Balmoral, Queen Elizabeth’s Scottish estate, is to become the first in the Royal household to be self-sufficient in energy.

The queen, who set up an energy-saving committee at Buckingham Palace to look at how to reduce consumption, has installed a small hydroelectric plant at Balmoral that is selling electricity to the national grid.

Privately owned and funded by the queen, Balmoral is the only estate with a “comprehensive biodiversity” action plan.

At the center of the plan is the hydroelectricity plant, which was developed on the Gelder Burn — a stream in the estate forest. The stream runs into the River Dee, about a mile southwest of the castle, which flows from Lochnagar, the 3,800-foot mountain that dominates the estate.

The plant generates sufficient power for the queen’s residence and 1,000 private homes in the area.

A water-driven turbine was installed at the queen’s Highland retreat in the 1920s to provide electric light. In the 1950s it was used to power the estate sawmill. As the mill now lies idle, a generator was installed that allows the turbine to be connected to the national grid.

The queen, who is committed to being as environmentally friendly as possible, has registered Balmoral’s woodlands with the Forestry Stewardship Council, which supports sustainable forestry worldwide. Its farming practices are registered with the Soil Association, which promotes organic food and farming.

All organic waste generated on the estate is recycled, with 50 tons of it being turned into compost each year. Machinery on the estate is powered by bio-diesel and biodegradable lubricants and oils.

“Green champions” work in every department, while the team of royal protection officers has been encouraged to patrol the estate on bicycles and to use Range Rovers much less.

A spokesman for Buckingham Palace said: “Balmoral has always been our beacon in our green work. The Royal household is constantly looking at new ways of saving and supplying energy so as to remain as environmentally friendly as possible.”

The project manager of the hydroelectric plant, Alastair Gill, said: “The powerful year-round flow of water should generate about one megawatt of electricity and runs like a miniature version of the massive Scottish hydro plants that can produce 300MW of power. These initiatives have been welcomed by environmental campaigners.”

Prime Minister Brown and his wife, Sarah, will make their annual trip to stay with the Queen and Duke of Edinburgh at the estate this weekend.