Heat pumps
Heat pumps
The technology, when it suits, when it doesn't — including the cold-weather question and what makes a UK install actually perform.
Reading order — beginner first
What is a heat pump?
A heat pump is a fridge running backwards. Instead of moving heat out of a small box, it moves heat into your home from the air or ground outside. It uses electricity to do the work, but for every 1 kWh of electricity it uses, it delivers 3–4 kWh of heat — which is why it can heat your home for less than a gas boiler does, even with electricity costing more per kWh than gas.
Do heat pumps work in cold weather?
Yes. Modern UK air-source heat pumps are tested to operate at -20°C and remain efficient down to about -10°C in real-world use — well below typical UK winter lows. Norway, where winter temperatures regularly drop below -20°C, has heat pumps in 6 of every 10 homes. The 'heat pumps don't work in winter' claim is one of the most persistent UK retrofit myths, and it's wrong.
Will a heat pump work in my old British home?
Often, yes — but the order matters. Solid-wall pre-1919 homes typically need fabric work first; 1930s cavity homes usually want cavity fill and a loft top-up before sizing the heat pump; better-fabric post-1960 stock can often go ahead with the heat pump first. 'Old' alone doesn't disqualify; uninsulated does.
Heat pump running costs vs gas — the honest numbers
On the right tariff and with a properly installed system, a heat pump typically saves £100–£200/year vs the same home on gas. On a standard tariff with a poor install, you can pay more. Tariff choice, install quality, and home fabric together account for the variance — not the technology itself.
The Boiler Upgrade Scheme explained
The Boiler Upgrade Scheme is a £7,500 government grant toward an air-source heat pump install in England and Wales. Your installer applies on your behalf and the grant comes off your invoice — not refunded later. As of late 2025, around 86% of applications are approved.