Small hydro-electric power plants

We are assured of the force of water every year during summer flood storms. Watermills, sawmills, fullingmills and pumps were usefull to our ancestors for hundreds of years. Water managers refer to technically marvelous water projects that originated as an energy source to drive the water pumps in mines in Banská Štiavnica. From between the 19th and 20th century small hydropower works started to rise on Slovak streams and rivers. They didn’t use water wheels but turbines (Aurel Stodola, Slovak technician and professor aided  significantly to their development). With their power they were able to serve to a village or a factory. After the war and communization the republic was in necessity of a lot of megaWatts and didn’t need tradesmen independent from state. Little hydro plants dissapeared and the rivers (mostly the Váh river) were tied into cascades which deprived the rivers of their natural functions. Large invasive interventions into the environment that are caused by middle-sized and large hydro plants achieved, that hydro plants were removed from the EU’s list of renewable energy sources. According to EU’s standards, a renewable energy source is only a small hydro plant with power less than 10 MW.

The power of a hydro plant is a function of fall-out and flow. That means a plant on a small stream that can utilise a fall-out of water greater than 100 meters can have larger power than a hydro plant on a big river on a lowland.