Seion, Pentir (99.9 MW battery storage)
Seion, Pentir is a 99.9 MW battery storage project in Gwynedd, Wales. Its status in the Renewable Energy Planning Database (July 2026 extract) is: refused on 23 January 2026; the record was last updated on 25 March 2026.
99.9 MWbattery storage
refusedstatus in REPD
25 March 2026record last updated
Gwyneddcouncil area
Planning timeline
| Date | Stage |
|---|---|
| 8 April 2025 | Application submitted |
| 23 January 2026 | Refused by the planning authority |
Project details
- Technology
- battery storage (stand-alone storage)
- Capacity
- 99.9 MW
- Status (REPD)
- refused
- Record last updated
- 25 March 2026
- Operator or applicant
- Brockwell Storage & Solar Limited
- Planning authority
- Gwynedd
- Planning application reference
- C25/0277/18/LL
- Address (REPD)
- S/O B4547 Seion, Pentir, Llanddeiniolen, Caernarfon
- Council area (by location)
- Gwynedd
- Time to decision
- 41 weeks
- Name in REPD
- Seion, Pentir - Battery Energy Storage System
- REPD reference
- 18711
Who decides
| Applications | Gwynedd | UK |
|---|---|---|
| Decided applications (solar, wind, battery) | 19 | 10,236 |
| Refused | 6 (32%) | 19% |
| Solar refused | 3 of 13 | 12% |
| Onshore wind refused | 2 of 3 | 45% |
| Battery storage refused | 1 of 3 | 16% |
| Median time from submission to decision | 17.4 weeks | 17.0 weeks |
| Appeals lodged / allowed | 0 / 0 | — |
Other large projects within 10 km
| Project | Type | MW | Status | km |
|---|---|---|---|---|
| Tyddyn Forgan, Llanddeiniolen | battery storage | 100 | approved, not built | <0.1 |
| Pentir Substation, Pentir | battery storage | 57 | approved, not built | 0.5 |
| Parciau Farm Solar Park | solar farm | 13.9 | operational | 5.5 |
Status and dates as recorded in the Renewable Energy Planning Database (July 2026 extract); the database is compiled from public sources and can lag behind council decisions. Location: REPD grid reference (53.1859, -4.1666).