No.31 of 650 · approved, not built MP: Freddie van Mierlo (Liberal Democrat) England

Henley and Thame

Henley and Thame has 151 MW of clean power (all solar) approved and still not built: enough to supply a year's electricity to 55,000 homes. Britain's grid bottlenecks still add to bills here: about £92 a year per household, £3.6m across the constituency's 39,348 homes. A 100 MW battery was refused planning here in 2025; while discharging it could have supplied about 350,000 homes.

Not visible
here

No big wind farm on the national grid is mapped to this constituency, so no switch-off payments show here in national data. Smaller wind farms on the local grid can still be paid to switch off — invisibly. The £ figure for this seat is a floor, not a zero.

how we worked this out

151 MW

of clean power — all solar — approved and still not built, enough to supply a year's electricity to 55,000 homes — about as many homes as this constituency has. Approved at least two years ago; waiting on the grid, not on planning. That is 4.3× the renewable capacity actually running here.

6 projects · planning database (REPD), July 2026 · how we worked this out

£3.6m

is what the grid gap costs this constituency's 39,348 households in a year between them — £92 each, about 51 days of one home's electricity.

The £92 per household is a national figure — identical in every GB seat. Only the seat total varies, with the number of households · NESO · how we worked this out

The waiting list

3 of 6 waiting projects · years since approval

Cornwell Solar Farm 50 MW

4.8 YRS

Harlesford Solar Farm 50 MW

4.6 YRS

Dodwells Solar Farm 50 MW

2.9 YRS

Every approved, unbuilt project

approved 24+ months ago, still not generating · planning database, July 2026

Site	Technology	Enough for	Capacity	Approved	Waiting
Cornwell Solar Farm	Solar Photovoltaics	18,000 homes	49.9 MW	2021-10	4.8 yrs
Harlesford Solar Farm	Solar Photovoltaics	18,000 homes	49.9 MW	2021-12	4.6 yrs
Dodwells Solar Farm	Solar Photovoltaics	18,000 homes	49.9 MW	2023-08	2.9 yrs
Icknield Road, Ipsden - Solar Array & Battery Storage	Solar Photovoltaics	500 homes	1.4 MW	2022-12	3.6 yrs
Lucy Switchgear, Howland Road - Solar Panels	Solar Photovoltaics	100 homes	0.3 MW	2023-12	2.6 yrs
Benson Lane, Crowmarsh - Solar Array	Solar Photovoltaics	—	— MW	2023-04	3.3 yrs

Plus 3 more approved within the last two years.

Batteries

projects of 10 MW and above · planning database, July 2026 · what batteries do →

Site	Size	Status	While discharging
Lower road, Garsington - Energy Storage System	100 MW	refused 2025	could supply ≈350,000 homes
Cowley electricity sub-station	50 MW	operating 2019	could supply ≈175,000 homes

What this page does not show

Smaller wind farms on the local grid are also switched off; national data does not show it, so the £ figure here is a floor, not a zero. Offshore wind is counted nationally, never per seat. The planning database can run a quarter behind reality.

Electricity does not travel from a particular project to particular houses. Everything generated goes into the national grid and everyone draws from that shared pool, so "enough for X homes" is a way of sizing the electricity — not a claim that these homes would be powered by this site. Battery storage is counted separately from generation: it moves power in time rather than making it.

Planning statuses come from the government's planning database (REPD), which records what was decided and when, but not why. Where a project was refused we say so and name the authority; for the reasons, look up the planning reference on that council's own register. How to check any figure on this page →

Read the full method, including everything we cannot see →

What has Freddie van Mierlo said about the grid in Parliament? Search Hansard →

See the full league table Data (JSON)