Solar Panels and Heat Pumps Together UK 2026 — The Complete Guide

A gas boiler burns fuel to create heat. An air source heat pump moves heat from outside air into your home using electricity — typically producing 3–4 units of heat for every 1 unit of electricity consumed. Solar panels generate free electricity from your roof. Put the two together and you are running a highly efficient heating system largely on energy you generate yourself. That is the combination that is attracting serious interest from UK homeowners in 2026.

Why Heat Pumps and Solar Panels Are a Natural Pair

The core logic is simple. A gas boiler creates heat by burning gas — a fuel you buy, a fuel whose price you cannot control, and a fuel that generates carbon emissions. An air source heat pump (ASHP) creates heat using electricity. It does not generate heat directly; it moves heat from the outside air into the home. For every kilowatt of electricity it consumes, a well-installed ASHP delivers 3–4 kilowatts of heat (a coefficient of performance, or COP, of 3–4).

Solar panels generate free electricity from your roof. That electricity can power your heat pump directly when the sun is shining. In spring and autumn — when UK solar generation is reasonable and the heat pump is running at its most efficient (milder outdoor temperatures improve COP) — you can run your heating system largely for free during daylight hours.

This is why the combination attracts attention. Neither system alone is as efficient as the pair. Solar without a heat pump exports surplus electricity cheaply. A heat pump without solar buys electricity at full price. Together, the solar generation fuels the heat pump and the heat pump makes each unit of solar generation go much further than it would powering standard appliances.

How the Two Systems Work Together

A typical air source heat pump draws 2–4kW of electricity continuously while running. In heating mode during mild weather, demand sits at the lower end of that range. In very cold weather or when heating a large property, it draws more.

A 4–5kWp south-facing solar system in the East Midlands or Buckinghamshire generates approximately 3–5kW during peak daylight hours (roughly 10am–3pm on a clear day). This means that for several hours each day, your solar panels can supply the heat pump’s full electricity demand with no grid draw at all.

The operational picture:

• Clear summer day: Solar panels generate 3–5kW. Heat pump runs on solar power entirely during daylight, heating the home and hot water at no electricity cost. Surplus solar charges a battery or exports to grid.
• Mild spring/autumn day: Solar generates 2–3kW for several hours. Heat pump draws 2–3kW. Net grid draw during daylight hours close to zero. More of the day is powered by solar than not.
• Cold winter day: Solar generation lower (1–2kW for fewer hours). Heat pump works harder and draws more power. More grid electricity is consumed. This is when the system is least efficient, but still far cheaper than gas at gas boiler efficiency.

Adding a battery into the system extends the benefit. Instead of exporting unused solar at 10–15p, the battery stores it. In the early evening when the heat pump runs its peak heating cycle (warming the house for the evening) and solar generation has stopped, the battery discharges to power the heat pump rather than the household buying grid electricity at 24.67p.

Sizing Solar for a Heat Pump

A home with an air source heat pump typically uses 3,000–5,000 kWh per year just for space heating and hot water. This is separate from general household electricity (lights, appliances, cooking) which adds another 2,500–3,500 kWh/yr for a typical 3-bed home.

Total annual electricity demand for a heat pump home: 5,500–8,500 kWh/yr.

A 5kWp south-facing solar system in Milton Keynes generates approximately 4,750 kWh/yr. That covers roughly 55–85% of a heat pump household’s total annual electricity demand, depending on consumption patterns and orientation.

However, the match between solar generation and heat pump demand is seasonal:

• Summer: high solar generation, low heating demand. Large solar surplus — exports to grid or charges battery.
• Winter: low solar generation, high heating demand. More grid electricity required.
• Spring/Autumn: the sweet spot. Moderate solar generation and moderate heating demand overlap well.

This seasonal mismatch is why battery storage is particularly valuable in a heat pump home. A 10kWh battery absorbs daytime solar generation and dispatches it in the evening heating cycle, reducing the amount of expensive grid electricity consumed when demand is highest.

Boiler Upgrade Scheme: £7,500 Grant

The Boiler Upgrade Scheme (BUS) is the UK government’s primary grant for replacing fossil fuel boilers with low-carbon heating. In 2026, the grant for an air source heat pump is £7,500.

Key conditions:

• Available in England and Wales only (Scotland has its own schemes).
• The heat pump must replace a fossil fuel heating system (gas boiler, oil boiler, direct electric).
• The property must have an EPC rating of D or above (unless the heat pump forms part of a fabric improvement plan).
• The heat pump must be installed by an MCS-certified heat pump installer.
• The grant applies to the heat pump installation cost, not to solar panels.
• Expires March 2028. If you are planning a heat pump, do not wait.

The grant is claimed by the installer, not the homeowner. Your MCS-certified heat pump installer submits the application. You simply pay the net cost (total minus £7,500). There is no paperwork burden on you beyond providing property details.

Combined Costs in 2026

Let us put real numbers to a full heat pump + solar + battery installation in 2026:

Component	Cost Range	Notes
Air source heat pump	£9,000–£13,000	Before BUS grant
BUS grant	–£7,500	Deducted at point of installation
Net heat pump cost	£1,500–£5,500	After grant
5kWp solar panels	£7,000–£9,000	0% VAT applies
10kWh battery storage	£4,500–£6,000	0% VAT applies when installed with solar
Total after BUS grant	£13,000–£20,500	Full system: heat pump + solar + battery

These are indicative ranges. A smaller property with a straightforward installation will sit toward the lower end. A larger property, more complex roof, or premium equipment adds cost. The solar and battery elements can be installed in phases if budget requires: solar first, battery later.

Savings: What to Expect

This is where the numbers become compelling. Consider a typical 3-bed UK home previously on a gas boiler:

Current costs (gas boiler):

• Gas for heating + hot water: approximately £1,300–£1,500/yr (at current gas price cap)
• Electricity for household use: approximately £500–£700/yr
• Total energy bills: approximately £1,800–£2,200/yr

With heat pump + 5kWp solar + 10kWh battery:

• Heat pump electricity draw: 3,500 kWh/yr for heating + hot water
• Of which solar covers: approximately 1,500–2,000 kWh/yr (depending on season)
• Remaining from grid: approximately 1,500–2,000 kWh/yr × 24.67p = £370–£494
• General household electricity: largely covered by solar, net grid draw minimal
• SEG export income: modest contribution (say £80–£150/yr)
• Total estimated electricity costs: £400–£600/yr

Net saving versus previous gas heating: approximately £1,200–£1,600 per year. Over 10 years that is £12,000–£16,000 in bill savings, in addition to the value of not being exposed to gas price volatility.

Payback on the investment (£13,000–£20,500 total after grant) at £1,200–£1,600/yr saving: 8–17 years. This is longer than a solar-only install, but the system lasts 20–25 years, carbon emissions are dramatically reduced, and you are insulated from future gas price increases.

Important Note: What Depth of Light Installs

Depth of Light is MCS and NAPIT certified for solar panels, battery storage, and EV charger installation. We do not install heat pumps.

However, we work regularly alongside heat pump installers and we are very experienced in sizing and configuring solar and battery systems to complement heat pump installations. If you are planning a heat pump and want to get the solar right, we can:

• Advise on optimal solar system size for your heat pump and property
• Recommend battery capacity that maximises heat pump solar coverage
• Coordinate timing with your heat pump installer to ensure the systems integrate properly
• Install the solar and battery elements to MCS standards with full certification

For the heat pump installation itself, you need an MCS-certified heat pump installer. Your heat pump installer can apply for the BUS grant on your behalf. We are happy to refer you to trusted heat pump installers in the Milton Keynes and Buckinghamshire area if needed — just ask when you call.

See our solar installation service, battery storage options, and solar + battery packages for the parts we handle. For grants and funding, see our grants and incentives page.

Frequently Asked Questions