Solar Panels South Wales: Costs, Installers & Grants
South Wales is the sunniest part of the country for solar, with Cardiff, the Vale of Glamorgan and the Gower coast receiving 950–1,000 kWh per kWp a year, on par with much of southern England. From the M4 corridor cities of Cardiff, Swansea and Newport to the valley towns, a typical 4 kW system pays for itself in roughly 9–12 years and earns export income on top.
Quick Answer
Solar panels in South Wales cost £6,600–£8,500 for a typical 4kW system in 2026, with 0% VAT. South Wales is the best region in Wales for solar, generating 950–1,000 kWh per kWp a year, so a 4kW system produces around 3,400–4,000 kWh annually. Eligible low-income households can get free solar through the Welsh Government's Nest scheme. We list MCS-certified installers across Cardiff, Swansea, Newport and every South Wales county.
Last updated June 2026
Fact-checked by John Rooney, Solar Energy Editor. Editorial policy
Solar panel installers in South Wales
We list MCS-certified solar panel installers across every South Wales county and unitary authority. MCS certification is what makes your installation eligible for the Smart Export Guarantee and 0% VAT, so every installer below holds current MCS status. Browse by area and request free quotes:
Carmarthenshire
Swansea
Neath Port Talbot
Bridgend
Vale of Glamorgan
Rhondda Cynon Taf
Merthyr Tydfil
Cardiff
Caerphilly
Blaenau Gwent
Torfaen
Newport
Monmouthshire
Solar panels in Cardiff, Swansea & Newport
The three biggest South Wales cities each have their own solar profile and installer listings, with local generation estimates and town-level data:
Solar panels Cardiff
MCS-certified installers, typical costs and generation estimates for Cardiff.
Solar panels Swansea
MCS-certified installers, typical costs and generation estimates for Swansea.
Solar panels Newport
MCS-certified installers, typical costs and generation estimates for Newport.
How much do solar panels cost in South Wales?
Prices in South Wales track the wider UK market. The figures below are installed prices including 0% VAT (zero-rated until 31 March 2027), and reflect what homeowners across Cardiff, Swansea, Newport and the valleys typically pay.
| System Size | Panels | Installed Cost | Annual Output |
|---|---|---|---|
| 3 kW | 7–8 | £5,700–£7,000 | ~2,700 kWh |
| 4 kW (standard) | 10 | £6,600–£8,500 | ~3,600 kWh |
| 5 kW | 12 | £8,300–£10,200 | ~4,500 kWh |
| 6 kW | 14 | £10,000–£12,460 | ~5,600 kWh |
See our full UK solar panel cost guide for battery pricing, payback maths and the savings model behind these figures.
Free solar panels and grants in South Wales
South Wales households have access to the same Wales-wide support schemes. The two routes to free or funded solar are:
Nest (Welsh Government)
The Welsh Government's Nest scheme funds free solar panels and other energy efficiency measures for eligible fuel-poor households. You generally need to own your home or rent privately, have a low EPC rating, and receive a means-tested benefit such as Universal Credit or Pension Credit.
ECO4
The UK-wide ECO4 scheme, delivered by energy suppliers, can also fund free or heavily subsidised solar for qualifying low-income households across South Wales, often alongside insulation upgrades.
Full eligibility detail is in our Solar Panels Wales guide and UK solar grants page.
How much sun does South Wales get?
South Wales is the strongest solar region in the country. The south coast and the Vale of Glamorgan get the most, with the valleys only marginally behind. Generation figures are for south-facing panels at optimal tilt:
| Area | Output per kWp (kWh/year) | 4 kW System Output |
|---|---|---|
| Cardiff / Vale of Glamorgan | 950–1,000 | ~3,800–4,000 kWh |
| Swansea / Gower | 940–990 | ~3,760–3,960 kWh |
| Newport / Monmouthshire | 930–980 | ~3,720–3,920 kWh |
| South Wales valleys | 900–960 | ~3,600–3,840 kWh |
Based on EU PVGIS satellite irradiance data. Actual output depends on panel efficiency, shading and orientation.
Solar Panels South Wales FAQ
How much do solar panels cost in South Wales?
A typical 4kW solar system in South Wales costs £6,600–£8,500 installed, including 0% VAT, in 2026. Smaller 3kW systems start around £5,700 and larger 6kW systems reach £12,460. Adding battery storage typically costs £3,000–£6,500 more depending on capacity.
Who are the best solar panel installers in South Wales?
The best installers are MCS-certified, have strong Google and Trustpilot reviews, and cover your area. We list MCS-certified installers across Cardiff, Swansea, Newport and every South Wales county. Get at least three quotes for the same specification and compare totals, equipment and warranties.
Can I get free solar panels in South Wales?
Yes, if you qualify. The Welsh Government's Nest scheme provides free solar panels to eligible fuel-poor households who own or privately rent, have a low EPC rating, and receive a means-tested benefit. The UK-wide ECO4 scheme can also fund free solar for qualifying low-income households in South Wales.
Is South Wales good for solar panels?
South Wales is the best region in Wales for solar and comparable to much of southern England. Cardiff, the Vale of Glamorgan and the Gower receive 950–1,000 kWh per kWp a year, enough for a 4kW system to generate around 3,800–4,000 kWh annually. Solar works on cloudy days too, just at reduced output.
Do I need planning permission for solar panels in South Wales?
In most cases no. Roof-mounted solar panels are permitted development under Welsh planning rules, provided they sit within 200mm of the roof and do not rise above the ridge. Listed buildings, conservation areas and ground-mounted arrays may need permission. Check with your local planning authority if unsure.
How long do solar panels take to pay back in South Wales?
A typical 4kW system in South Wales pays back in roughly 9–12 years, helped by the region's strong sunlight and Smart Export Guarantee income for surplus electricity. Pairing panels with a battery raises self-consumption and can shorten payback further.
Related guides
Related Guides
Solar Panels Wales
Costs, the Nest free solar scheme, Welsh grants and installers across Wales.
Solar Panel Costs
Full cost breakdown and payback periods.
Solar Incentives
0% VAT, Smart Export Guarantee, ECO4, and business capital allowances.
Free Solar Panels
Free solar panel schemes: ECO4, GBIS, rent-a-roof history, and scam warnings.
Best Solar Installers UK
Guide to choosing the best solar installer in the UK.
Smart Export Guarantee
Best SEG tariffs compared. Earn 3–15p/kWh selling solar electricity back to the grid.
Sources
- Nest, Welsh Government energy efficiency scheme
- EU PVGIS, solar irradiance data
- MCS, Microgeneration Certification Scheme
John Rooney is the founder of Solar Info and has been covering the UK solar energy market since 2023. He researches every battery and inverter brand against manufacturer datasheets, MCS and Ofgem data, and feedback from the MCS-certified installers in our directory before publishing.
Get Solar Quotes in South Wales
Free, no-obligation quotes from MCS-certified installers across Cardiff, Swansea, Newport and the South Wales valleys.