Theory:

Running water is a great source of energy. Turbines and dynamos are used to generate electricity from water moving with high velocity and great falls. This electricity is called Hydro-electricity. Hydro-electricity is the cheapest and most versatile source of energy among all the known renewable energy. China is the largest producer of hydro-electricity. Important hydro-electricity producing countries are: China, Canada, Brazil, the United States of America, Russia, India, Norway and Japan.
 
S.No.
Hydro-electricity power
Installed Capacity (MW)
State
River
1.Tehri Dam2400UttarakhandBhagirathi
2.Srisailam Dam1670Andhra PradeshKrishna
3.Nagarjuna Sagar Dam960Andhra PradeshKrishna
4.Sardar Sarovar Dam1450GujaratNarmada
5.Bhakra Nangal Dam1325PunjabSutlej
6.Koyna Dam1960MaharashtraKoyna
7.Mettur Dam120TamilnaduKaveri
8.Idukki Dam780KeralaPeriyar
Three Gorges Dam in China:
This dam is the largest hydroelectricity project in the world. Its construction started in 1994 and ended in 2012. The installed capacity of the dam is \(22,500MW\).
three gorges dam.jpg
Three gorges dam
S.No. 
Name of the power project
Country
River
Installed Capacity in MW
1.Three gorges DamChinaYangtze 22,500
2.Itaipu DamBrazil and ParaguayParana 14,000
3.Xiluodu DamChinaJinsha 13,860
4.Guri DamVenezuelaCaroni 10,235
5.Tucurui DamBrazilTocantins 8,370
Tehri Dam in Uttarakhand is the highest dam in India.
Hirakud Dam in Odisha is the longest dam in India.