Tag: Galloway Hydro Scheme

Working with Galloway Glens to boost salmon and trout habitats

Black Water of Dee Restorations

The River Dee in south-west Scotland flows from its source in Loch Dee through the Galloway Hills, firstly to Clatteringshaws Loch, then into Loch Ken, where it joins the Water of Ken.

As in much of Scotland, salmon populations here have struggled, with rod catches at an all-time low. Climate change leading to warmer rivers and seas, commercial farming and changes in food supply have all been blamed.

Fly-fishing on the River Tweed with the iconic Kelso Bridge at the background. Kelso, Scottish Borders, Scotland

In 2019 Drax Group pledged £100,000 over four years to support community initiatives in the Galloway Glens region as part of its efforts to support those living in the areas in which it operates.

One of these projects is the Blackwater of Dee Restoration project which aims to boost salmon stocks by moving natural river sediments past large impoundments such as dams – the first time in Scotland that targeted support has been provided to recreate the natural movement of aggregate along the length of the river. The project is situated downstream of Clatteringshaw Dam which facilitates electricity generation at Drax’s Galloway Hydro-Electric scheme.

Clatteringshaw Dam

Human beings have always had an extensive relationship with rivers. For thousands of years they have provided food, hydration and highways.

Ancient people worshipped rivers: the word Dee is derived from the word Deva, one of the oldest written words in the English language, dating back to 150AD, a Celtic word for goddess.

As civilisations developed, rivers became sources of wealth. Rivers – like coal – powered the industrial revolution with watermills driving many forms of industry. The harnessing of the Blackwater of Dee as a power source in the 1930s was a major feat of human ingenuity which provided power for the country.

As part of this project, Galloway Fisheries Trust has been training an army of volunteers to look after the Dee. These volunteers collect data on the river habitats, the fish and invertebrate populations. They have planted native trees and removed non-native invasive plant species.

It is hoped that the project will signal a genuine kickstart to rebuilding Scotland’s salmon population in the long term.

“Drax is proud to support the Galloway Glens Scheme in the effort to restore salmon stocks,” says Stuart Ferns, Drax’s Galloway Hydro Scheme Operations Manager. Ferns noted the initiative also provides “innovative and exciting learning opportunities for young people across the South of Scotland.”

McNabb Laurie, Galloway Glens Team Leader, believes the scheme is a great example of the private sector working with the not-for-profit sector: “This is the first project of this type in Scotland, another first for Galloway!

“We need to pursue every avenue we can to support salmon and other species in the Dee catchment,” Laurie comments. “Our thanks as always going to National Lottery Heritage Fund for the funding and Scheme partners including Drax, Dumfries & Galloway Council and the Galloway & Southern Ayrshire UNESCO Biosphere.”

Earlstoun Fish Pass: l-r McNabb Laurie, Jamie Ribbens, Rowan McCleary, Stuart Ferns

Read more information about the project or contact the Galloway Fisheries Trust on 01671 403011.

Capacity Market agreements for existing assets

Engineer below Cruachan Power Station dam

RNS: 3530F
Drax Group plc

(“Drax” or the “Company”; Symbol:DRX)

Drax confirms that it has provisionally secured agreements to provide a total of 2,562MW of capacity (de-rated 2,333MW) from its existing gas, pumped storage and hydro assets(1). The agreements are for the delivery period October 2023 to September 2024, at a price of £15.97/kW(2) and are worth £37 million in that period. These are in addition to existing agreements which extend to September 2023.

Drax did not accept an agreement for the 60MW Combined Cycle Gas Turbine (CCGT) at Blackburn Mill.

A new-build CCGT at Damhead Creek and four new-build Open Cycle Gas Turbine projects participated in the auction but exited above the clearing price and did not accept agreements.


Drax Investor Relations: Mark Strafford
+44 (0) 7730 763 949


Drax External Communications: Ali Lewis
+44 (0) 7712 670 888

Website: www.drax.com/uk


  1. Existing assets – gas (Damhead Creek, Rye House, Shoreham and three existing small gas turbines at Drax Power Station), Cruachan Pumped Storage and the Galloway hydro scheme (Tongland, Kendoon and Glenlee).
  2. Capacity Market agreements stated in 2018/19 real-terms, with payments indexed to UK CPI.


How river-powered hydro schemes work

Waterflow outside Glenlee Power Station

Hydro power is one of the most widespread sources of electricity generation in the world – it is also one of the biggest. Nine of the world’s ten largest power stations are hydro powered. Facilities such as the Three Gorges Dam on China’s Yangtze River and the Itaipu Dam (pictured below) on the Brazil-Paraguay border are capable of generating massive amounts of electricity.

Itaipu Dam, hydroelectric power station on the Brazil-Paraguay border

But hydropower can also be very effective at a smaller, more local level, using relatively small rivers. These smaller hydro facilities can bring renewable electricity to remote areas and serve local needs. All they need is an abundance of flowing water to spin their turbines.

In Scotland, two schemes are making use of the country’s plentiful water sources to help the local community, the economy and the surrounding environment.

Turning river waterflow into power

The Lanark and Galloway hydropower schemes are both located in rural Scotland and have been generating power for nearly a century. Despite being more than 95 kilometres apart, they operate in very similar ways.

Lanark (which includes two power stations – Bonnington, with a capacity of 11 MW, and Stonebyres, with a capacity of 6 MW) sits on the River Clyde and began generating power in 1926, making it one of the oldest hydro-electric plants in Great Britain.

Galloway soon followed, coming online in the mid-1930s. It includes a total of six power stations – Glenlee, Tongland, Kendoon, Drumjohn, Earlstoun and Carsfad – eight dams and a network of tunnels and pipelines, giving it a capacity of 109 MW.

Kendoon Power Station Turbine Hall

Kendoon Power Station Turbine Hall

“There was always potential for hydro in the Galloway Hills but there wasn’t demand for 100 MW of power,” explains Stuart Ferns, Operations and Maintenance Manager on the Lanark and Galloway hydro schemes. “However, when the national grid was established in the 1920s it enabled surplus power to be transmitted beyond the local area to Glasgow and further afield.”

Unlike Lanark, which is situated about halfway down the River Clyde, the Galloway scheme spans the entirety of its river system from Loch Doon in the North to Tongland in the south. Both, however, cover a similarly sized catchment area of roughly 1,000 square kilometres.

Where they do differ is in the type of hydropower they generate and the needs they serve for their regions and the wider electricity grid.

Tongland Dam

Tongland Dam

Lanark’s power stations generate electricity through what’s called ‘run-of-the-river’ hydropower, which describes a scheme where there is no dam to stop and store water along the river.

Instead, water from a flowing river is diverted into a power station situated alongside the river. Here the water is used to spin a turbine connected to a generator, before being returned back to the river. Lanark’s two power stations are both positioned alongside naturally occurring waterfalls, which allow them to take advantage of the natural gravitational pressure.

“The Lanark stations run constantly,” says O&M Manager Stuart Ferns. “They will run as long as there is water in the river. And generally, there is always some water available.”

The Galloway system is different. It only generates power when there are peaks in electricity demand. To do this it operates a conventional storage hydro scheme where dams situated along the river are used to create small reservoirs. When demand for electricity peaks – typically between 5pm and 7pm – water is released from these reservoirs and used to spin turbines and generate electricity.

During the day both schemes are monitored and controlled from Glenlee Power Station, halfway down the Galloway route. As night falls, responsibility instead falls to the control room at Cruachan Power Station, more than 200 kilometres away. Around-the-clock monitoring in this way is important as the uncertainty of Scotland’s weather can have effects on the schemes, and on their surrounding environment.

Penstocks leading to Glenlee Power Station

Penstocks leading to Glenlee Power Station

Working with the landscape

Dumfries & Galloway and Lanarkshire are regions defined and dominated by their river systems. As such, extreme weather can lead to occasional natural flooding. The Lanark and Galloway schemes not only have to be diligent in working with extreme weather, but they can actually play a role in monitoring and managing it.

“The Galloway reservoirs help to alleviate flooding because they can store water and help to alleviate flooding downstream,” says Ferns.

Staff at the scheme work closely with local authorities, landowners and the Scottish Environment Protection Agency (SEPA), sharing their weather forecasting and reservoir level data to help them predict which areas will be affected and when roads might need to be closed or even villages evacuated.

The team takes a similar approach to monitoring and protecting the local wildlife. Fish, such as north Atlantic salmon and trout, migrate upstream from the ocean through the Galloway Rivers using manmade fish passes (also known as ‘fish ladders’), which allow fish to bypass dams along the scheme.

Lanark hydro site, River Clyde

Waterfalls on the Clyde at Lanark

Lanark’s natural waterfalls mean it is not a route taken by migratory fish. However, ensuring there is always enough water in the rivers to protect fish and plant life factors into how both schemes operate with the landscape.

Working with the wildlife, weather and surrounding environment of the two rivers have always been a part of running the Lanark and Galloway schemes. Their continued role in the region’s electricity system highlights the relevancy of small-scale hydropower, even as demand for electricity grows.

Capacity Market agreements for existing assets and review of coal generation

Drax's Kendoon Power Station, Galloway Hydro Scheme, Scotland

RNS Number : 6536B

T-3 Auction Provisional Results

Drax confirms that it has provisionally secured agreements to provide a total of 2,562MW of capacity (de-rated 2,333MW) from its existing gas, pumped storage and hydro assets(1). The agreements are for the delivery period October 2022 to September 2023, at a price of £6.44/kW(2) and are worth £15 million in that period. These are in addition to existing agreements which extend to September 2022.

Drax did not accept agreements for its two coal units(3) at Drax Power Station or the small Combined Cycle Gas Turbine (CCGT) at Blackburn Mill(4) and will now assess options for these assets, alongside discussions with National Grid, Ofgem and the UK Government.

A new-build CCGT at Damhead Creek and four new-build Open Cycle Gas Turbine projects participated in the auction but exited above the clearing price and did not accept agreements.

T-4 Auction

Drax has prequalified its existing assets(5) and options for the development of new gas generation to participate in the T-4 auction, which takes place in March 2020. The auction covers the delivery period from October 2023.

CCGTs at Drax Power Station

Following confirmation that a Judicial Review will now proceed against the Government, regarding the decision to grant planning approval for new CCGTs at Drax Power Station, Drax does not intend to take a Capacity Market agreement in the forthcoming T-4 auction. This project will not participate in future Capacity Market auctions until the outcome of the Judicial Review is known.


Drax Investor Relations
Mark Strafford
+44 (0) 7730 763 949


Drax External Communications
Matt Willey
+44 (0) 0771 137 6087

Photo caption: Drax’s Kendoon Power Station, Galloway Hydro Scheme, Scotland

Website: www.drax.com/uk

A brief history of Scottish hydropower

The Clatteringshaws Dam in the Galloway Forest Park in south west Scotland. Built by Sir Alexander Gibb & Partners in 1932-38, it is on the south west

Over the last century, Scottish hydro power has played a major part in the country’s energy make up. While today it might trail behind wind, solar and biomass as a source of renewable electricity in Great Britain, it played a vital role in connecting vast swathes of rural Scotland to the power grid – some of which had no electricity as late as the 1960s. And all by making use of two plentiful Scottish resources: water and mountains.

But the road to hydro adoption has been varied and difficult, travelled on by brave death-defying construction workers, ingenious engineers and the inspirational leadership of a Scottish politician.

To trace where the history of Scottish hydropower began, we need to go back to the end of the 19th Century and to the banks of Loch Ness.

Loch Ness, Scottish Highlands

Loch Ness, Scottish Highlands

From abbeys to aluminium 

It was on the shores of Loch Ness that one of the first known hydro-electric schemes was built at the Fort Augustus Benedictine abbey. The scheme provided power to the monks living there as well as 800 village residents – though legend has it that their lights went dim every time the monks played their organ.

However, it was the British Aluminium Company, formed in 1894, that first realised the huge potential of Scotland’s steep mountains, lochs and reliably heavy rainfall to generate substantial amounts of hydro power. In need of a reliable source of electricity to help turn raw bauxite into aluminium, the firm established a hydro-electric plant and smelting works at Foyers and Loch Ness. Several similar schemes to support the aluminium industry soon appeared around the country.

But it took another 20 years for the first major hydro-power project to supply electricity to the public to emerge.

In 1926, the Clyde Valley Electrical Power Co. opened the Lanark Hydro Electric Scheme, which used energy from the River Clyde’s flow to create power. Now owned by Drax, it still has a generation capacity of 17 MW – enough to supply more than 15,000 homes.

River Clyde, Lanark

It was quickly followed by power stations at Rannoch and Tummel in the Grampian mountains and, in 1935, by what became a highly influential scheme in the history of Scottish hydro power at Galloway.

Drawing enough energy from local rivers to support five generating power stations, the project was the largest run-of-the-river scheme ever created. Architecturally, it also set the tone for later projects with stylised dams and modernist turbine halls.

A fairer share of power for the Highlands

The Galloway scheme supplied energy to a wide area, too, including parts of the central Highlands. Scottish Labour MP Tom Johnston, a staunch socialist and Scottish patriot saw how this new power source could provide massive benefits to northern communities. In the early 1940s, only an estimated one in six Scottish farms and one in a hundred small land crofts had electricity.

In 1941, Johnston became Scotland’s Minister for State with a vision, as he put it, to create “large-scale reforms that might mean Scotia Resurgent”. Expanding hydro power was a priority.

Tom Johnston MP

Two years later, he formed the North of Scotland Hydro-Electric Board (NSHEB). Its aim was to create several new schemes, including at Tummel and Loch Sloy, that would supply the national grid and bring electricity to more rural Scottish areas.

The projects were met with fierce opposition from landowners and local pressure groups who feared new dams and power stations would ruin the countryside and bring unwelcome industrialisation.

Public enquiries followed, but the board’s promises that the developments would be sensitive to the environment and bring cheap electricity in areas such as the Isle of Skye and Loch Ewe eventually won the day.

Thousands of local men, as well as German and Italian former prisoners of war, were drafted in to work on the projects.

Among the most courageous were workers known as ’Tunnel Tigers’ who blasted away rock using handheld drills and gelignite to create water channels and underground chambers, including at Drax’s Cruachan pumped storage hydro station.

Deaths caused by everything from blast injuries to fires were common. The men also had to cope with incessant rain and cold, and were housed in bleak military-style camps. With little to do in their spare time, besides drink, fights would break out regularly.

But the financial rewards were enormous, with wages up to ten times higher than labourers employed on Highland estates could expect.

Glenlee penstocks

The future takes shape

The board’s first small projects were completed in 1948 at Morar and Nostie Bridge, supplying electricity to areas including parts of Wester Ross. Catherine Mackenzie, a local widow, performed the Morar opening ceremony, reportedly declaring: “Let light and power come to the crofts.”

Bigger schemes were plagued by problems. Conveyor belts had to be built to transport stone across 1.75 miles of moor during construction at Sloy, for instance, and there were frequent stone and timber shortages.

But Sloy eventually opened in 1950, the largest conventional hydro electrical power station in Great Britain with an installed capacity of 128 MW. It would be followed by major schemes at Glen Affric and Loch Shin.

By the mid Sixties, the Board had built 54 main power stations and 78 dams. Northern Scotland was now 90% connected to the national grid. Hydro Board shops began popping up on high streets, selling appliances and collecting bill payments.

Tom Johnston died in 1965, aged 83. The Provost of Inverness declared: “No words can say how grateful we are.”

Cruachan Power Station

Loch Awe beside Cruachan Power Station

That same year, the world’s then largest reversible pumped storage power station opened at Cruachan. During times of low electricity demand, its turbines pump water from Loch Awe to the reservoir above. When demand rises, the turbines reverse, and water flows down to generate power. A similar scheme opened at Foyes in 1974.

Glendoe, near Loch Ness, was the most-recent major hydro scheme to be built. Opening in 2009, it has a generation capacity of 100 MW.

There are plans for a pumped storage scheme at Coire Glas, with a storage capacity of 30 GWh– more than doubling Great Britain’s current total pumped storage capacity. Drax’s Cruachan Power Station could also be expanded.

In recent years, however, the real growth has been in smaller hydro-electric schemes that may power just one or a handful of properties – with more than 100 MW of such generation capacity installed in the Highlands since 2006.

Boosting the environment and economy

Scotland now provides 85% of Great Britain’s hydro-electric resource, with a total generation capacity of 1,500 MW. Improved power supplies have attracted more industry to the Highlands, without seriously altering its character. And access roads created during hydro-power schemes’ construction have opened up remote areas to tourism.

For many, the dams built by NSHEB are among the greatest construction achievements in post-war Europe and remain an essential part of Great Britain’s attempts to move towards a low-carbon energy future.

The different ways water powers the world

If the spectacular Roman aqueducts that still dot the landscape of Europe tell us anything, it’s that hydraulic engineering is nothing new. For thousands of years water power has been used to grind wheat, saw wood, and even tell the time.

Craigside in Northumberland

By the 19th century, water was able to go beyond performing rudimentary mechanical tasks and generate electricity directly. Cragside in Northumberland, England  became the first house powered entirely by hydroelectricity in 1878. By 1881, the whole town of Niagara Falls on the US-Canada border was being powered by the force of its eponymous river and waterfall.

Hydropower has many advantages: it’s predictable, consistent, often zero or low carbon and it can provide a range of ancillary services to power transmission systems. In Great Britain, there is 1.7 gigawatts (GW) of installed hydropower and another 2.8 GW of pumped hydro storage capacity, but it remains a small part of the overall electricity mix. In the fourth quarter of 2018, the 65% of British hydropower that is connected to the national grid accounted for less than one per cent electricity generation or 545,600 megawatt hours (MWh). By contrast, wind accounted for 14% of total generation that quarter (almost 9.5 million MWh).

While hydropower projects can be expensive to construct, operational and maintenance costs are relatively low and they can run for an extremely long time – the Lanark Hydro Electric Scheme in Scotland, which Drax recently acquired, has been producing power since 1927.

Today, hydropower installations are found at all scales, all around the world. But the term hydropower covers many different types of facility. These are some of the ways water is used to generate electricity.

Impoundment power plants

The simplest and most recognisable form of hydropower, impoundment facilities, work by creating a reservoir of trapped water behind a dam that is then selectively released, the water flows through a turbine, spinning it, which in turn activates a generator to produce electricity.

From the Hoover Dam on the Nevada-Arizona border, to the Three Gorges Dam in China – the world’s largest power station of any type, with a generating capacity of 22.5 GW – impoundment dams are some of the most iconic structures in modern engineering.

Three Gorges Dam, China

As well as having the potential to provide large quantities of baseload power, they can react extremely quickly to grid demands – just by opening or closing their floodgates as the power system operator requires.

Run-of-river generation

Rather than storing and releasing power from behind a dam, run-of-the-river generators channel off part of a river and use its natural flow to generate power.

Tongland Power Station, Galloway Hydro Scheme

Because it doesn’t require large dams or reservoirs, run-of-river can be less environmentally disruptive, as there is not always a need for large scale construction and flooding is less common.

Stonebyres Power Station, Lanark Hydro Scheme

While run-of-river facilities tend to be smaller and less flexible than impoundment, they still have significant generating potential – the Jirau hydro-electric power plant on the Madeira river in Brazil has a generating capacity of 3.7 GW.

Pumped storage 

Water can also be good for storing energy that can then be converted to electricity. Pumped hydro storage facilities operate by pumping water uphill to a reservoir when electricity is cheap or plentiful, then letting it flow back downhill through tunnels to a series of turbines that activate generators to generate electricity (in the same way as an impoundment dam) when electricity is in high demand.

Dam and reservoir, Cruachan Power Station

Their ability to both produce and absorb electricity makes them a vital part of electricity networks, playing the role of energy storage systems. In fact, a massive 97% of all global grid storage capacity is in the form of pumped hydro. Their function as giant batteries will only become more important as intermittent renewable sources like wind and solar become more prevalent in the energy mix.

Outlet and loch, Cruachan Power Station.

So too will their ability to ramp up generation very quickly. Drax’s recently acquired Cruachan Power Station in Scotland can go from zero to 100 MW or more in less than 30 seconds when generation is called upon – for example, when there is a sudden spike in demand.   

Tidal range generation

Swansea Bay

The sea is also an enormous source of potential hydropower. Tidal range generation facilities exploit the movement of water levels between and high and low tide to generate electricity. Tidal dams trap water in bays or estuaries at high tide, creating lagoons. The dam then releases the water as the rest of the tide lowers, allowing it to pass through turbines, generating power.

There are limitations – like wind and solar’s dependence on the wind blowing and the level of sunlight, operators can’t control when tides go in or out. But its vast generating potential means that it could be a valuable source of baseload power if it were to be deployed more widely.

Great Britain in particular has major opportunities for tidal generation. The Severn Estuary between England and Wales has the second highest tidal range in the world (15 metres), and a barrage built across the estuary could have a generating capacity of up to 8.6 GW – enough to meet 6% of the Britain’s total electricity demands. Some environmental groups worry about the impact such projects could have on wildlife.

Due to the level of public funding required, the government rejected that plan in 2010, in favour of pursuing its nuclear policy. A second attempt at securing a government-backed investment contract, known as a CfD, for a smaller 320 MW ‘pathfinder’ project in Swansea Bay was also rejected, in 2018. The Welsh government is however supportive of the project, which already has planning permission.

Tidal stream generation

Rather than building a dam, tidal stream generators work like underwater wind turbines. Sturdy propellers or hydrofoils (wing-like blades which oscillate up and down rather than spinning around) are positioned underwater to transform the energy of tidal streams into electricity.

While tidal streams move far slower than wind, the high density of water compared to air means that more power is generated, even at much lower velocities.

Not reliant on large physical structures, tidal stream generators are a relatively cheap form of hydropower to deploy, and make a much smaller impact on their environment than tidal barrages.

Wave generation

Unlike tidal power, which is generated by the gravitational effects of the sun and moon on the Earth’s oceans, wave power ultimately comes from the winds that whip up the ocean’s surface.

There are a number of different methods that turn waves into generation, including funnelling waves into a tube floating on the surface of the water that contains electricity-generating turbines, or by using the vertical bobbing movement of a tethered buoy to pull and spin a fixed generator.

An electricity-generating buoy awaiting installation in Spain

Wave power has yet to be widely implemented, but it has significant potential. It’s estimated that the waves off the coasts of the USA could have provided 66% of the country’s electricity generation needs in 2017 alone. Effectively commercialising wave power could provide another vital tool in developing a sustainable energy landscape for the coming future.

Tidal and wave power generation are less established generation technologies than their land-based cousins but they hold huge potential in delivering more sources of reliable, zero emissions electricity for energy systems in coastal locations around the world.