Solar Panels in the UK: Cost Installed, Real-World Output, Grants and Whether They're Worth It

Solar panels are the biggest-ticket item in UK home energy, and the economics have quietly improved: hardware prices fell for most of a decade, VAT is zero-rated, and export tariffs now pay meaningful money for surplus generation. That doesn’t make solar panels automatically worth it for every roof — orientation, daytime usage and how long you’ll stay in the house still decide the answer.

This guide covers what solar panels cost installed in 2026, the output you can realistically expect, the grants and export payments that exist, and how to run the worth-it sums for your own house.

Solar panel cost: installed prices in 2026

For a standard pitched-roof installation with scaffolding, an MCS-certified installer and a string inverter, realistic installed prices look like this:

VAT on domestic solar — panels, batteries and installation — is zero-rated until 31 March 2027, which is already reflected in the ranges above.

Quotes move up for slate or fragile roofs, three-storey scaffolding, in-roof mounting and microinverters or optimisers (worth it on shaded roofs, cosmetic elsewhere). As with any trade, the national lead-generation sites tend to quote high; two or three local MCS installers plus a quote from your energy supplier gives you a real market picture. MCS certification is non-negotiable — without it you can’t register for export payments.

Solar panel output: what a UK roof actually generates

The number that matters is annual yield per kWp installed. In the UK a south-facing, unshaded roof at a typical 30–40° pitch produces roughly 850–950kWh per kWp per year — so a 4kWp system delivers around 3,400–3,800kWh, close to an average household’s annual electricity use.

Adjustments that matter:

• East or west facing: lose roughly 15% annually versus south; an east–west split spreads the solar panel output across morning and evening, which often increases the share you use.
• North of Manchester: knock off another 5–10%; solar still works in Scotland, the yield is just lower.
• Shading: a chimney shadow across two panels drags a whole string down — this is the one genuine case for optimisers or microinverters.
• Season: December output is around a tenth of June’s. Solar pairs with, but doesn’t replace, your winter heating strategy — see our air source heat pump guide for the other half of that equation.

Panel degradation is slow: good panels are warranted to hold about 85–88% of their output after 25 years.

Solar panel grants, zero VAT and export payments

There is no blanket solar grant in the UK, but three mechanisms change the maths:

• Zero VAT on panels, batteries and installation until March 2027 — effectively a 20% discount baked into every quote.
• Warm Homes Plan funding — the successor arrangements to ECO4 can fund solar panels for low-income and benefit-receiving households, applied for through your council or the government’s Improve your home’s energy efficiency service.
• The Smart Export Guarantee (SEG) — suppliers must pay for exported electricity. Rates range from a token 1p to 15p+ per kWh on the best fixed tariffs, and the gap between a lazy default rate and a good one is worth £150–£300 a year on a 4kWp system. You don’t have to sell to the supplier you buy from.

Treat any “government solar scheme” cold call as the scam it almost certainly is — legitimate routes never charge an application fee.

Are solar panels worth it? Running the numbers

A worked example for a 4kWp, £6,500 system generating 3,600kWh a year, at a 27p/kWh unit price and a 12p SEG rate:

Against 25-year panel warranties, all three cases clear payback with a decade or more of effectively free electricity to spare — the return improves the more daytime electricity you use, which is why retired households and home workers see the best numbers.

When are solar panels not worth it? A heavily shaded or north-only roof, a planned house move within five or six years (panels add less to sale price than they cost), or a roof due for recovering — replace the roof first, then mount panels.

Batteries deserve their own sum: £2,500–£5,000 buys 5–10kWh of storage that lifts self-use towards 80%, but at current prices the battery usually pays back slower than the panels it serves. If your EPC matters — for a sale or a rental — note that solar panels are one of the quickest ways to add points; our EPC rating guide shows where they land in the band calculations, and a smart thermostat squeezes more value from every kWh the roof produces.

Frequently asked questions