* World needs 100 carbon capture projects by 2020
* More than 3,000 needed by 2050
* Carbon capture must be part of Copenhagen climate deal
(Adds closing comments from London conference)
By Daniel Fineren
LONDON, Oct 13 (Reuters) - The world needs to build 100 major projects for capturing and burying greenhouse gases by 2020 and thousands more by 2050 to help combat climate change, International Energy Agency chief Nobuo Tanaka said on Tuesday.
Energy ministers meeting in London said the world must start building by next year at least 20 commercial-scale pilot projects to test a technology which U.S. energy secretary Steven Chu said could solve "20 percent of the problem" to curb carbon.
The drive, mostly to capture emissions from coal-fired power stations, would cost $56 billion by 2020 alone, said Tanaka. Carbon capture funding could be a key part of a new U.N. climate treaty due to be agreed in Copenhagen in December.
"We will need 100 large scale projects by 2020, 850 by 2030 and 3,400 in 2050," Tanaka told the ministers at a carbon capture and storage (CCS) conference, adding that the rich world must take the lead but most projects must be in non-OECD countries by 2050.
A few industrial-scale projects are in operation, including in Norway, Canada and Algeria, but none tests all parts of the capture process. Heat-trapping carbon dioxide can be taken from the exhausts of a coal-fired power plant, for instance, then piped underground into porous rocks.
The IEA estimates that after the $56 billion investment in CCS globally from 2010-2020, a further $646 billion will be needed from 2021 to 2030, Tanaka told the Carbon Sequestration Leadership Forum.
U.N. studies have indicated that CCS could do more to limit greenhouse gas emissions this century than a shift to renewable energies such as wind or solar power. CCS has been limited by high costs.
"We call upon the delegates to the United Nations climate conference in Copenhagen to recognize the importance of CCS in mitigating climate change," said a closing statement of the 15 ministers, including those from the United States, Europe and China.
"The world’s biggest coal-using nations recognise we cannot continue with business as usual on coal," British Energy Secretary Ed Miliband said. "We need a mechanism which will at least provide the opportunity for developing countries to get help with financing some of the incremental costs of their projects."
A promise of big aid via technologies such as CCS could encourage developing nations led by China and India to sign up in Copenhagen for more action to limit rising emissions.
Talks on the new U.N. climate deal made little progress at a two-week session that ended in Bangkok last week, partly because of disputes between rich and poor nations about sharing out the burden of curbs on greenhouse gas emissions.
It is unclear if the U.S. Senate will pass laws before Copenhagen to cut national emissions, and recession is dampening willingness to act.
In Australia, a survey on Tuesday indicated that saving jobs was the top priority for voters. Fighting climate change fell to seventh, two years after Prime Minister Kevin Rudd was swept to power on a promise to tackle global warming.
The government said it was committed to an emissions trading scheme which, if defeated in November, could bring a snap election. "Our policy is not determined by polls," Climate Minister Penny Wong said of the survey.
So far, few nations have agreed to invest heavily in carbon capture technologies -- nations including the United States, Australia, Britain and China have projects.
Still, in a national budget on Tuesday, Norway said it would almost double funding of carbon capture research to $620 million next year. Norway has the oldest commercial carbon capture site, set up in 1996 at the Sleipner gas field in the North Sea. -- Additional reporting by Gerard Wynn