The Rumbling Bridge hydro scheme is located near Rumbling Bridge village, Perth & Kinross, Scotland.
For a larger map including schematic of the site click here
Development of the Hydro Plant
The project was successfully tested for feasibility by Green Highland Renewables in January 2014 and has since been granted the necessary consents and licenses. Chris Pasteur, an experienced hydro developer with Cairnyhill Ltd was contracted by Rumbling Bridge Community Hydro Society in September 2015 to design the scheme and manage the installation.
SSE Power Distribution has provided a grid connection offer to Rumbling Bridge. A deposit has been paid to secure this connection offer.
Detailed discussions with turbine manufacturer, Tinck are continuing for the supply and installation of 2 X 250kW Francis turbines with an alternative supplier lined up if necessary.
Balance of Plant
The Civil Engineering works comprise: access tracks from the site entrance to the locations of the Hydro Plant foundations and weir; design and installation of the civils, including any required reinforcing work and construction of the turbine house. This also includes the installation of on-site electrical ground works in preparation for the grid connection.
A tender has been issued to potential contractors for the Civil Engineering works. Based on initial tenders a preferred contractor has been selected for negotiations leading to a contract. The chosen contractors have considerable experience of building hydro projects of similar scope as required for Rumbling Bridge. Chris Pasteur of Cairnyhill will co-ordinate all contractors and be responsible for delivering the works programme
Operation of the Hydro Turbines
Hydro turbines are described by a theoretical rated output of power based on the optimum size of turbine, relative to the flow of water available in the river. In this case, if water at the intake were to flow at speeds in excess of 2.3 cubic meters per second, then the turbines will generate at a steady 500kW of power output.
The Hydro Turbines will benefit from a manufacturer’s warranty and there will be an operation and maintenance agreement. As the turbines age, mechanical parts may need replacing, however modern hydro turbines are normally extremely reliable.
Wallingford HydroSolutions Ltd, independent and experienced experts have carried out a hydrological assessment to calculate the potential flow that can be expected at the intake point of the river. The River Devon drains from a large upland catchment of 74.5 km2 in the Glendevon area of the Ochil hills. The catchment drains through five large reservoirs operated by Scottish Water. Financial Projections are based on an assessment of the long term Flow Duration Curve.