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- Transmission Line80,968
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Chokepoints
Grid Storage
Ffestiniog hydroelectric plant
10th-largest grid storage in United Kingdom of 12 · top 73% worldwide (#695 of 965)
- Operator
- ENGIE
- Owner
- ENGIE SA
- Status
- operating
- Capacity
- 384 MW
- Technology
- pumped storage
- Commissioned
- 1963
- Also listed as
- A power plant — this site generates as well as stores
Comparable grid storages · United Kingdom · 12 ranked
- #1Dinorwig hydroelectric plant2.0 GW
- #8Cruachan hydroelectric plant440 MW
- #9Glenmuckloch hydroelectric plant400 MW
- #10Ffestiniog hydroelectric plant384 MW
- #11Foyers hydroelectric plant320 MW
- #12Glyn Rhonwy hydroelectric plant100 MW
Grid connection · within 50 km
- Nearest substation
- Trawsfynydd Substation
- Its voltage
- 400 kV
- Distance
- 6.1 km
- Strongest line nearby
- 400 kV
- Substations in range
- 7
Mapped grid infrastructure from OpenStreetMap, whose coverage is excellent in some regions and sparse in others. Nothing shown here means nothing is mappednearby — not that the site is unconnected. Lines are matched on a segment’s midpoint, so a corridor passing directly overhead can be missed; this under-reports rather than invents.
Co-located infrastructure · within 25 km
- Ffestiniog hydroelectric plant0 m · Power Plant · 384 MW · hydro
- 400 kV line6.0 km · Transmission Line
- Trawsfynydd Substation6.1 km · Substation / Converter
- Trawsfynydd nuclear power plant6.3 km · Power Plant · 470 MW · nuclear
- Pentir-Trawsfynydd;Y Ffor-Trawsfynydd7.1 km · Transmission Line
- Garth Cable Compound10 km · Substation / Converter
- Wern 400KV Cable Compound14 km · Substation / Converter
- National Grid Pentir-Trawsfynydd14 km · Transmission Line
- Dinorwig hydroelectric plant18 km · Power Plant · 2.0 GW · hydro
- Dinorwig hydroelectric plant18 km · Grid Storage · 2.0 GW
- Glyn Rhonwy hydroelectric plant20 km · Grid Storage · 100 MW
On the interactive map
Portfolio
SOURCE: Global Energy Monitor · Global Integrated Power, March 2026 (CC BY 4.0)