Nov. 10 (Bloomberg) -- The global economic crisis has opened “a relatively narrow window of opportunity” to halt the increase in greenhouse gases released by power plants, factories and cars through 2020, the International Energy Agency said.

Annual emissions from using energy may peak at 30.9 billion tons over the coming decade, assuming “radical and coordinated policy action across all regions,” the Paris-based IEA said today in its World Energy Outlook. The agency reiterated its Oct. 6 forecast that global energy use will decline this year for the first time since 1991 because of the recession.

“The financial crisis offers what may be a unique opportunity to take necessary steps as the political mood shifts,” the IEA said. “This saving will count for nothing if a robust deal is not reached in Copenhagen.”

Representatives from 192 countries will meet in the Danish capital next month to replace or extend the 1997 Kyoto Protocol. That may in fact take another year as negotiators hold back on pledges to slash emissions or pay financial aid to poor nations, officials said after talks last week in Barcelona. Yvo de Boer, the United Nations climate talks supervisor, said too little progress has been made to conclude a treaty in Copenhagen.

The 1997 treaty, whose initial phase runs for the five years ending in 2012, included caps on industrial nations requiring cuts of about 5 percent in greenhouse gases, which scientists blame for climate change, from 1990 levels.

The IEA estimated that the world will need to spend an additional $10.5 trillion to achieve the goal of limiting worldwide temperature increase to 2 degrees Celsius (3.6 Fahrenheit). About 45 percent of this additional investment will be focused on transportation, the IEA said.

Carbon prices would need to rise to $50 a metric ton by 2020 in industrialized nations, IEA Chief Economist Fatih Birol said today at a London briefing. Benchmark prices are about 13.86 euros ($21) a ton today, according to the European Climate Exchange in London.

To contact the reporters on this story: Mike Anderson in London at manderson34@bloomberg.net; Mathew Carr in London at m.carr@bloomberg.net

Last Updated: November 10, 2009 08:41 EST