By Alister Doyle
BONN, Germany (Reuters) - The United States is leading a shift away from using coal among leading industrialized democracies, with Japan the main laggard in policies that will help to combat climate change, according to a study on Wednesday.
Behind the United States in the Group of Seven (G7) came France, Britain, Canada, Italy, Germany and Japan, the London-based E3G environmental think-tank said in a report issued during U.N. negotiations on a deal to slow global warming.
G7 nations agreed at a summit in Germany in June to aim for a decarbonization of the world economy this century to slow climate change. The study said it was the first to assess G7 performance on coal, the most polluting fossil fuel.
"The United States has the largest challenge given the scale of its existing coal use, but is making the most positive progress of all the G7 nations," the report said.
"Japan is isolated as the worst performer," Chris Lillecott of E3G told a news conference during negotiations between almost 200 nations in Bonn, Germany, on a U.N. climate agreement due at a summit in Paris in December.
It rated the G7 nations according to assessments about whether new coal-fired plants were likely to be built, how many existing coal plants were being retired, and how far each nation was involved in promoting coal-fired plants abroad.
U.S. installed coal capacity was more than double that of all other G7 members combined, at 288 Gigawatts.
But coal's share of U.S. electricity generation had fallen to below 40 percent since 2009, it said, helped by a rise in the use of shale gas. Many planned coal-fired plants had been canceled.
Jake Schmidt, of the U.S.-based Natural Resources Defense Council, said in a comment on the report that it was unusual for the United States to lead an international environmental ranking, but that big policy shifts were under way.
"Just a few years ago we were looking at a vast number of new coal-fired plants," he said.
The study said several of the G7 nations had implemented policies that would bar new coal-fired plants unless they capture and store their emissions of carbon dioxide, the main greenhouse gas blamed for stoking global warming.
"Only Japan persists in wanting to build new coal plants, leaving itself isolated among its G7 peers," the study said. Japan has shifted towards coal following the Fukushima nuclear disaster in 2011.
(Editing by Catherine Evans)