UPDATE 2-China to lead 50 pct jump in world CO2 output-EIA

(Adds quotes from EIA, independent analyst)

NEW YORK, June 25 (Reuters) - The world's emissions of the main planet-warming gas carbon dioxide will rise over 50 percent to more than 42 billion tonnes per year from 2005 to 2030 as China leads a rise in burning coal, the U.S. government forecast on Wednesday.

China's coal demand will rise 3.2 percent annually from 2005 to 2030, the Energy Information Administration said in its International Energy Outlook 2008.

U.S. coal use will rise 1.1 percent during the same period, the statistical arm of the Department of Energy projected.

EIA economist Nasir Khilji said China's coal demand will likely rise steeply because it is the cheapest fuel to feed its surging manufacturing industry and demand for electricity as much of the population moves to urban areas.

In the United States a move to more nuclear power should help slow emissions growth, he said.

EIA raised its forecast of annual Chinese carbon emissions in 2030 by 6.8 percent from its outlook released last year, while cutting its forecast for 2030 carbon emissions in the United States by 13.8 percent.

"Coal's share of world energy use has increased sharply over the past few years, and without significant changes in existing laws and policies, particularly those related to greenhouse gas emissions, robust growth is likely to continue," the agency stated.

Not everyone agreed the forecast was accurate. Trevor Houser, a fellow at the Peterson Institute for International Economics, said the EIA forecast was based on the past five years of China's manufacturing rise, as it became an exporter of steel.