About 80 percent of the increase will come from countries not part of the Organization for Economic Cooperation and Development, the International Energy Agency forecasts in its annual World Energy Outlook.

The share of fossil fuels in total global power generation is expected to fall to 55 percent in 2035 from 68 percent in 2008 as governments and utilities worldwide boost the use of renewables and nuclear energy to reduce global warming, the Paris-based organization said today.

Coal will remain the biggest source of electricity generation in 2035, with its share falling to 32 percent from 41 percent now, according to IEA’s New Policy Scenario. Natural- gas-fired generation will remain at 21 percent.

China, the world’s biggest energy user, will add generation capacity equivalent to the installed capacity of the U.S. in the next 15 years as consumption is expected to triple between 2008 and 2035, IEA said. The country will add about 600 gigawatts of coal-fired generation capacity in the next 25 years, IEA Chief Economist Faith Birol said today at a press conference in London.