Can I run a heat pump on solar panels?

Yes, and it's one of the best combinations going. The solar panels generate electricity during the day, the heat pump uses electricity to heat your home. Put them together and you're heating your house for free during daylight hours. Add a battery and you extend that into the evening.

Is a heat pump worth it if I already have solar?

Almost certainly. Your solar panels are already generating cheap electricity. A heat pump uses that electricity three to four times more efficiently than a direct electric heater. So your existing solar investment works harder. The BUS grant of £7,500 makes the addition very affordable.

Do I need to upgrade my radiators for a heat pump?

Not always. Heat pumps run at lower temperatures than gas boilers, so undersized radiators can struggle. But many homes, especially those built after the 1980s, already have radiators large enough. Your installer will do a heat loss calculation and tell you which, if any, need swapping. Budget £1,500 to £3,000 if several need replacing.

Will solar panels work on my east or west-facing roof?

Yes. East and west-facing panels generate about 80% of what a south-facing system produces. Still a solid investment. North-facing is the only orientation most installers advise against.

What happens to the BUS grant if I wait?

The Boiler Upgrade Scheme currently runs until at least March 2028, per GOV.UK. But grant schemes get revised, reduced or closed all the time. If you're eligible now and your boiler needs replacing in the next few years, claiming sooner rather than later removes the risk of the scheme changing.

Solar Panels vs Heat Pumps: Which First?

Solar Panels vs Heat Pumps: Which First? | Eco Home Check

You've got £10,000 to spend on making your home greener. Do you put it on the roof or next to the back door?

That's the real question behind every "solar vs heat pump" search. See our guide on 4kW solar panel system costs for more detail. See our guide on heat pump water heaters for more detail. See our guide on how many solar panels you need for more detail. See our guide on energy efficient windows for more detail. See our guide on installing solar yourself for more detail. And for most three-bed semis still running a gas boiler, a heat pump makes more financial sense. The BUS grant knocks £7,500 off the price, the annual savings are higher, and you're replacing the thing that accounts for 60% to 70% of your energy bill. Solar is the better investment for homes that have already sorted their heating, or where the roof is perfect and the budget is tight.

Here's the full breakdown, starting with the bit everyone actually cares about.

Which One Saves More Money?

This is the longest section because it's the one that matters most.

£6,500. That's a typical 4kW solar system after the 0% VAT relief, based on MCS installer data and the Energy Saving Trust. An air source heat pump costs £10,000 to £15,000 before grants, but the Boiler Upgrade Scheme takes £7,500 off, bringing a typical install down to £4,500 to £8,000. So the upfront cost is roughly similar once the grant lands.

The savings picture is where they split.

Solar panels save the average UK household £500 to £700 a year on electricity, according to the Energy Saving Trust. That's a combination of using your own electricity instead of buying it from the grid, plus Smart Export Guarantee payments for the surplus. Octopus pays 15p per kWh exported. British Gas pays 12p. The exact figure depends on how much you're home during the day to use the electricity directly.

A heat pump replacing a gas boiler saves roughly £400 to £600 a year on heating, based on Ofgem price cap rates and Energy Saving Trust modelling. Replace oil or LPG instead and the savings jump to £800 to £1,400 a year because those fuels cost so much more per unit.

But here's what most comparison articles miss. Heating is the bigger share of your energy bill. Gas, oil or LPG for your boiler typically accounts for 60% to 70% of what you spend on energy, per Ofgem household data. Electricity is the other 30% to 40%. A heat pump attacks the bigger number. Solar attacks the smaller one.

So even though the raw annual saving looks similar, the heat pump is cutting into a larger chunk of your bill, and it does it all year round. Solar generation drops in winter, right when your energy bills peak.

The Payback Maths

	Solar (4kW)	Heat Pump (ASHP)
Typical cost after grants/VAT	£5,500–£8,000	£4,500–£8,000
Annual saving (vs gas boiler)	£500–£700	£400–£600
Annual saving (vs oil/LPG)	£500–£700	£800–£1,400
Payback (vs gas)	8–12 years	8–14 years
Payback (vs oil/LPG)	8–12 years	4–7 years
System lifespan	25–30 years	20–25 years
Best for	Homes with good roofs and daytime usage	Homes replacing expensive heating

Costs based on MCS installer data and Energy Saving Trust figures. Heat pump costs assume BUS grant of £7,500 applied. Solar costs reflect 0% VAT.

If you're on oil or LPG, the heat pump wins on payback by a wide margin. If you're on mains gas, payback is similar for both, but the heat pump still edges ahead because it future-proofs your heating against rising gas prices and the eventual gas boiler ban.

One more thing. Solar payback depends heavily on self-consumption. If you work from home and run the dishwasher at midday, you'll use more of your own electricity and save more. If the house is empty all day, you're exporting most of it at 12p to 15p per kWh instead of offsetting grid electricity at 24p. That gap matters.

Which One Gets Better Grants?

Heat pumps. Not close.

The Boiler Upgrade Scheme gives you up to £7,500 towards an air source heat pump and up to £7,500 for ground source, per GOV.UK. Your MCS-certified installer applies for the voucher on your behalf. The scheme runs through to 2030 under the Warm Homes Plan.

Solar panels don't have an equivalent grant for most homeowners. What you get is 0% VAT on residential installations until 31 March 2027, per GOV.UK. That saves £1,000 to £1,500 on a typical system. Helpful, but it's not a £7,500 voucher.

The exception is ECO4. If your household receives benefits like Universal Credit or Pension Credit and your home has an EPC rating of D or below, ECO4 can fund a full solar installation at zero cost. About a third of UK households meet the income criteria, per GOV.UK. ECO4 can also fund heat pumps. But for homeowners not on qualifying benefits, the BUS grant is the single biggest incentive in the market, and it only covers heat pumps.

Some local authorities run their own schemes. The Warm Homes Local Grant, part of the £5 billion Warm Homes Plan, covers both technologies in some areas. Cornwall funds solar heavily. Other councils focus on insulation. Check your council's website or use our eligibility checker to see what's available where you live.

Can I Have Both?

Yes. And honestly, if you can afford both, that's the best answer.

A solar-and-heat-pump combination is the strongest setup for cutting energy bills in a UK home. The solar panels generate electricity during the day. The heat pump uses electricity to heat your home and water. Put them together and the panels are powering your heating for free during daylight hours. According to the Energy Saving Trust, a household running both can cut energy bills by 60% to 80% compared to a gas boiler with grid electricity.

Add a battery and you extend that benefit into the evening. A 5kWh battery costs £3,000 to £5,000 and lets you store surplus solar generation for when the sun goes down and the heat pump is still running.

The combined upfront cost is significant. A 4kW solar system plus an air source heat pump, after the BUS grant and 0% VAT, comes to roughly £10,000 to £16,000. But the combined savings of £1,000 to £1,500 a year mean payback in 7 to 12 years, with 15 to 20 years of near-free energy after that.

If budget is the constraint, do the heat pump first and add solar in year two. The heat pump delivers bigger immediate savings on your heating bill, and the BUS grant won't last forever. Solar can wait. The 0% VAT runs until March 2027, and panels keep getting cheaper.

What Should I Do First?

This depends on three things: what you heat with, what your roof looks like, and what you can spend.

You heat with oil or LPG

Heat pump. No question. You're paying through the nose for fuel, and the BUS grant makes the switch affordable. An air source heat pump replacing an oil boiler could save you £800 to £1,400 a year. That's a payback of 4 to 7 years after the grant. Explore the best heat pump brands to start comparing.

You have a working gas boiler

This is the trickier call. If your boiler is under five years old, solar panels make more sense right now. You get immediate electricity savings without ripping out a perfectly good boiler. When the boiler eventually dies, switch to a heat pump and let the solar panels power it.

If your boiler is over ten years old or on its last legs, go straight to the heat pump. You're going to need a new heating system soon anyway, and the £7,500 BUS grant won't be around forever. Better to claim it now than gamble on it still being available in three years.

Your roof is perfect but your budget is tight

South-facing, unshaded, 30-degree pitch? Solar panels are hard to argue against. A 4kW system at £6,500 pays for itself in 8 to 10 years and runs for 25 to 30 with minimal maintenance. No moving parts, no servicing costs, no noise. For more on pricing, see our solar panel cost guide.

You want to future-proof

The government has signalled that new gas boilers will be phased out, with a ban on new installations expected by 2035. If you're thinking long term, a heat pump installation gets you ahead of that curve. Solar adds to the picture but doesn't solve the heating question.

The Comparison Table

Factor	Solar Panels	Heat Pump	Best for
Upfront cost (after grants)	£5,500–£8,000	£4,500–£8,000	Similar
Annual saving (gas home)	£500–£700	£400–£600	Solar, marginally
Annual saving (oil/LPG home)	£500–£700	£800–£1,400	Heat pump
Grant available	0% VAT (saves £1,000–£1,500)	BUS £7,500	Heat pump
Installation time	1–2 days	3–5 days	Solar
Maintenance	Almost none	Annual service, £100–£200	Solar
Lifespan	25–30 years	20–25 years	Solar
Works in winter	Reduced output	Full capacity	Heat pump
Noise	Silent	40–55 dB (outdoor unit)	Solar
Planning permission	Usually not needed	Usually not needed	Even

Environmental Impact

A heat pump cuts more carbon than solar panels in most homes. Replacing a gas boiler with an air source heat pump reduces heating emissions by around 40%, according to the Energy Saving Trust. A 4kW solar system offsets roughly 1 to 1.5 tonnes of CO2 per year.

The combination of both is where the real impact sits. A home running a heat pump powered partly by its own solar panels is about as low-carbon as a UK home can get without a full retrofit.

If your main motivation is environmental rather than financial, the heat pump should come first. Heating is the biggest source of household carbon emissions.

Planning Permission and Practicalities

Most solar installations and air source heat pumps fall under permitted development in England, meaning no planning permission needed. The exceptions: listed buildings, conservation areas, and heat pumps that breach noise limits at the boundary. Ground source heat pumps with boreholes may need additional consent.

Solar needs a suitable roof. South-facing is ideal, east or west works at about 80% efficiency, north-facing is rarely worth it. You need roughly 20 square metres of roof space for a 4kW system.

Heat pumps need outdoor space for the unit, about the size of a large suitcase. They also work best in well-insulated homes with larger radiators or underfloor heating. If your home has poor insulation and small radiators, you may need fabric upgrades first. Check your EPC rating to understand where your home stands.

Open the eligibility checker. Two minutes. You'll see which grants apply to your home and whether solar, a heat pump, or both makes the most sense for your situation.