The company says the scheme to fit turbines in large water supply pipes will allow it to meet 10 per cent of its power needs, up from 5 per cent.
Around 20 sites are to be selected for the in-pipe hydro technology out of more than 30 identified as potentially suitable.
Ian McMillan, who is leading the building programme for Scottish Water’s capital investment and delivery division, said: “This is a key part of our Climate Change Strategy and will substantially reduce our carbon footprint. We’re very excited about technology that offers the dual benefits of improved service for our customers and reduced operating costs.”