Planning permission has been granted for Castle House, the first residential high-rise with building-integrated wind turbines. The 43-storey tower, which will be completed in London's Elephant and Castle in late 2009, will have three 9 m diameter wind turbines at its top in cowlings purpose designed to maximise wind velocities. These will provide enough electricity to light the entire building and are complemented by using small scale CHP. It is claimed that energy costs per apartment will be up to 40% less than typical UK housing.

The project is a joint venture between Multiplex and Espalier; architect is Hamilton Associates; multidisciplinary engineering consultant is WSP.