Soham

Chinese hydropower lobbyists are calling for construction of the world's biggest hydro-electric project on the upper reaches of the Brahmaputra river as part of a huge expansion of renewable power in the Himalayas.

Zhang Boting, the deputy general secretary of the China Society for Hydropower Engineering, told the Guardian that a massive dam on the great bend of the Yarlung Tsangpo - the Tibetan name for the river - would benefit the world, despite the likely concerns of downstream nations, India and Bangladesh, which access water and power from the river.

Zhang said research had been carried out on the project, but no plan has been drawn up. But documents on the website of a government agency suggest a 38 gigawatt hydropower plant is under consideration that would be more than half as big again as the Three Gorges dam, with a capacity nearly half as large as the UK's national grid.

"This dam could save 200m tonnes of carbon each year. We should not waste the opportunity of the biggest carbon emission reduction project. For the sake of the entire world, all the water resources than can be developed should be developed." That CO2 saving would be over a third of the UK's entire emissions.

The mega-facility is among more than 28 dams on the river that are either planned, completed or under discussion by China, according to Tashi Tsering, a Tibetan scholar of environmental policy at the University of British Columbia.