Commercial solar in Carmarthenshire

Solar in Carmarthenshire in figures

What the figures show

Capacity in Carmarthenshire has grown by 79% since the end of 2020, close to the UK as a whole (69%). In 2025 alone it rose from 165.9 MW to 210.0 MW.

There are 120.7 installations for every 1,000 households, above the Wales median of 83.9 and above the UK median of 67.0. That is 40th of 361 council areas, and 8th of 22 in Wales.

The average installation is 20.6 kW, several times a typical home system of about 4 kW, so solar farms and large commercial or farm roofs make up much of the capacity here.

What a business roof in Carmarthenshire could generate

Modelled with PVGIS for the centre of Carmarthenshire, a south-facing roof at 30 degrees produces about 968 kWh per kWp a year. That is 223rd of 361 council areas; the UK median is 998 kWh.

Same sums as our commercial solar calculator: illustrative, not a quote. East- or west-facing roofs, shading and how much power you use in daylight all move these figures, and a company paying corporation tax can usually shorten the payback with capital allowances. See the cost guide for price ranges by system size.

Planning and grid connection

Many non-domestic roofs are covered by the Welsh permitted development order (Part 43), with conditions for listed buildings, conservation areas and protected land. England's December 2023 changes do not apply in Wales. Ground-mounted arrays usually need an application to Carmarthenshire council, or to a national park authority inside a national park. Our planning permission guide sets out the conditions.

Most commercial systems need G99 approval from the local network operator before they are switched on. The operator follows the postcode rather than the council boundary: our Wales page covers the operators in the region, and the Energy Networks Association postcode tool confirms yours. See G99 and DNO applications.

For funding, see grants and reliefs in Wales.

Nearby council areas

• Swansea, about 19 miles away
• Neath Port Talbot, about 26 miles away
• Pembrokeshire, about 30 miles away
• Ceredigion, about 30 miles away
• Bridgend, about 34 miles away
• Merthyr Tydfil, about 37 miles away

Or see every council area and the Wales page.

Where these figures come from

Installations, capacity, generation and households: Department for Energy Security and Net Zero, Regional Renewable Statistics, renewable electricity by local authority 2014 to 2025 (workbook). They cover all solar PV, homes and businesses, including ground-mounted schemes. Yield: PVGIS 5.3 (European Commission Joint Research Centre), SARAH3 data and 14% system losses, for the council area's centre point (ONS boundaries, December 2024), modelled 4 November 2026. Distances are between centre points.