common refrigerant employed in Heat Pumps in the past decade has been R-410A. The use of this HFC refrigerant with global warming potential (GWP) of 2088 will be progressively limited to comply with the F-Gas Regulation EU No 517/2014 and Low GWP alternatives, such as HFO blends refrigerants, will be increasingly adopted.

In this study a theoretical comparison between different available Low GWP refrigerants, such as R-454B and R-454C, has been performed. A residential Heat Pump model has been developed to evaluate energy efficiency, energy consumption and total equivalent CO2 emissions in typical European heating season climatic conditions. Extended water outlet temperature range has been considered in order to allow retro-compatibility with existing heating systems. HFO Low GWP refrigerants R-454B and R-454C appear to be the most efficient and low emission solution for new or recent buildings with radiant floor heating and renovation of buildings with radiators, while also fulfilling long term requirements of the F-Gas Regulation EU No 517/2014 and the European Green Deal principles and objectives.