Hydropower is clean, emissions free, reliable, renewable and cheap energy for generations. Hydropower uses the energy of flowing water, taking advantage of gravity and the water cycle. On Earth, water is constantly moved around in various states. Water evaporates from the oceans, forming into clouds, falling out as rain, gathering into streams and rivers, and flowing back to the sea. All this movement provides an enormous opportunity to harness useful energy.
All water used to move the turbine will be returned to its original river route, amount of water will remain same as before. Impact to the environment is nearly none as all water returned to its original river route, no chemicals involved and no fuels burned.
In 2011, 16 percent of the world’s electricity is provided by Hydropower, second only to fossil fuels. Worldwide capacity in 2011 was 950 GW, with 24% in China, 8% in the United States, 9% in Brazil and around 13% in Indonesia. Indonesia is blessed with topology and more than enough rainfalls that enables environmental friendly hydropower plants to be built .