Moolamattam hydro power station - Credit: Wikimedia Commons
The Moolamattom hydro power station is the power house of the Kerala State Electricity Board's Idukki Hydroelectric Project, the largest hydroelectric project in Kerala, India, with a capacity to generate 2398 million units of electricity annually. Located at Moolamattam in Arakulam Gram Panchayat of Thodupuzha Taluk of Idukki district, it is one of the largest underground hydroelectric power stations in India. The power house has an installed capacity of 780 MW. In the three dams of this hydroelectric project, the water needed to generate electricity at the Moolamattam power station is pumped through tunnels (penstock pipes) near the pond level. Read more on Wikipedia
Source: en.wikipedia.org