A new study has found that heat pumps are twice as efficient as fossil fuel heating, even at lower temperatures, highlighting their significance in reducing dependence on fossil fuels.
Heat pumps can be multiple times more efficient than oil, gas, or electric heating, according to the study, conducted by the University of Oxford and the Regulatory Assistance Project.
The authors of the study, published in the journal Joule, note that heat pumps have become a crucial technology in the transition to a clean and reliable energy supply and are pivotal for the future of heating.
The analysis demonstrated high performance even at low temperatures. The authors noted that heat pumps operate two to three times more efficiently than combustion heating or electric resistance heating technology.
Heat pumps operate two to three times more efficiently than combustion or electric heating
Heat pumps harness energy from nature and exploit temperature differences. Energy sources for heating include the ground, groundwater, or the external air.
The primary indicator of heat pump efficiency is the Coefficient of Performance (COP) – the ratio of input energy to heat output. The higher the COP, the more efficient the heat pump.
An average COP of 3 to 4 is common for household applications. It means that 3 to 4 units of heat are created from each unit of electricity used. Heat pumps utilizing groundwater have the highest COP, followed by those using the ground source and the air source.
Heat pumps are sufficient for heating in moderate climate
The authors analyzed data from seven field performance studies of air-source heat pumps in a moderate climate, where the average January temperature is above minus 10 degrees Celsius.
Between 5 and minus 10 degrees Celsius, the COP was 2.74, meaning that heat pumps have significantly higher efficiency than fossil fuel and electric heating systems, according to the authors.
The study concluded that even air-source heat pumps, which are the easiest to install, are suitable for temperatures below freezing.
Study demonstrates heat pumps’ efficiency in extremely cold climates
The study demonstrated the efficiency of heat pumps in extremely cold climates, showing they are twice as efficient as electric heating systems.
In extremely cold climates heat pumps are twice as efficient as electric heating systems
Efficiency does decline in extremely cold conditions. However, the authors note that heat pumps can be a backup heating option. The results show that a COP between 1.5 and 2 can be achieved even at extremely low temperatures, such as minus 30 degrees Celsius.
Heat pumps utilize stable and consistent ground temperatures throughout the year, providing a high level of efficiency in cold conditions, the authors explained.
In Europe, colder countries have been using them for decades. In 2021, Norway had slightly over 60 heat pumps per 100 households, followed by Sweden and Finland (with around 45 each) and Estonia (35).
In 2021, Norway had over 60 heat pumps per 100 households
The authors also point out that about 80% of European households are in countries where average January temperatures do not fall below zero. They also emphasize that the broader adoption of air-source heat pumps is a realistic option for decarbonization.