Duncan GibbNew paper shows heat pumps suitable for all European countries - even cold ones!
Research out today by myself, @janrosenow and @richardlowes at @RegulatoryAssistanceProject with Neil Hewitt.
We collected real-world data across 3 continents. đ§”
Our research looked at field testing of around 550 heat pumps with more than 2760 measurements.
These data showed the coefficient of performance (COP) â basically, how well a device transforms one unit of energy into useful heat â related to the average outside temperature.
The key finding is that COP does, of course, decline as outside temperature decreases. But it remains high.
Even on the coldest winter days, a standard air-source heat pump can still operate with a COP around 2.
Or, twice as efficiently as a boiler or electrical heater.
Standard heat pumps heat efficiently during winters where temperatures rarely fall below -10°C.
As most European countries experience milder winters, our analysis suggests that heat pumps can work in these conditions without concerns about efficiency or back-up heating.
I'm excited about this research because I hope it helps put to rest the claim that heat pumps don't work in the cold. They do.
With a suitable device selected (e.g. cold-climate or not), proper sizing, and high-quality installation, they can provide efficient winter heat.
So when is back-up heating actually needed?
Our view is that in climates where the temperatures rarely fall below -10°C, standard heat pumps can comfortably provide full heating.
Below these conditions, a standard heat pump can still provide almost all the heating load.
But on the coldest days, either a cold-climate heat pump may be appropriate, or some form of back-up heating to boost the heat pump such as a pellet boiler or green gas boiler.
Also, ground-source heat pumps are an important technology for the coldest climates.
Finally: these data only show high efficiency. What about comfort?
In one of the US studies, 32 of the 42 cases reported being âvery satisfiedâ with their heat pump in the past year. 10 respondents noted âimproved comfort and temperature maintenanceâ.
https://e4thefuture.org/deep-dive-research-heat-pump-building-electrification/
An unrelated project surveyed 710 homeowners who recently installed a heat pump: comfort improved in 81% of cases and decreased only in 1%.
Ten to twenty households were interviewed in 22 countries: 20 EU member states and Norway and UK.
https://www.coolproducts.eu/wp-content/uploads/2022/02/EEB-Heat-Pump-Comfort-Audit-Report.pdf
There is no convincing technical reason why heat pumps cannot be widely used in all European climates.
And their potential may even be greater than previously assumed by their biggest fans. (Dad pun intended)