Trenčín hydroelectric power plant is the last HPP on the historically first diversion channel, but it is built with a time delay, therefore it is already designed to a flow rate of 2 x 90 = 180 m3.sec-1, equal to that of the HPP downstream cascade. A system featuring a heat pump to make use of the waste cooling water heat was installed at the Trenčín HPP during the construction. This system has provided to date for heating of the Trenčín HPP and of the adjacent premises. The water used at the Trenčín HPP flows together with the Váh riverbed water into the Trenčianske Biskupice weir, which is a retention reservoir for the Nové Mesto cascade.
Slovenské elektrárne operates 31 hydroelectric plants. Their combined output is 1,652.7 MW, representing approximately 38.4% of the Company’s total installed capacity. Majority of the installations is located on the Váh River cascade, or the longest river in Slovakia. On average, the hydroelectric sources generate 2,070 MW annually (consumption of pumped storage power stations excluded), or some 11% of the electricity produced by Slovenské elektrárne.
Because of their very variable power output and operational flexibility, hydroelectric plants are capable to satisfy the swiftly changing demands in the daily-load diagram, pairing nicely with the base load supply covered by nuclear power plants. Slovenské elektrárne has 736.6 MW installed in river hydropower plants and 916.4 MW in pumped storage power stations.