An almost £50 million refurbishment of SSE Renewables’ Tummel Bridge hydroelectric power station in the Highlands of Scotland is set to get underway, with construction work to commence in Spring 2022. This is the largest single investment SSE Renewables has made in the refurbishment of its existing hydro fleet in recent times.
Repowering of the power station is expected to extend its operational life by at least 40 years, meaning the hydro plant will be running in the power system of 2050 and will play a continuing role in harnessing hydropower for a net-zero future in Scotland and the UK.
The refurbishment works will help support the Scottish regional supply chain and local job creation, with the delivery of the works programme expected to support up to 65 construction roles at peak.
Located in the centre of the overall Tummel Valley Hydro Scheme cascade, Tummel Bridge Power Station was commissioned in 1933 and is one of the oldest hydro power plants in Scotland. The power station, which is housed within an iconic Category A listed structure, currently delivers around 140 GWh of renewable generation output each year. As well as generating its own power output, it plays an important strategic role in efficiently moving water onwards in the overall hydr-electric scheme to the Clunie and Pitlochry power stations.
Under the repowering programme, SSE Renewables will replace the existing two ‘Camel Back’ twin-runner, horizontal Francis hydro turbines at Tummel Bridge with new modern runner technology. This will result in increases to water flow, enabling an increase in the generation output at the plant from 34MW to 38MW, with a peak output of 40MW during optimum conditions.
The repowering works are expected to be completed in late 2023, coinciding with the hydro power plant’s 90th anniversary.
"I’m delighted we are demonstrating our commitment to our existing hydro fleet by making a significant investment of almost £50m to repower our Tummel Bridge Power Station," said Peter Diver, head of Hydro Operations at SSE. “By repowering the existing turbines with latest hydro technology we are able to make best use of the available water flow and head at the station to increase generation output and maintain our capability to reliably manage water flows through the Tummel cascade."
Voith Hydro has been appointed as lead Mechanical and Electrical (M&E) contractor for the project. Voith previously supported SSE Renewables in 2020 in successfully modernising the second machine of its Foyers pumped storage power station near Inverness, Scotland. Stantec is leading on Civil Design and has been supporting SSE Renewables on the refurbishment project since Autumn 2018.
Global Infrastructure has been appointed to undertake enabling works including site establishment, superstructure bracing work, and general site readiness. Global Infrastructure’s enabling contract is also expected to support a host of local and UK-based subcontractors.
Global Energy Group at Port of Nigg in Cromarty Firth has been appointed for Forebay Stoplog fabrication and Tailrace Gate modifications, while the contract for Corrosion Protection works on the penstocks, or water intake structures, has been awarded to Rosyth-based KAEFER.
The contract to modernise and upgrade the 88-year-old 120 tonne station crane has been awarded to Konecranes Demag UK at East Kilbride. McDonald Scaffolding from Invergordon has been appointed as scaffolding contractor.
In addition to investing in the repowering of existing operational schemes such as Tummel Bridge, SSE Renewables is also actively progressing the development of its consented 1.5GW Coire Glas pumped storage project in Scotland’s Great Glen. With 30GWh of storage potential, it would be the first large-scale pumped storage scheme to be developed in the UK for more than 30 years and would more than double Great Britain’s existing electricity storage capacity if constructed.