The short answer
For a typical home in Attica, a heat pump costs roughly a third as much to run as an oil boiler for the same warmth. The purchase cost is higher, but the difference is usually paid back within a few years, and faster still if you have solar panels.
What a winter costs
Take a 120 m² detached house that needs about 12,000 kWh of heat a year.
Assumptions used in the examples: electricity price 0.16 €/kWh, surplus payment 0.06 €/kWh, heating oil 1.15 €/litre, Athens. Figures are indicative. Our study works out your own numbers.
Why the difference is so big
A boiler burns fuel and, at best, delivers slightly less heat than the energy the fuel contains. A heat pump burns nothing: it moves heat from the outside air into your home. For every 1 kWh of electricity it delivers 3 to 5 kWh of heat.
Will it work with my existing radiators?
In most cases, yes. R290 heat pumps deliver water at up to 75 °C, so they also work with conventional radiators. Efficiency is better with underfloor heating or fan coils, which need a lower water temperature. In our study we check whether your radiators are sufficient.
What happens when it gets very cold?
Modern heat pumps keep heating even at −25 °C. Efficiency drops as the temperature falls, which is why we size them for the cold days in your area. In Attica such days are few.
When it pays to switch now
- Your boiler is more than 15 years old or needs a major repair.
- You also want cooling in summer from the same system.
- You have solar panels or are thinking of getting them.
- You are renovating or replacing your radiators.
Maintenance
A heat pump has no chimney, burner or tank. It needs one annual check: cleaning the coil and filters, and checking pressures and settings. An oil boiler needs its burner cleaned and adjusted every year, plus fuel orders.