Powered land · Windsor and Maidenhead, England
1.55 ha brownfield site at St Marks Hospital, Maidenhead, Windsor and Maidenhead
A brownfield site of 1.55 ha in Windsor and Maidenhead, England, on the brownfield land register as previously developed land. It lies 1.06 km from the Cordwallis Primary substation (Southern Electric Power Distribution plc), which has 6.48 MVA of demand headroom and none for generation.
Owner, grid capacity and planning status on request.We do not publish owners. Ask us and we look up the registered owner of this site at the land register, the headroom and connection queue at the nearest substation and its planning history, and find out whether the site is available.
Request owner, grid and planningFacts
Every value links to its source. Licences and last-checked dates are per row.
| Fact | Value | Source |
|---|---|---|
| Area | 1.55 ha (the area its register gives) | Rare Context powered-land sites · ODbL 1.0 · checked 25 Oct 2026 |
| Site from | Brownfield land register (England) | Rare Context powered-land sites · ODbL 1.0 · checked 25 Oct 2026 |
| Address | St Marks Hospital, Maidenhead | planning.data.gov.uk · record · Open Government Licence v3.0 · checked 24 Oct 2026 |
| Status | Undeveloped (not-permissioned) | planning.data.gov.uk · record · Open Government Licence v3.0 · checked 24 Oct 2026 |
| Owner type | Public (owned-by-a-public-authority) | planning.data.gov.uk · record · Open Government Licence v3.0 · checked 24 Oct 2026 |
| Register reference | AL23 (planning authority Royal Borough of Windsor and Maidenhead) | planning.data.gov.uk · record · Open Government Licence v3.0 · checked 24 Oct 2026 |
| Register entry | Brownfield site: St Marks Hospital, Maidenhead | planning.data.gov.uk · record · Open Government Licence v3.0 · checked 24 Oct 2026 |
| Location | Windsor and Maidenhead, England | Rare Context powered-land sites · ODbL 1.0 · checked 25 Oct 2026 |
| Coordinates | 51.5267, -0.7437 (the register's point for the site) | Rare Context powered-land sites · ODbL 1.0 · checked 25 Oct 2026 |
| Nearest substation | Cordwallis Primary (1.06 km, register point to the substation's mapped point) | Rare Context powered-land sites · ODbL 1.0 · checked 25 Oct 2026 |
| Substation voltage | 33 kV (levels 33, 11 kV) | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
| Substation operator | Southern Electric Power Distribution plc | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
| Demand headroom at the substation | 6.48 MVA | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
| Generation headroom at the substation | 0 MW | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
| Congestion (offtake) at the substation | None (green on the heat map) | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
| Congestion (feed-in) at the substation | Full (red on the heat map, limited by upstream thermal capacity) | SSEN Distribution data portal · CC BY 4.0 · checked 24 Oct 2026 |
The register gives a point and an area, not an outline: the distance runs from that point, so the site's edge can be closer to the substation.
How it compares
#83 of 107 sites in Windsor and Maidenhead and #5,153 of 6,229 in the United Kingdom by site score. Larger than 14% of the sites in Windsor and Maidenhead. Closer to its substation than 57% of them.
| Part | This site | Points | Of |
|---|---|---|---|
| Area | 1.55 ha | 0 | 30 |
| Distance to the substation | 1.06 km | 14.1 | 30 |
| Demand headroom at the substation | 6.48 MVA | 6.5 | 40 |
| Site score | 21 | 100 |
How the site score works in the United Kingdom · Search sites in Windsor and Maidenhead
Nearby sites on the same substation
10 other sites have Cordwallis Primary as nearest substation and would compete for its capacity.
- 2 ha brownfield site at DTC Research, Belmont Road, Maidenhead, Windsor and Maidenhead0.22 km · score 33
- 44 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.24 km · score 29
- 1 ha brownfield site at School on College Avenue, Windsor and Maidenhead0.49 km · score 29
- 39 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.59 km · score 23
- 31 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.65 km · score 20
- 37 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.8 km · score 19
- 29 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.63 km · score 19
- 28 ha site near Cordwallis Primary substation, Windsor and Maidenhead1.66 km · score 19
- 1.25 ha brownfield site at Cookham Gas holder, Whyteladyes Lane, Cookham, Windsor and Maidenhead2.72 km · score 6
- 1 ha brownfield site at Gas Holder Station Whyteladyes Lane Cookham Maidenhead, Windsor and Maidenhead2.7 km · score 6
Data on this page
- Supported by National Energy SO Open Data. NESO GIS boundaries for GB DNO licence areas, NESO Open Data Licence.
- Source: Office for National Statistics licensed under the Open Government Licence v.3.0. Contains OS data © Crown copyright and database right 2026. ONS Open Geography: Local Authority Districts, Open Government Licence v3.0.
- Contains public sector information licensed under the Open Government Licence v3.0. planning.data.gov.uk, Open Government Licence v3.0.
- Rare Context. Rare Context powered-land sites, ODbL 1.0.
- SSEN Distribution. SSEN Distribution data portal, CC BY 4.0.