Commercial solar in Hertsmere

Solar in Hertsmere in figures

What the figures show

Capacity in Hertsmere has grown by 67% since the end of 2020, close to the UK as a whole (69%). In 2025 alone it rose from 19.1 MW to 20.0 MW.

There are 32.2 installations for every 1,000 households, below the East of England median of 73.8 and below the UK median of 67.0. That is 329th of 361 council areas, and 44th of 45 in East of England.

The average installation is 14.6 kW, about twice a typical home system, so larger commercial, farm and ground-mounted systems make up a good share of the capacity.

What a business roof in Hertsmere could generate

Modelled with PVGIS for the centre of Hertsmere, a south-facing roof at 30 degrees produces about 1,009 kWh per kWp a year. That is 169th 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

Hertsmere follows the national planning rules for England. Permitted development rights for non-domestic rooftop solar were widened in December 2023, including removal of the old 1 MW limit, but conditions still apply, especially for listed buildings and conservation areas. Ground-mounted arrays and carports usually need an application to the 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 East of England 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 England.

Nearby council areas

• Barnet, about 5 miles away
• Watford, about 6 miles away
• Harrow, about 7 miles away
• Welwyn Hatfield, about 7 miles away
• St Albans, about 7 miles away
• Three Rivers, about 8 miles away

Or see every council area and the East of England 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.