Two Hydro Schemes on Arran

By Helen Ross – Chair, Arran Eco Savv, April 2022

• The two Hydro Schemes illustrated here, each generate 500kW electricity when at full power. This is enough to power approximately 400 homes per year or boil approximately 160 electric kettles constantly (one electric kettle uses a maximum 3kW of electricity whilst boiling).
• There are no emissions, other than those used in the construction.
• How can we build on these examples of good practise to generate electricity and contribute to the local economy with minimal impact on the environment on Arran?

1. Dougarie Hydro Scheme: River Allt Gobhlach, Pirnmill Isle of Arran

Water enters the scheme at the ‘Head’ that creates the water pressure. In other words, the height at which the river or supply source enters the hydro scheme. In this case at 190 metres ….










… and travels down pipes like these, hidden from view under the path.










The water is passed through a Canyon Turbine, which generates the power sent to the National Grid via a cable at this pylon ……











The contractors were Mam Contracting


2. Glenkiln Hydro Project, Isle of Arran

Glenkiln Hydro signed the contract for the construction of their hydro electric scheme on Arran with local contractor, Murchie Sand & Gravel Ltd. This was not only beneficial from a logistics point of view but also intended to benefit the wider economy of Arran. Because the project had to be built during the winter months of 2017, there were many days when the conditions were absolutely atrocious, but the men worked 12 hours each day for seven days a week, months on end, together with the driving force from the women in the office. The development is up and running successfully and is pictured below.

Kenny Bone – Glenkiln Hydro in front of the Powerhouse:



Kenny Bone from Glenkiln Hydro with Green Island Programme Team members: Louise Logan – Arran Eco Savvy, Duncan Sinclair & Dan Ellis: Adler & Allan
Helen Ross Chair Eco Savvy with Kenny Bone from Glenkiln Hydro












Inside the Powerhouse ……
















More information and pictures of the construction can be found here: –

Photos courtesy of Aidan Nelson – Dougarie Scheme, & Helen Ross – Glenkiln Scheme