The hydro scheme is a 75kW project at the island’s Forest Estate which commissioned the construction to take advantage of economic and environmental benefits that offered a regular income but with little disruption to surrounding land. Energy produced by the scheme allows 50kW to be sold directly to the grid and 25kW to be used for heat and electricity in the estate lodge.
Included in the project are an intake weir on the Allt Libhir at an elevation of 128 metres above sea level, a buried pipeline 1,280 metres long, and a small power house near the mouth of the stream. The turbine is a Tinck single jet Pelton operating under a head of 120 metres.
Working under contract with consulting engineer, Adrian Laycock, Fusion Marine fabricated the 1.28km of large diameter polyethylene piping required for the scheme at its coastal production base at Loch Creran. Fabrication work included the specialised Fusion welding process and fitting specially-designed brackets and caps.
Six 200-metre lengths of the completed plastic pipes were then towed more than 60 miles to Jura from the slipway at Barcaldine by the MV Felstad. The vessel also carried a full deck cargo of materials and other equipment needed for the installation.
The pipes were then moved ashore on to a beach close to the hydro site and up the hillside into position where Fusion Marine engineers carried out the final welding of the various sections using remote electrofusion jointing equipment. There was no access track to the intake, so a helicopter was used for placing concrete in the intake weir.
Stephen Divers, managing director of Fusion Marine, said: “The remote location of the site presented a real challenge for this project. However, for several years we have successfully taken advantage of our coastal location in Argyll for the sea-borne delivery of salmon pens to their final farm sites and this seemed the ideal solution for transporting the pipes to Jura.”
Large diameter polyethylene piping is ideal for small-scale hydro schemes as it is flexible and light which means the course of the pipe can closely follow the lie of the land.
Other local contractors involved in the construction project were Martin Boyle Contracting, McEachern Brothers, Andrew Bauld, and Kestrel Controls.
