The Anonymous Widower

Repurposing The Breadalbane Hydro-Electric Scheme

The Breadalbane hydro-electric scheme was built in the 1950s and early 1960s, by the North of Scotland Hydroelectric Board.

  • The scheme is now owned by SSE Renewables and has a page on their web site.
  • There are seven individual power stations; Lubreoch, Cashlie, Lochay, Finlarig, Lednock, St Fillans and Dalchonzie.
  • There are five dams; Lawers, Breaclaich, Lednock, Lubreoch and Giorra.

This map from the SSE Renewables web site shows the layout of the dams and power stations.

The sizes of the power stations in the scheme are as follows.

  • Lubreoch – 4 MW
  • Cashlie – 11 MW
  • Lochay – 45 MW
  • Finlarig – 16.5 MW
  • Lednock – 3 MW
  • St Fillans – 16.8 MW
  • Dalchonzie – 4 MW

This gives a total power of 100.3 MW.

This Google Map shows Loch Tay.


  1. Finlarig. where there is a power station, with a capacity of 16.5 MW.
  2. Ben Lawers dam, is to the West of Ben Lawers and is marked by a blue arrow.
  3. The biggest power station in the scheme is Lochay power station, which has a capacity of 45 MW.
  4. Lochay power station is to the West of Finlarig power station and both appear to be fed from Ben Lawers dam and others to the North.

This Google Map shows Loch Earn.


  1. Loch Earn is South of Loch Tay
  2. The red arrow indicates Dalchonzie  power station.
  3. Dalchonzie  power station has a generating capacity of only 4 MW.

This Google Map shows the location of Loch Lednoch between Loch Tay and Loch Earn.

Note that Lednoch has the 3 MW Lednoch power station at its Northern end.

This map shows to the West of Ben Lawers.

The red arrow indicate the rough location of the 11 MW Cashlie power station.

Is The Breadalbane Scheme Complete?

Looking at the dates of power station construction, I wonder if the dam builders concentrated in the early 1960s on the construction of Cruachan pumped storage station, which was constructed between 1959 and 1965.

Also to me, the Breadalbane scheme seems to have a lot of power stations and tunnels for just over 100 MW.

  • At Rannoch, there is a 44 MW power station on the shores of Loch Rannoch, that was built in 1930.
  • At Sloy there is a 152.5 MW power station on the shores of Loch Lomond, that was built in 1950.

I would have thought that a progression from Sloy, would have seen a large power station built on the shores of Loch Tay, whereas Lochay power station is only 44 MW.

This Google Map shows Lochan Breaclaich, which is a lake created by the construction of Breaclaich dam.

Lochan Breaclaich is marked by the red arrow and it is Loch Tay at the top of the map.

This page on the Canmore web site gives these details of Lochan Breaclaich and its dam.

Breaclaich dam is designed to prevent Loch Breachlaich and a number of other intakes from discharging into the Loch Tay catchment. A tunnel intake gatehouse is upstream of the dam and takes water via tunnel and pipeway through to Lednock power station.

The SSE map shows this tunnel to the North-Western end of Loch Lednoch, where the Lednoch power station is located.

It seems a lot of work was done to feed the power station, which has a capacity of just 3 MW.

Was it originally intended that Lochan Breaclaich would have fed a large power station on the Southern shore of Loch Tay?

Strathclyde University And Pumped Storage Power For Scotland

This page on the Strathclyde University gives a list of the pumped storage potential for Scottish hydrogen-electric dams and power stations.

These figures are given for the dams and lochs in the Breadalbane scheme.

  • Ben Lawers – 12 GWh

It would appear that based on research from Strathclyde University, that the Breadalbane scheme could support 12 GWh of pumped storage.

Could this be augmented by a pumped-storage scheme from the Southern shore of Loch Tay to Lochan Breaclaich?

  • Lochan Breaclaich is at an altitude of 443 metres.
  • Loch Tay is at an altitude of 106 metres.
  • Foyers pumped storage has a capacity of 300 MW and a head of 179 metres.

If a 12 GWh pumped storage system can be built on the North side of Loch Tay, I can’t see why with a head of 337 metres, one can’t be built on the South side of the Loch.

Was this the original plan?

Water Flows In The Breadalbane Scheme

Looking at the SSE Renewables map of the Great Glen scheme, water flows appear to be as follows.

  • Loch an Daimh to Stronuich Reservoir via Cashlie power station
  • Loch Lyon to Stronuich Reservoir via Lubreoch power station
  • Stronuich Reservoir to Lochay power station
  • Loch Ben Lawers to Finlarig power station
  • Lochan Breaclaich to Loch Lednock via Lednoch power station
  • Loch Lednock to Loch Earn via St. Fillans power station
  • Loch Earn to Dalchonzie  power station

It seems to be an expensive scheme with lots of tunnels and an underground power station at St. Fillans.

Refurbishing And Repurposing The Breadalbane Scheme

Perhaps as the power stations are now over fifty years old, one simple way to increase the generating capacity of the Breadalbane scheme, might be to selectively replace the turbines, with modern turbines, that can generate electricity more efficiently.

I suspect that SSE Renewables have an ongoing program of improvements and replacements for all of their hydro-electric stations in Scotland. Some turbines at Sloy power station have already been replaced with larger ones.

Adding Pumped Storage To The Breadalbane Scheme

In this list of Scotland’s lochs on Wikipedia, there is a short list of the largest and deepest lochs.

  • The first five are Loch Ness, Loch Lomond, Loch Morar, Loch Tay and Loch Awe.
  • Loch Ness has the Foyers pumped-storage scheme and others are in development.
  • Loch Awe has the Cruachan pumped-storage scheme.
  • Loch Lomond has the Sloy pumped-storage scheme in development.
  • Loch Morar is used in the Lochaber hydro-electric scheme.

It seems to me, that Loch Tay could support some pumped-storage, just because of its size.

Strathclyde University have identified that Ben Lawers can support 12 GWh on the North side of Loch Tay.

Could a scheme involving Lochan Breaclaich add a similar amount of pumped-storage  on the South side of Loch Tay?

I also suspect there are possibilities for adding pumped-storage to and from Stronuich Reservoir.


I believe that Breadalbane is an incomplete scheme and that pumped-storage could convert this scheme into a much more powerful and larger scheme.

There would appear to be two schemes, that could  each add around 12 GWh of pumped storage.

One advantage is that the waters of Loch Tay can be used for the lower reservoir.


February 27, 2022 - Posted by | Energy, Energy Storage | , , , , , ,


  1. Strathclyde University web link is v.interesting and astonishing that repurposed existing schemes could provide c500GWh is not be sneered at. Environmentalists would no doubt object but without more storage net zero is just a pipe dream.

    Comment by Nicholas Lewis | February 27, 2022 | Reply

  2. I feel the interesting scheme is ILI Group’s Red John scheme. It may be only 450 MW/2.8 GWh, but it has got planning permission and I suspect a company in the City is funding it. After all if the City will fund Gore Street and Gresham House Energy Storage Funds, what’s the difference in funding something bigger.

    But the environmental lobbies don’t seem to have been against it. But this one is next door to the Foyers scheme which was created nearly fifty years ago.

    SSE have also got planning for the massive Coire Glas scheme, which is 30 GWh.

    Comment by AnonW | February 27, 2022 | Reply

  3. Amazing how advanced Scotland is with this.

    Surely there are equivalent schemes in England?

    H x

    Comment by askthevetnurse | March 2, 2022 | Reply

    • Scotland has mountains, lochs and rain.

      But some of the lochs are deep, so are ideal for pumped storage.

      A lot of the groundwork was done years ago by pioneers at British Aluminium and the North of Scotland Hydro-Electric Board.

      We need energy storage in England and engineers are working on innovative ideas, but we don’t have any places for pumped storage.

      One of my favourites is a company called RheEnergise, that instead of water uses a heavy water-based environmentally-friendly fluid, which has a specific gravity of 2.5. This means you can build pumped storage systems inside hills.

      Comment by AnonW | March 2, 2022 | Reply

  4. […] analysis in Repurposing The Breadalbane Hydro-Electric Scheme, showed the […]

    Pingback by Scotland’s Energy Storage « The Anonymous Widower | March 2, 2022 | Reply

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