Scottish Water has completed construction on a pioneering new type of hydro energy generation scheme at a reservoir in East Lothian, believed to be the first of its kind in Europe.

The £3 million scheme, at Whiteadder Reservoir, is expected to offset almost a third of the energy used by one of East Lothian’s largest pumping stations, named Hungry Snout, which takes around 32 millions litres of water per day to Castle Moffat Water Treatment Works before it goes on to supply most of the East Lothian region with drinking water.

The project allows green energy to be generated whilst also accurately controlling the level of the reservoir during seasonal fluctuations in weather.

Through the use of siphon technology, water is drawn up through the intake and over the top of the dam before running down through the siphon, through the hydro turbine, and back to the natural environment.

The project has been led by Scottish Water Horizons, the public utility’s commercial subsidiary, and delivered by renewable energy specialists Emtec Energy.

Acting Net Zero and Energy Secretary Gillian Martin said:

“This is a very welcome milestone in green energy and Scotland’s goal to reach net zero emissions by 2045. Scottish Water’s £3 million investment in this innovative technology, the first of its kind in Europe, is maximising the value of our water resources, reducing emissions and delivering benefits to customers by reducing costs which can be re-invested.

“Further investment in innovative technology will be required to adapt to the challenges presented by climate change, ensuring our water supply is more resilient and our waterways cleaner.”

Photo: Whiteadder overflow - project allows green energy generation

whilst also accurately controlling reservoir level

Senior Project Manager at Scottish Water Horizons, Neil Beaumont, said:

“We are delighted to have completed construction of this exciting project which will produce enough green energy to meet 30% of the power needs of the Hungry Snout pumping station and reduce our reliance on drawing energy from the national grid.

“We also wanted to ensure our carbon footprint was as low as possible throughout the construction process, which is why we used divers and barges to sink the pipes under the water – this was a much less intrusive and carbon intensive way of installing the new infrastructure than more traditional methods.”

He added:

“The scheme will ensure that we are protecting the water levels of the reservoir via smart controls and sensors, so that we are never taking too much water in order to power the hydro turbine – the reservoir’s primary function is to provide water to customers.”

The investment at Whiteadder will significantly reduce the carbon emissions from the pumping station, saving approximately 111 tonnes of carbon each year.

It is expected to generate 0.82GWh of renewable energy per annum from the 199kW turbine.

Photo: Whiteadder hydro turbine and pumping station 

Scottish Water’s General Manager for Net Zero, Elise Cartmell, said:

“Scottish Water is always looking for opportunities to create renewable energy via our assets, and this scheme joins over 30 hydro turbines already installed at our sites around the country.

“In the coming year, this number is set to increase as work starts on further hydro power schemes - we are proud to be leading the sector with innovative projects such as these which lower the carbon footprint of the local water supply.

“As a business, we are fully committed to meeting our ambitious net zero emission targets, and will continue to ramp up our production of green energy as quickly as we can.”

Chris Clark, Managing Director of Emtec, said:

"Whiteadder has been an incredible project to be part of, and I want to commend everyone involved for their vision in bringing such an innovative concept to life here in Scotland. One of the key challenges in renewable energy is achieving effective grid connections, and this hydro scheme addresses that brilliantly.

"It enables us to achieve exceptional generation yields with a much smaller grid connection compared to other renewable technologies like solar and wind. This project stands as a testament to what can be achieved through forward-thinking solutions and strong collaboration."

Scottish Water has committed to meeting net zero total emissions across all its operational and investment activities by 2040.