1)Hydropower impact on environment 2)The Disadvantage of Hydropower 3)The Hydropower station in Tibet China 4)The San Xia Dam Hydropower Station (China) The largest concrete hydraulic Project in the world Hydroelectricity is currently China’s largest renewable energy source and the second overall after coal. Although hydroelectricity represents the largest renewable and low greenhouse gas emissions energy source in the country, the social and environmental impact of dam construction in China has been large, with millions of people forced to relocate and large scale damage to the environment.