Branson offers £10m to the person who can prevent the climate change crisis

Sir Richard Branson is raising his game as "saviour of the planet" by announcing a multimillion-pound prize for the best way of removing thousands of tons of carbon dioxide from the atmosphere.

The prize - expected to be in the range of £10m - will go to the originator of the most convincing invention for actively absorbing and storing the principal man-made gas in the atmosphere responsible for global warming.

Sir Richard has drawn up a distinguished panel of judges to oversee the prize including James Lovelock, the inventor of the Gaia theory; James Hansen, the Nasa researcher who first warned the US government of climate change, and Tim Flannery, the Australian zoologist and explorer.

The competition is based on the idea of the $10m X-prize for the first privately-built, reusable aircraft that could fly into "space" - defined as 100km above ground - twice in one week. The X-prize was awarded in 2004.

The irony of basing an environment prize for absorbing carbon dioxide on a prize for releasing the gas in the fastest way possible will not be lost on many environmentalists who want to curb the unnecessary use of fossil fuel rather than relying on untried and unproven technological fixes for global warming.

Sir Richard is also expected to come under fire for setting up a company, Virgin Galactica, that intends to use the aircraft technology that won the X-prize to build up a space tourism industry where individual tickets for a 90-second ride in space will cost £100,000 each - as well as burning thousands of gallons of rocket fuel.

Details of Sir Richard's new prize will be released today at a press conference to be held at his exclusive "urban oasis", the Kensington Roof Gardens in London. He will be joined by Al Gore, the former American vice-president, and Sir Crispin Tickell, the former British ambassador to the United Nations and distinguished environmental campaigner.

None of the participants was able to comment on the prize yesterday because of the strict confidentiality imposed on the event by Sir Richard's public relations team, which is keen to generate as much beneficial publicity for the Virgin brand as possible.

It is known that Al Gore visited Sir Richard's London house last summer where the two exchanged views on the environmental challenge posed by climate change - a challenge made worse by the fast growing increase in airline traffic.

Last September, Sir Richard announced at the Clinton Global Initiative in New York that he would invest all his profits from his five airlines and train companies - which he estimated to be $3bn over 10 years - into researching ways of developing energy sources that do not contribute to global warming.

"Our generation has inherited an incredibly beautiful world from our parents and they from their parents. It is in our hands whether our children and their children inherit the same world. We must not be the generation responsible for irreversibly damaging the environment," Sir Richard said at the time.

However, critics subsequently pointed out that Sir Richard was not making a philanthropic donation along the lines of multibillionaires such as Bill Gates and Warren Buffet, but intending to divert his profits into commercial ventures to produce renewable energy. Others pointed out the $3bn donation he promised looked higher than he could feasibly raise from his company's profits alone.

Nevertheless, sources close to the new prize said Sir Richard was serious about encouraging ideas that could bring down the concentration of carbon dioxide in the atmosphere, or at least slow down the rate of growth over the coming century.

The technology is called "carbon capture and sequestration" and it involves absorbing carbon dioxide gas by, for example, chemically combining it with minerals to produce an inert substance that could then be buried either underground or in deep-sea deposits where it would remain undisturbed for 1,000 years or more. The idea is already being used to develop ways of capturing carbon dioxide from power stations, but Sir Richard's prize will focus on stimulating ways of capturing carbon dioxide from the atmosphere - a much harder task because the gas will be in lower concentrations compared to the emissions from a power station chimney.

Sir Richard is known to have compared the idea of his prize to that established in the 17th Century for the first person to devise a method of estimating longitude accurately, won by John Harrison, a self-taught Yorkshire clockmaker.