Heat pump in a bungalow
All the floor area sits under the roof, so loft insulation matters more here than in any other house type. Also usually easy to run new pipework and site an outdoor unit.
With the radiators as they are
Saves £67
a year · existing radiators, average size
With upgraded radiators
Saves £202
a year · SCOP 3.4
What to do first
Get the loft to 300mm before anything else. Bungalows also tend to have the easiest, cheapest heat pump installations.
Upgrading the radiators is worth about £135 a year in this house — which is the difference between a heat pump being a good idea and a questionable one.
The numbers behind that
- Typical gas use for this kind of house: about 12,000 kWh a year.
- That is roughly 10,200 kWh of actual heat, once boiler losses are taken off.
- A heat pump on the existing radiators would use about 3,517 kWh of electricity to deliver it.
- Break-even electricity price: 28.02p per kWh. The cap is currently 26.11p.
If your break-even price is above the price you actually pay, the heat pump wins. If it is below, it does not — and no amount of enthusiasm changes that arithmetic. A dedicated heat pump tariff can move your real price down enough to flip it.