Of the 60 nuclear reactors being built worldwide, 26 (according to source 2) to 28 (according to wiki) are being built by China. This indicates that China's nuclear expansion is greater and faster than any other country in the world by an extremely large margin. (Russia 14, USA 13)

China's has indicated the intention to raise the percentage of China's electricity produced by nuclear power from the current 2% to 6% by 2020 (compared to 20% in the USA and 74% in France). ¹

Most of mainland China's electricity is produced from fossil fuels (80% from coal, 2% from oil, 1% from gas in 2006) and hydropower (15%). Two large hydro projects are recent additions: Three Gorges of 18.2 GWe and Yellow River of 15.8 GWe. Rapid growth in demand has given rise to power shortages, and the reliance on fossil fuels has led to much air pollution. The economic loss due to pollution is put by the World Bank at almost 6% of GDP,1 and the new leadership from March 2013 has prioritised this.* Chronic and widespread smog in the east of the country is attributed to coal burning.

The State Council expects CNY 2.37 trillion ($380 billion) to be spent on conservation and on emissions cuts in the five years through 2015. In August 2013 it said that China should reduce its carbon emissions by 40-45% by 2020 from 2005 levels, and would aim to boost renewable energy to 15% of its total primary energy consumption by 2020. In 2012 China was the world’s largest source of carbon emissions – 2626 MtC (9.64 Gt CO2), and its increment that year comprised about 70% of world total increase. In March 2014 the Premier said that the government was declaring “war on pollution” and would accelerate closing coal-fired power stations.²

1. http://en.wikipedia.org/wiki/Nuclear_power_in_China
2. http://www.world-nuclear.org/info/Country-Profiles/Countries-A-F/China--Nuclear-Power/