Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in
Swipe for next article
Find out how solar, batteries and smart tariffs can work together
Removed from bookmarks
The Independent Home Channel is powered by Octopus Energy.
Solar panels and heat pumps might seem like natural partners. One generates electricity from the sun, while the other uses electricity to heat your home and hot water. In theory, the more electricity you can generate yourself, the less you need to buy from the grid to run your heat pump.
In practice, though, there’s an obvious problem: solar panels produce the most electricity in summer, while a heat pump’s biggest demand for space heating comes during the darker winter months.
So can installing solar panels really make a heat pump cheaper to run? The answer is yes, but the savings make more sense when you look across an entire year rather than expecting your panels to directly power your heating throughout the winter.
“The alignment isn’t perfect,” says Phil Steele, future technologies evangelist at Octopus Energy. “In the summer, your solar is really only supplying your heat pump for hot water production, and in the winter you’re drawing from the grid for your heating and hot water. So really you’ve got to look at it on an annual basis rather than month by month.”
A heat pump uses electricity to transfer heat into your home rather than generating heat by burning fuel. Solar panels can provide some of that electricity whenever they’re generating power and the home can use it.
That means the solar panels don’t make the heat pump itself more efficient. Instead, they can reduce the amount of electricity the household has to import from the grid.
How much difference that makes will depend on factors including the size and orientation of the solar array, the efficiency and electricity consumption of the heat pump, how much electricity the rest of the household uses and how much solar power is consumed in the home rather than exported.
Steele’s own home provides an example of how the technologies can complement one another when solar generation is strong.
See if an Octopus heat pump could save you money.
Advertisement
See if an Octopus heat pump could save you money.
Advertisement
“I am generating 3.6kW, but 3kW is producing free hot water for me effectively at the moment,” he says. “I’ve got our heat pump scheduled to do hot water from midday till 3pm.”
This doesn’t mean every household will be able to cover its hot-water demand with solar, but it illustrates how using electricity when panels are generating can reduce the amount that needs to be bought from the grid.
The seasonal mismatch between the two technologies is significant.
During summer, solar panels can generate substantially more electricity, while a heat pump may have little or no space-heating work to do. During winter, heating demand increases just as shorter days and weaker sunlight reduce solar output.
Energy Saving Trust says that whatever size solar system you install, a heat pump will inevitably need electricity at times when the panels aren’t generating. Households are therefore likely to export surplus electricity during sunny summer periods while still importing electricity to run the heat pump at night and during winter.
However, that doesn’t mean solar and heat pumps are poorly matched.
Energy Saving Trust adds that the average UK domestic solar array is around 3.5 kWp and that, over a full year, a system of that size should generate enough electricity to meet the annual requirements of a heat pump in a typical home. The crucial distinction is that the electricity isn’t necessarily generated at the same time the heat pump needs it.
That’s why Steele argues that the two technologies need to be judged over a year rather than by looking at a winter month’s electricity bill.
There isn’t one figure that will apply to every home, but recent government-commissioned modelling gives an indication of the potential impact.
A May 2026 report for the Committee on Fuel Poverty modelled heat pumps alongside solar panels, batteries and time-of-use tariffs across several illustrative types of home.
For an 84m² semi-detached house with insulated cavity walls, researchers modelled a 4.5kW heat pump and a 3.5kWp solar array. With the heat pump operating at a seasonal performance factor (SPF) of 3.9, annual household electricity costs were modelled at £1,622 without solar and £931 with solar – a difference of £691.
There are important caveats, though. These are illustrative modelled homes rather than predictions for an individual household, and the figures cover all household electricity use, not just electricity consumed by the heat pump.
The modelling also used the Ofgem price cap and tariff assumptions applicable at the time, so actual savings will vary with electricity prices, export payments and individual energy use.
Nevertheless, the research found solar PV reduced modelled electricity costs across all the property types and heat-pump performance levels it examined.
The technologies can potentially complement one another particularly well during warmer months, because a heat pump may still be producing hot water even when the home doesn’t need space heating.
Steele says that’s how the combination works in his own home. In summer, much of the heat pump’s role is producing hot water, while solar generation is at its strongest.
“In the summer, that means your solar is really only supplying your heat pump for hot water production,” he says. “Then the opposite is the case in the winter.”
Depending on your system and household routine, it may also be possible to schedule some electricity use for times when the solar panels are generating strongly, increasing the amount of solar energy consumed within the home.
However, the optimum setup will vary from home to home, so homeowners should follow the operating guidance for their particular heat-pump system rather than changing schedules purely to chase solar generation.
A home battery can help address one part of the timing problem.
Instead of exporting surplus solar electricity generated around the middle of the day, you can store some of it and use it later, potentially including to run your heat pump after the sun has gone down. This can save you significant money because households will often receive less for exporting electricity than they pay to import it later.
But a domestic battery doesn’t solve the bigger seasonal mismatch. You can store electricity generated during the day for use that evening, but you can’t realistically store surplus solar energy produced in July and save it until January.
The government-commissioned modelling demonstrates the additional potential of batteries. In the semi-detached example above, adding a 7kWh battery to the solar system reduced modelled annual household electricity costs further, from £931 to £737.
A battery can also be charged from the grid rather than relying entirely on solar power.
That creates another way of reducing costs: charging the battery when electricity is cheaper on a time-of-use tariff and using the stored electricity when grid prices are higher.
Steele uses Octopus’s Cosy tariff as an example, explaining that a household with solar and battery storage could charge the battery during cheaper tariff periods and then use the stored electricity to help meet heat-pump demand outside those windows.
Yes. By generating electricity at home, solar panels can reduce the amount of grid electricity a household needs to buy, helping to offset the electricity costs associated with running a heat pump.
But don’t expect rooftop solar to directly supply most of your heating through the depths of winter. Solar generation and heating demand simply don’t peak at the same time.
Instead, Steele says homeowners should take a broader view.
Across a year, solar generation can offset a meaningful proportion of household electricity demand, while a battery and suitable tariff can potentially allow more energy to be used when it is most valuable.
Rather than asking whether your solar panels can run your heat pump on a cold January evening, the more useful question is how the two technologies can work together to reduce your home’s overall energy costs across the year.
Join thought-provoking conversations, follow other Independent readers and see their replies
Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in

source