PLANS have been unveiled to revamp a hydro power station on the banks of Loch Lomond as it marks its 80th anniversary.

Sloy Power Station – the first of its kind in Scotland and largest in the country - was first built in 1943 as part of the Hydro Electric Development (Scotland) Act.

It's now set to be converted from a conventional hydro plant to a 'pumped hydro storage facility' - with investment in the "high tens of millions of pounds".

While the final design still has to be approved, the plans in their current form will allow the facility to provide renewable energy for up to 160 hours non-stop - enough to power 90,000 homes for one week.

First Minister Humza Yousaf, who visited Loch Lomond on Monday, said: “Scotland has vast natural resources which have helped us to become world leaders in renewable energy.

“Facilities like the Sloy Power Station continue to play a significant role in energy supply, providing flexible services to the grid and help to ensure a continued, resilient and secure electricity supply, by helping to balance our intermittent renewable electricity generation.

“Hydro power was the country’s original source of renewable energy and it has the potential to play a significantly greater role in the transition to net zero.”

The design will be reviewed over the next few months, and later this year the public will be able to have their say during a public consultation with more details to follow.

As part of their plans for SSE Renewables has also proposed another pumped hydro storage project at Coire Glas as part of a potential investment of more than £1.5m in what could be Britain's biggest pumped hydro storage scheme in 40 years.

Director of SSE Renewables, Finlay McCutcheon, said: “We're delighted to announce new redevelopment plans for our landmark Sloy Power Station, especially as we mark the 80th Anniversary of Hydro Power's contribution to homegrown power supply in Scotland and Britain.

“In converting our existing Sloy conventional hydro power plant to a pumped hydro storage facility, we can provide the additional large-scale, long-duration electricity storage we need as part of the country's future energy mix.

“The development of pumping capability at Sloy also complements our development plans for our other pumped hydro storage project at Coire Glas.

“Taken together and if approved for delivery, Coire Glas and Sloy can treble Britain’s current flexible electricity storage capacity.”

SSE Renewables hopes a planning application will be ready for submission to the Scottish Government by late 2023 or early 2024.

The company aims to make a final investment decision on Sloy in late 2025, and to fully transform the storage scheme by 2028.