The Anonymous Widower

Repurposing The Great Glen Hydro-Electric Scheme

The Great Glen 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 six individual power stations; Ceannacroc, Livishie, Glenmoriston, Quoich, Invergarry and Mucomir.
  • There are five dams; Cluanie, Loyne, Dundreggan, Quoich and Invergarry.

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.

  • Ceannacroc – 20 MW
  • Livishie – 15 MW
  • Glenmoriston- 37 MW
  • Quoich – 18 MW
  • Invergarry – 20 MW
  • Mucomir – 1.7 MW

This gives a total power of 112.7 MW.

This Google Map shows the same area as the SSE Renewables Map.


  1. Loch Quoich is in the South-West corner.
  2. To the East of Loch Quoitch is Loch Garry and to the North-East is Loch Loyne.
  3. Loch Cluanie is to the North.
  4. Invermoriston is in the North-East corner.

The scheme also includes three underground power stations and several miles of tunnels.

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 Great Glen scheme.

  • Invergarry – 22 GWh
  • Glenmoriston- 41 GWh
  • Quoich – 27 GWh

It would appear that based on research from Strathclyde University, that the Great Glen scheme could support up to 90 GWh of pumped storage.

Water Flows In The Great Glen Scheme

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


  • Loch Quoitch to Loch Garry via Quoitch power station.
  • Loch Garry to Loch Oich via Invergarry power station.
  • Loch Loyne to Loch Dundreggan via River Moriston.
  • Loch Cluanie to Loch Dundreggan via Ceannacroc power station and River Moriston.
  • Loch Dundreggan to Loch Ness via Glenmoriston power station.

All the water eventually flows into the sea at Inverness.

Refurbishing And Repurposing The Great Glen Scheme

Perhaps as the power stations are now over fifty years old, one simple way to increase the generating capacity of the Great Glen 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 Great Glen Scheme

I would assume that the water to pump uphill at night or when there is a surplus of electricity will come from Loch Oich or Loch Ness.

Some power stations like Glenmoriston and Invergarry might be updated to both generate electricity or pump water up hill, as is required.


There would appear to be up to three schemes, that could  each add around 30 GWh of pumped storage.

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

February 20, 2022 - Posted by | Energy, Energy Storage | , , , , , , ,

1 Comment »

  1. […] analysis in Repurposing The Great Glen Hydro-Electric Scheme, showed the […]

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

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