LONDON A technology to bury underground the greenhouse gas emissions produced from burning coal must be ready for global deployment by 2017-2019, U.S. energy secretary Steven Chu said on Monday.
Coal is the world's single biggest source of carbon emissions, at 40 percent. Other sources included burning oil and natural gas, and deforestation and the production of cement.
Chu was optimistic about the prospects for carbon capture and storage (CCS), even though no commercial-scale plant is being built yet anywhere. He said that the United States could have 10 demonstration plants online by 2016.
Most analysts do not expect the technology to be widely available before 2020 at the earliest.
"I believe we must make it our goal to advance carbon capture and storage technology to the point where widespread, affordable deployment can begin in eight to 10 years," Chu said in a letter to energy ministers gathered in London to promote global collaboration, and where Chu would speak on Monday.
Carbon capture technology is widely considered to be vital because high-carbon coal is one of the world's cheapest and most available sources of energy, making it unlikely the world can simply stop burning it.
The technology involves trapping carbon dioxide produced from burning the fossil fuel, for example using chemical solvents, and then separating the greenhouse gas and piping it underground for storage in depleted oil wells or acquifers.
But CCS adds about $1 billion to the capital cost of a coal plant and sacrifices about a quarter of energy output, making government support essential for initial deployment at a time when public finances are stretched.
The United States is investing more than $4 billion in the technology, to be matched by $7 billion from the private sector.
The European Union has a target to deploy up to 12 pilot plants by 2015, but few if any would be operational by then, analysts say, because of lead times to make cash available, win planning permission and build the plants.
Chu said his target was ambitious. "It will require an aggressive global effort, harnessing the scientific talent and resources of governments as well as industry," he said.
Some green groups argue uncertainty over CCS technology, and the short time-frame to curb greenhouse gas emissions, means the world should instead devote effort to deploying low-carbon fossil fuel alternatives such as wind and solar power.
The International Energy Agency said last week that global carbon emissions must stop rising before 2020 for the world to avoid more dangerous climate change.
At a global meeting in Copenhagen in December countries will try and agree a new climate pact to replace the Kyoto Protocol from 2013 and this week's London meeting aimed to define inclusion of CCS in that deal.
(Reporting by Gerard Wynn, Editing by Keiron Henderson)