Ground source heat pump carbon emissions and primary energy reduction potential for heating in buildings in Europe—results of a case study in Portugal

The main purpose of this study is to assess the impacts in the European Union (EU) of a fuel switching strategy focused on the replacement of Natural Gas (NG) boilers by high efficiency Heat Pumps (HPs) supplied by electricity with a fast decreasing carbon content. Additionally, to illustrate the high performance of heat pumps, the experimental results of an advanced Ground Source Heat Pump (GSHP) system installed in a service building in Portugal are presented.Based on the analysis carried out, it was found that the large scale use of heat pumps for space heating in buildings can contribute to significant primary energy and CO2 emissions savings, when compared to NG boilers. In Europe, in 2050, through the replacement NG space heating in buildings by high efficiency heat pumps, around 60% of the primary energy required and 90% of the associated CO2 emissions can be saved. At global EU level, in 2050 the European NG dependency on external suppliers can be decreased to 50% and an additional contribution of 5.6% for Renewable Energy Sources (RES) share in the total final energy consumption can be achieved.Furthermore, HPs can also play an important role towards exploiting the increasing penetration of renewable electricity generation, effectively contributing to the replacement of fossil fuels and in particular to decrease the growing natural gas dependency of Europe from risky and unstable countries.