Dinorwig Power Station
pumped-storage hydroelectric power station in Wales
The Dinorwig Power Station (Welsh: Gorsaf Bŵer Dinorwig, pronounced [dɪˈnɔrwɪɡ]), known locally as Electric Mountain, or Mynydd Gwefru, is a pumped-storage hydroelectric scheme, near Dinorwig, Llanberis in Snowdonia national park in Gwynedd, north Wales. The scheme can supply a maximum power of 1,728 MW and has a storage capacity of around 9.1 GWh (33 TJ).
Purpose
The scheme was built at a time when responsibility for electricity generation in England and Wales was in the hands of the government's Central Electricity Generating Board (CEGB); with the purpose of providing peak capacity, very rapid response, energy storage and frequency control. Dinorwig's very rapid response capability significantly reduced the need to hold spinning reserve on part loaded thermal plant. When the plant was conceived the CEGB used low efficiency old coal and oil fired capacity to meet peaks in demand. More efficient 500 MW thermal sets were introduced in the 1960s, initially for baseload operation only. Dinorwig could store cheap energy produced at night by low marginal cost plant and then generate during times of peak demand, so displacing low efficiency plant during peak demand periods.
There were plans for a pumped storage facility near Exmoor but it was not built. With the increase of renewables such as wind and solar power, the need for storage is expected to increase to deal with intermittency. A 50 MW pumped storage facility at nearby Glyn Rhonwy in disused slate pits was approved in 2013, with an expected cost of £120 million.
The public source identifies “Dinorwig Power Station” as pumped-storage hydroelectric power station in Wales. This brief keeps that definition visible, then builds a research path around Dinorwig, Power and Station.
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Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Jul 1, 2026. The linked authority identifier is Q1146238. VIAF identifies the subject as 420144783046586550433. The Library of Congress control number is sh2005006022. Authority coordinates are 53.118, -4.107. 1 of 5 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2013.
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This entry incorporates text from “Dinorwig Power Station” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.