We design the heat pump first, from the room-by-room heat loss, and then look at how solar and storage could work with it. PV panels and batteries are quoted separately from the heat pump, after a roof survey, and the controls are set so the heat pump makes use of solar generation when it is available. See heat pump controls and tariffs for how timing and tariffs fit in.
Roof orientation and shading vary street by street in South Glamorgan, so solar is assessed on each roof individually. Homes in South Glamorgan with existing panels can often have the heat pump set to heat water from their daytime output. Across South Glamorgan and South Glamorgan, winter solar output is modest, so our heat pump designs never rely on it for heating.
Who it suits
- Homes with existing solar PV that currently export much of their output
- Households at home during the day or with flexible hot water timing
- Homes with a roof facing anywhere from east through south to west, with little shading
- Homeowners planning a heat pump who want to add panels at the same time
Grants and rules for heat pumps in Wales
In Wales the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027; £2,500 for air-to-air). The MCS-certified installer named in your quote applies to Ofgem for you, and the grant comes off your quote.
There is no VAT on installing a heat pump anywhere in the UK, Wales included, until 31 March 2027. Planning rules for heat pumps in Wales are set by the Welsh Government and differ from England's, so the surveyor checks the unit position against them.
Prices
Solar panels and batteries are quoted separately after a roof survey. For heat pump system prices see the guide prices.
Towns we cover in South Glamorgan
We cover 6 towns in South Glamorgan for heat pumps with solar panels and batteries. Each links to local guide prices and the grant position for Wales.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Cardiff | CF10 | Penarth | 7 h 50 min |
| Barry | CF62 | Dinas Powys | 7 h 51 min |
| Penarth | CF64 | Dinas Powys | 7 h 50 min |
| Cowbridge | CF71 | Llantwit Major | 7 h 50 min |
| Dinas Powys | CF64 | Penarth | 7 h 50 min |
| Llantwit Major | CF61 | Cowbridge | 7 h 50 min |
Heat pumps with solar panels and batteries questions
Is a solar diverter useful with a heat pump?
It can be, but less so than with a gas boiler. A diverter heats water through the immersion heater, which turns one unit of electricity into one unit of heat, while a heat pump typically makes around three. Scheduling the heat pump to heat water at midday usually uses solar more efficiently, with a diverter adding top-ups on very sunny days.
How much do solar panels and a battery cost with a heat pump?
Solar PV and batteries are quoted separately from the heat pump, because the price depends on your roof, the number of panels, scaffolding, the inverter and any battery size. We survey the roof and give a written quote for that part of the work. The heat pump itself is priced from its own guide ranges, shown on our prices page.
Can solar panels run my heat pump in winter?
Only partly. In midwinter, solar panels typically generate a small fraction of their summer output, and the shortest days coincide with the highest heating demand. Panels may help on bright winter afternoons, but most winter heating will run on grid electricity or a battery charged from a cheaper overnight tariff. Solar contributes most to hot water from spring to autumn.
Should I fit solar panels before or after a heat pump?
Either order works, but planning both together helps. Knowing the heat pump's electricity use helps size the panels and any battery, and the electrical work for both can be coordinated, including the consumer unit and any notification to the network operator. If you already have panels, the heat pump controls can be set to use their output for hot water.

