Renewable energy development in China: Resource assessment, technology status, and greenhouse gas mitigation potential

China has become the third largest energy user in the world, and its coal-dominated energy structure implies high CO2 emissions. The amount of CO2 emissions from China may surpass that of the United States within 20-30 years, making China the world's largest source of greenhouse gases by 2020. Currently, renewable energy resources (except for hydropower) account for only a fraction of China's total energy consumption. However, China has abundant solar energy resources. More than two thirds of China receives an annual total insolation that exceeds 5.9 GJ/m2 (1,639 kWh/m2) with more than 2,200 hours of sunshine a year. Wind energy potential in China is about 3,200 GW, of which 253 GW is deemed technically exploitable. China has a wide range of biomass resources that can be used for energy supply and high temperature geothermal resources suitable for power generation located mainly in Tibet and Yunnan provinces. Renewable energy technologies have been actively deployed in China. Although PV power stations have not being connected to the national grid, total installed capacity was 3 MW in 1994. Solar water heaters are by far the largest solar thermal application in China with a total installed capacity of 3.3 million m2 in 1994. By the end of 1995, total installed capacity of grid-connected wind power plants had reached 36 MW. Also, over 140,000 small wind generators ranging in size from 50 W to 5 kW have been deployed with a total installed capacity of 17 MW. China is a world leader in the development and application of anaerobic technologies for the production of fuel gas and waste treatment and has by far the largest biomass gasification R&D capacity in the. Although renewable energy is projected to play a small role in future electricity generation, it is expected to be much more significant in the total energy sector. Under one scenario, renewable energy other than hydro provides up to 4% of the total energy supply and 88 million tons of carbon emission reduction by 2020. The estimated growth in greenhouse gas emissions, as well as serious local and regional environmental pollution problems caused by combustion of fossil fuels, provide strong arguments for the development of renewable energy resources.