A factory worker walks past a pile of coal in an industrial area located on the outskirts of the city of Baotou, in China's Inner Mongolia Autonomous Region October 31, 2010. China's $736-billion push to harness nuclear, wind, solar and biomass energy hinges on making the cleaner fuels competitive with cheap and CO2-intensive coal without derailing surging industrial growth. The world's second-largest economy faces formidable challenges to make the plan work, with the upgrade to its rickety electricity grid needed, and the opening up of the network to alternative energy and raise tariffs to make new energy sources competitive with coal-fired power. The aim is to cut carbon intensity as much as 45 percent from 2005 levels by 2020 and increase the share of renewables to 15 percent of primary energy consumption. Picture taken October 31, 2010. REUTERS/David Gray (CHINA - Tags: ENERGY ENVIRONMENT)