Heat pump in a park home
Usually off the gas grid and running on LPG or oil, which are far more expensive per unit than mains gas. That completely changes the comparison — a heat pump often wins comfortably.
With the radiators as they are
Saves £61
a year · existing radiators, on the small side
With upgraded radiators
Saves £247
a year · SCOP 3.4
What to do first
Being off the gas grid also means you may qualify for the larger grant. Worth checking before that window closes.
Upgrading the radiators is worth about £186 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 9,000 kWh a year.
- That is roughly 6,750 kWh of actual heat, once boiler losses are taken off.
- A heat pump on the existing radiators would use about 2,700 kWh of electricity to deliver it.
- Break-even electricity price: 28.36p 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.