The installation of an Archimedes screw hydro-electric turbine in the River Wandle at Morden Hall Park is now complete and is generating electricity. The screw, manufactured in the Netherlands, arrived at the park in July 2012. It was officially switched on by Simon Jenkins, Chairman of the National Trust, in the presence of Rt Hon Ed Davey, Secretary of State for Energy and Climate Change and MP for Kingston & Surbiton on 2 November. All the key turbine funders came to the event – Heritage Lottery Fund, City Bridge Trust and Thames Water – and seemed very happy with how their funding had been spent.
The turbine is an 8.5kW system and is designed to generate 59,000 kWh or electricity per year – enough to power about 16 average households. It will power the Old Stable Yard with spare electricity to sell back to the grid. Its life expectancy is 40+ years and it is expected to pay for itself in 25-30 years.
Fish can travel down the screw quite happily – it doesn’t harm them. The fish and eel passes beside the screw mean that they can travel upstream quite safely too, which they were previously prevented from doing by the weir.