With over 90 inches of rain failing on Ardtorish each year, Ardtornish Estate has taken the opportunity to create clean, green energy in a way which doesn’t damage the environment.
On the river Rannoch, the estate replaced their earlier 1996 ‘run of river’ hydro scheme with a cascade system of three independent hydro schemes. Two intakes divert additional, via a low-pressure aqueduct pipe into Loch Tearnait, which acts as a water storage reservoir. The loch is fed by both these new water intakes and the river and burns that flow into it naturally. The Tearnait hydro intake feeds this water into the 1000m long penstock which creates a 60m head (i.e. 60m pressure of water) at the new Tearnait power house at the eastern edge of Strath Shuardail.
Having produced up to 700 kW of electricity in that (the Tearnait) power house, the water returns to the river and fills Lochan Lùb an Arbhair. This new loch was created by the 2012 Rannoch Dam – probably the largest thing to be built in Morvern since Ardtornish House in 1884. The water flows from dam down another penstock, generating a 69.5m head and up to 1500 kW of output at the Rannoch Power House.
From there it re-enters the river, and few hundred metres downstream the water is impounded again. This time it enters a low-head pipe under the road, emerging again at the top of a mesmerising Archimedes Screw Turbine, which sits beside the river at Achranich. It uses the water a third time, before finally it is discharged into the river to flow the few remaining metres downstream and downhill to the sea.
The electricity is sold to the national grid, providing Ardtornish with the income it requires to help do the things they need to do, and consumers with a supply of green, clean energy.
During 2017, the Estate built a new hydro power station, the Socaich scheme, which catches water from several intakes on the Achranich hillside and diverts it into Lochan Lùb an Arbhair. Before flowing into the lochan, it goes through a Gilkes turbine, producing up to 325 kilowatts of power.
The extra flow into the lochan joins the other sources to flow through the Rannoch turbine, generating again. Then it enters the Archimedes screw turbine – so, like water passing through the Tearnait hydro scheme, each drop passing through the Socaich scheme is used three times before finally flowing to the sea.