Sloy-Awe Hydro-Electric Power Scheme

Loch Sloy is a relatively small loch located to the west of Loch Lomond and around 800 ft above it. The engineer Edward MacColl was asked to look at the possibility of using it for a hydro-electric scheme in 1936, while working for the Central Electricity Board. However, rather than a conventional arrangement, he considered that it was suitable for a huge pumped-storage scheme, which would have been much larger than any of the existing schemes in Scotland. He called it a "reversible hydraulic station", which would pump water from Loch Lomond to Loch Sloy during the night, and use the water to generate electricity at times when the demand was highest. He envisaged eight turbines, with a…

The scheme was expected to be operational by 1947, but it soon became apparent that this was not achievable. Margaret Johnston, the wife of Tom Johnston, the architect of the 1943 Act, "cut the first sod" on 11 June 1945 using an 18-ton bulldozer, rather than the traditional polished spade, but activity soon stopped, due to an inability to find a workforce in the immediate post-war period. German prisoners-of-war were allocated to the job, and by the end of the year, there were 45 British men and 398 prisoners-of-war working on the scheme. They built access roads across the hills, camps for the workers, and railway facilities, including a bridge over the main pipelines for the West Highland…

On 18 February 1950, Sir Edward MacColl, who had only recently been knighted, switched on the first generator set at Sloy at 3:15 pm. Residents of Tarbet, further south on Loch Lomond, and at Arrochar on Loch Long, had been supplied with electricity from the temporary diesel generating station since April 1948, when Miss Mary MacFarlane, the oldest resident of the village, aged 96, had switched on the new supply. The official opening ceremony took place on 18 October 1950 and was performed by Queen Elizabeth. Despite the cold and wet weather, and the fact that guests had to wait around for a long time, MacColl had ensured they were not cold by installing an electric light bulb underneath…