Kirkthorpe Hydropower will be the largest hydro scheme in Yorkshire, and, once commissioned in November the £5.3m facility will have a 500kW capacity – producing around 2.3M.kWh per annum. This is enough renewable electricity to take around 800 homes off the grid.
The scheme comprises a 500kW axial turbine and is being developed on land owned by Wakefield Council on the River Calder 6.4km east of Wakefield. The project at Kirkthorpe is a complex shape as the water has to be channelled through the hydro scheme via a diversion around a weir and then back into the main flow channel.
The works at the site involved excavations up to 10.5m deep in a horse shoe shaped cofferdam and is an ongoing 50 week programme. The load on the lower frames in the deepest section of the cofferdam was 570kN/m, which is high for proprietary shoring equipment, Mabey Hire selected Supershaft Plus as the strongest proprietary brace on the market, which allowed maximum spacing of the cross struts.
The final temporary works designs satisfied the requirement to develop a cofferdam support solution that avoided the need for propping at higher level; this was a key early requirement in the design brief from Eric Wright. Mabey Hire worked in conjunction with Eric Wright and temporary works designer Pascoe Consulting proposing different alternatives regarding the construction sequence, so Eric Wright could evaluate the most cost-effective solution. Being involved at the early stage allowed Mabey Hire to be involved in evaluating possible solutions that could quickly be dismissed or progressed.
View aerial footage of the site here
