This is the combination the whole site points towards, so it is worth being precise about why, and about where it does not work as neatly as it sounds.
The argument in short
A heat pump makes solar more valuable, and solar makes a heat pump cheaper to run. Each fixes the other’s main weakness.
Solar’s weakness in the UK is that a typical household exports a large share of what it generates, for roughly half what it would save by using it. Heating is also the biggest part of most households’ energy bill and solar does not touch it, because that bill is gas.
A heat pump’s weakness is that it runs on electricity, which costs about three and a third times as much as gas per unit, so at current prices a typical installation only breaks even on running cost. See running costs.
Put them together and both problems get smaller.
Why solar helps the heat pump
A heat pump is a large electrical load that runs for much of the year. Every unit of electricity it takes from your own panels instead of from the grid costs you nothing at the point of use, rather than 26.32p.
That directly lowers the effective electricity price the heat pump runs on, which is the number that decides whether it beats a gas boiler.
Why the heat pump helps the solar
A heat pump raises your self-consumption, the share of your generation you use at home rather than exporting. Self-consumption is the single biggest factor in whether solar pays for itself. See payback.
Adding a heat pump to a house that already has solar makes the existing panels work harder without spending another penny on them.
The seasonal problem, stated honestly
Here is the part that gets glossed over.
Solar produces most in summer. A heat pump uses most in winter. In December and January, when your heating demand peaks, a UK solar system produces very little.
So solar does not directly power your heating on the coldest days. Anyone suggesting otherwise is overselling it.
What solar does do across the year:
- Covers hot water for a large part of the year. Hot water demand is reasonably steady and daytime solar handles a good deal of it from spring to autumn.
- Covers shoulder-season heating. March, April, September and October, when heating runs intermittently and there is decent daylight, are genuinely well matched.
- Raises overall self-consumption, because the heat pump adds load through much of the year, not just at peak.
- Offsets the rest of the house’s electricity, freeing more of your budget.
The combination is strong over a year. It is not strong on a January evening. Being clear about that is the difference between a household that is pleased with the system and one that feels misled.
Where the battery fits
A battery makes the combination work better, for a reason that has nothing to do with solar.
On a time-of-use tariff, a battery charges overnight at a low rate and runs the house, including the heat pump, through the expensive evening period. That works in December, when the panels do not. It is the piece that covers the seasonal gap above.
See smart tariffs and solar batteries.
What the combination costs
| Solar, 4kW | £6,600 to £8,400 |
| Air source heat pump, after the £7,500 grant | £4,000 to £8,000 |
| Battery, 4 to 5kWh | £3,500 to £5,500 |
All currently zero-rated for VAT until 31 Mar 2027.
Indicative ranges, last reviewed 6 Nov 2026.
Practical points if you are doing both
Do the heat loss calculation first It tells you the size of heat pump, which tells you the electrical load, which informs the solar and battery sizing. Doing it the other way round leads to a system that does not match.
Check your main fuse and consumer unit once A heat pump, solar, a battery and possibly a car charger together can push a property towards a supply upgrade. Find out at the start.
Mind the grid connection limit Solar plus a battery that can export counts towards the same threshold. See grid connection.
Think about whether you are keeping gas Removing the gas connection entirely saves the standing charge every day. Keeping it for a hob means you keep paying it. It is a bigger decision than it looks.
Sequence matters less than you think, except for the roof. If your roof needs work, do that first. Otherwise either order is fine, though doing both together saves on scaffolding and electrical work if the same firm handles them.
They are often different installers Few firms do both well. That is not a problem, but make sure each knows what the other is doing, particularly about the consumer unit and the electrical capacity.