Kinlochleven hydroelectric scheme

The scheme was consented by the Loch Leven Water Power Acts of 1901 and 1904, the latter of which extended the time available for completion and had some variations in the scheme.Payne 1988, p.6 The scheme was designed by Thomas Meik and Sons, with consulting input from Sir A R Binnie.Paxton & Shipway, 2007, pp.172–174

Construction of the hydroelectric scheme started in 1905, and took approximately four years. The main contractor was Sir John Jackson Ltd, with A H Roberts as the resident engineer. Construction cost about £600,000, or around £60m adjusted for inflation to 2024.{{Cite web |title=Inflation calculator |url=https://www.bankofengland.co.uk/monetary-policy/inflation/inflation-calculator |access-date=2024-05-19 |website=www.bankofengland.co.uk |language=en}}

The workforce was largely Irish Navvies, with around 3,000 men working in squalid conditions. Many died in construction accidents, and were buried in a graveyard beside the dam, with concrete headstones.{{Cite web |date=2010-11-11 |title=BBC One - Making Scotland's Landscape, Scotland's Water, Blackwater Dam |url=https://www.bbc.co.uk/programmes/p00c3k9h |access-date=2024-05-19 |website=BBC |language=en-GB}}

Materials were transferred to the Blackwater Dam construction site by means of an aerial cableway from a wharf on Loch Leven. This was supported on trestles 10–130 ft (3–40 m) high with spans of 100–1,000 ft (30–305 m), and powered by a temporary hydroelectric plant with a {{convert|250|hp|kW}} Pelton wheel. A railway was also constructed between the wharf and the dam. This had two rope inclines of 200 and 600 feet (61 and 183 m), but otherwise generally followed the contours of the valley.

The Blackwater Dam was {{convert|3112|ft|m}} long and {{convert|86|ft|m}} high. It was constructed just upstream of {{Lang|gd|Dubh Lochan}}, and inundated {{Lang|gd|Lochan Inbhir}}, {{Lang|gd|Lochan na Sàlach Uidre}} and {{Lang|gd|Loch a'Bhàillidh}}.{{Cite map|title=One-inch Scotland, 1885-1900|publisher=Ordnance Survey|via=National Library of Scotland Georeferenced Maps|url=https://maps.nls.uk/geo/explore/#zoom=13.2&lat=56.70701&lon=-4.80545&layers=1&b=1&o=100|access-date=2024-05-18}} During construction, it was found the unit weight of concrete made with local aggregate was lower than used in design calculations, so the profile of the dam was amended to give it a wider base, with an overturning factor of safety of 2.28.

From the dam, water is conveyed along a reinforced concrete conduit, {{convert|8|ft|m}} square and {{convert|3.5|mi|km}} long, with a fall of 1 in 1000. After passing through the valve house, the water descends {{Convert|935|ft|m}} through six parallel high-pressure penstocks made of steel, each {{convert|39|in|m}} in diameter and {{convert|5750|ft|m}} long.Payne 1988, pp.6–7

During World War I, due to increasing demands for aluminium, Balfour Beatty was commissioned to construct a dam and aqueduct to bring additional water for the scheme from Loch Eilde Mòr, increasing the catchment to around {{convert|66|sqmi|km2}}. This was constructed by 1,200 German prisoners of war and 500 British troops "of low medical category".Payne 1988, p.8

A temporary smelter was constructed and commenced production in 1907, although this closed after the main works opened in 1909.

The power house originally had 11 Pelton turbines made by Escher Wyss (Zürich). Each turbine was coupled to two 1,000 kW DC generators made by Dick, Kerr & Co., which powered the smelting process. There were also two AC generators for auxiliary power.{{Cite web |title=MHG33837 - Kinlochleven, Power House - Highland Historic Environment Record |url=https://her.highland.gov.uk/Monument/MHG33837 |access-date=2024-05-19 |website=Highland Historic Environment Record}} The total capacity of the scheme was 25 725kW, with the annual output of the hydroelectric scheme reaching 160 GWh, a load factor of around 80%.

To meet the expected increase in demand for Aluminium, the British Aluminium Company drew up plans to further expansion of the scheme to capture water from the catchments of Loch Treig and Loch Laggan which would be transferred to a second powerhouse at Kinlochleven. In 1918, a Provisional Order for this was promoted in Parliament for this, however this was abandoned due to opposition on two main topics. Firstly the transfer of water from the catchment of the Lochy to that of the Leven. Secondly, Inverness County Council wanted to use this water for industrial development in Fort William in Inverness-shire, while Kinlochleven was in neighbouring Argyllshire. A new act was then drawn up for the Lochaber hydroelectric scheme, which instead had the power station in Fort William.Payne, 1988 pp.8–9

In 1994, closure of the smelter was by around the end of the century was announced by the owners at that time Alcan Smelting and Power UK Ltd. It eventually closed in June 2000. The power house building was Grade A listed on 3 August 2004.

Gilkes installed three 10 MW horizontal-axis Francis turbines between 1996 and 2001, in stages while the facility was operating. The first turbine (K1) was installed in 1996, and was controlled by a simple PLC to maintain grid frequency. The other turbines (K2 & K3) were installed in 1999 and 2000. The full system was controlled by a Gilkes digital speed governor, which allows the scheme to operate in an 'island' mode if the grid fails. Flow to each of the three turbines comes from two of the six penstocks, with a new Y-piece and downstream lateral compensator. Each turbine has a peak flow of 4.15 m³/s.{{Cite web |date=2022-08-11 |title=Scottish smelting |url=http://www.waterpowermagazine.com/features/featurescottish-smelting/ |url-status=dead |archive-url=https://web.archive.org/web/20220811135141/http://www.waterpowermagazine.com/features/featurescottish-smelting/ |archive-date=2022-08-11 |access-date=2024-05-18 |website=International Water Power and Dam Construction}}{{Cite web |title=Kinlochleven |url=https://www.gilkes.com/case-studies/kinlochleven |access-date=2024-05-19 |website=Gilkes |language=}}

In April 2002, Kinlochleven the "Declared Net Capacity" (DNC) was downrated to 19.5 MW from the previous 30 MW,{{Cite report |url=https://www.ofgem.gov.uk/sites/default/files/docs/2004/02/6193-renewables_obligation_0.pdf |title=The Renewables Obligation Ofgem's first annual report |date=February 2004 |publisher=Office of Gas and Electricity Markets |page=35 |access-date=2024-05-24}} permitting accreditation under the Renewables Obligation (RO) support mechanism which only applied to hydropower schemes with a DNC under 20 MW. The DNC is the maximum continuous power output of the plant, excluding that used by the facility.

The rules of the RO (Scotland) were changed in 2018, allowing the capacity of the hydropower station to be upgraded back to 27.5 MW, although it only gets RO support for 19.5 MW, the 8 MW increase receives no subsidy.{{Cite web |last=Glen |first=Louise |date=2018-11-16 |title=Hydro plant boost after rule change |url=https://www.pressandjournal.co.uk/fp/news/highlands-islands/1610375/hydro-plant-boost-after-rule-change/ |url-access=subscription |archive-url=https://web.archive.org/web/20240524183059/https://www.pressandjournal.co.uk/fp/news/highlands-islands/1610375/hydro-plant-boost-after-rule-change/ |archive-date=2024-05-24 |access-date=2024-05-24 |website=Press and Journal |language=en-GB}} The upgrade was completed by April 2020, and in the week before 21 April the scheme generated an average of 23.27 MW (approximately 3.9 GWh total).{{Cite web |last=Arnaud |first=Stan |date=2020-04-21 |title=Highland hydro station generating more power to the people |url=https://www.pressandjournal.co.uk/fp/news/highlands-islands/2157640/highland-hydro-station-generating-more-power-to-the-people/ |access-date=2024-05-24 |website=Press and Journal |language=en-GB}}

With the Kinlochleven scheme downrated, plans were drawn up to directly harness the water from Loch Eilde Mòr. A 5 MW scheme was approved by the Scottish Government in July 2011.{{Cite web |last= |date=2011-07-26 |title=Kinlochleven small hydropower scheme approved in Scotland |url=https://www.hydroreview.com/hydro-industry-news/kinlochleven-small/ |access-date=2024-05-25 |website=Hydro Review |language=en-US}}

In 2017, a smaller 2 MW scheme was commissioned. This involved modifications to the original dam and intake, approximately 3 km of new pipework, and a powerhouse on the north bank of the River Leven, with a three-jet horizontal Pelton wheel turbine.{{Cite web |last=Poindexter |first=Gregory |date=2017-10-10 |title=2-MW Loch Eilde Mor small hydropower scheme commissioned in Scotland |url=https://www.hydroreview.com/world-regions/europe/2-mw-loch-eilde-mor-small-hydropower-scheme-commissioned-in-scotland/ |access-date=2024-05-25 |website=Hydro Review |language=en-US}} The scheme cost around £13.6 million to construct, and will contribute an annual community benefit of £5000/MW.{{Cite web |last=Mack |first=Ann |date=2017-10-09 |title=Hydro scheme promises income stream for village |url=https://www.pressandjournal.co.uk/fp/news/highlands-islands/1337727/new-multi-million-pound-hydro-scheme-will-also-pour-cash-into-lochaber-community/ |url-access=subscription |archive-url=https://web.archive.org/web/20240525094045/https://www.pressandjournal.co.uk/fp/news/highlands-islands/1337727/new-multi-million-pound-hydro-scheme-will-also-pour-cash-into-lochaber-community/ |archive-date=2024-05-25 |access-date=2024-05-25 |website=Press and Journal |language=en-GB}}

Planning permission was granted to Green Highland Renewables in March 2019, amended a year later, to construct an 800 kW scheme at the base of the Blackwater Dam. This uses the hydraulic head of the dam to generate additional power. Construction of the scheme was between January and November 2021.{{Cite web |title=18/05815/FUL {{!}} Proposal to install a small generating station at the base of Blackwater Dam, using the water drawn from Blackwater Reservoir before it enters the low-pressure conduit which serve the existing Kinlochleven Hydro Scheme {{!}} Land 5655M SE Of Penstock Cottage Lochaber Road Kinlochleven |url=https://wam.highland.gov.uk/wam/applicationDetails.do?activeTab=documents&keyVal=PJQKX6IHIHX00 |access-date=2024-05-25 |website=wam.highland.gov.uk}}{{Cite web |title=19/05622/FUL {{!}} Installation of generating station at the base of Blackwater Dam (amendments to planning permission 18/05815/FUL) {{!}} Land 5655M SE Of Penstock Cottage Lochaber Road Kinlochleven |url=https://wam.highland.gov.uk/wam/applicationDetails.do?activeTab=documents&keyVal=Q2TFEFIHGPM00 |access-date=2024-05-25 |website=wam.highland.gov.uk}}{{Cite web |date= 28 March 2017|title=The Green Highland Story |url=https://greenhighland.co.uk/our-story-old/ |access-date=2024-05-25 |language=en-GB}}

Water is diverted from one of the three cast-iron pipes {{convert|42|in|m}} in diameter which pass through the base of the dam, through a new turbine and returned to the original stilling pond. The water then flows through the concrete conduit to Kinlochleven.

In 1909 when the smelter was completed, the total annual output of all other smelters in Britain was about 2,500 tons, which was less than one third the designed output of the Kinlochleven smelter. The smelter produced about 8,000 tonnes per year, significantly less than modern plants which produce around 250,000, which meant it was less economical to run.{{Cite web |title=Kinlochleven - a highland village reborn |url=http://www.caledonia.org.uk/socialland/kinlochl.htm |access-date=2024-05-19 |website=www.caledonia.org.uk}}

Peak employment in the smelter was over 700 people, although by January 1999 there were just 96 employees.

A narrow-gauge railway approximately a mile long linked the pier on the southern shore of Loch Leven and the smelter, which operated between 1906 and 1960. It was double track throughout with a gauge of {{convert|3|ft|m}} and overhead electric power at 500–550 V DC, making it the first electric railway in Scotland. Four-wheeled electric locomotives were built in Preston, Lancashire by Dick, Kerr & Co. (who also made the generators for the hydroelectric scheme) to haul freight only.{{Cite web |title=Industrial Railways - Important Private Lines in Great Britain |url=https://www.railwaywondersoftheworld.com/industrial-railways.html |access-date=2024-05-19 |website=Railway Wonders of the World}}{{Cite web |title=Kinlochleven |url=https://canmore.org.uk/site/107303/kinlochleven |access-date=2024-05-19 |website=Canmore |language=}}{{Cite web |date=2010-04-22 |title=Kinlochleven Railway |url=https://hlrco.wordpress.com/scottish-narrow-gauge/constructed-lines/kinlochleven-railway/ |access-date=2024-05-19 |website=Hebridean Light Railway |language=en}}

• {{Cite book |last=Payne |first=Peter Lester |title=The hydro: a study of the development of the major hydro-electric schemes undertaken by the North of Scotland Hydro-Electric Board |date=1988 |publisher=Aberdeen University Press |isbn=978-0-08-036584-8 |location=Aberdeen, Scotland |pages=5–9}}
• {{Cite book |last1=Paxton |first1=Roland |url=https://www.worldcat.org/title/155675101 |title=Scotland - Highlands and islands |last2=Shipway |first2=J. |date=2007 |publisher=Thomas Telford |others=Royal Commission on the Ancient and Historical Monuments and Constructions of Scotland |isbn=978-0-7277-3488-4 |series=Civil engineering heritage |location=London |pages=172–174 |oclc=155675101}}
• {{Cite journal |last=Witherall |first=Raoul |date=Jan–Feb 2000 |title=Alcan winds down oldest operational smelter |url=https://www.proquest.com/docview/1372745991 |journal=Aluminium Today, 12 |volume=12 |issue=1 |url-access=subscription |access-date=2024-05-18 |id={{ProQuest|1372745991}} |via=ProQuest}}

{{Scottish energy}}

Category:Hydroelectric power stations in Scotland

Category:Buildings and structures in Highland (council area)