In what is a first for the Royal Household and largest of its kind in the South of England, consent has been granted to construct a hydroelectric scheme on the River Thames to power around a third of Windsor Castle.

The £1 million, 200kilowatt Romney Weir Hydro Scheme will be located next to Romney Island between Windsor and Eton in Berkshire.

The project, consisting of 4 turbines submerged in only 2 of the 10 bays that make up the weir, will be constructed by npower renewables. As the scheme is underwater and incorporated into the existing weir structure it will be virtually invisible and silent, having little effect on the surrounding area.

Alastair Gill, Hydro Development Manager for npower renewables, said, "This is great news. We have worked hard on the project to get it to this stage and its fantastic to receive the go-ahead. As well as being carefully designed to fit into the surroundings, by using the existing weir, the project will have little impact on the ecology, navigation and marine life of the river."

Mr Gill went onto say "With the weir shown to be more than adequate to cope with the flow of water along this stretch of the Thames, the hydro scheme will also have no effect on flood control measures."

A Spokesperson from the Royal Household said, "The Royal Household has an on-going policy of introducing and maintaining energy-efficient practices wherever possible, and sees consent of the Romney Weir Hydro Scheme as a major contribution towards these practice."

Tim Reeder, climate change regional project manager at the Environment Agency said, "We are always supportive of initiatives which can help reduce the impacts of climate change and have taken account of their local environment. The Environment Agency are keen to further investigate opportunities for hydropower, and are pleased to see this project finally come to fruition".

The next step is to run a feasibility study to better understand how to build the scheme. All being well construction is expected to begin next year, with Windsor Castle due to receive green electricity before the end of 2006.