Hydropower was already in use in the pre-Christian era. In 100 B.C., the Roman architect Vitruvius described a grain mill that was driven by an undershot water wheel that, in principle, differs little from modern water mills. The generation of power in small hydroelectric power plants marks the beginning of public electrical supply systems. As technology advanced, the use of hydroelectric power expanded on large rivers since the beginning of the 20th century and enabled electricity to be generated more economically.
Against the background of the general discussion of the environment, people today are taking a new look at the numerous small hydroelectric power plants that were shut down in recent decades. Lohmann has been granted water use rights in Witten-Herbede. The grain mill, the rights for which reach back to the Middle Ages, is mentioned in 1770 as being owned by the former Baroness von Elverfeldt. Ownership was transferred to Lohmann in the middle of the 19th century when they purchased the mill and the surrounding properties. The Lohmann hydroelectric power plant has evolved from a grain mill driven by a water wheel on the mill channel in Herbede to a modern hydroelectric power plant consisting of four Francis turbines and a fully automatic control system. It includes a headwater channel that is used to supply water to the turbines and a tailwater channel to discharge the water into the Ruhr River. The weir located between the headwater and tailwater channels has a vertical drop of about three meters. The water flow rate of the turbines is 30.5 m³/s. The plant has a power output of about 600 kW. Approximately 4 million kWh are generated annually, which means about 1,200 households can be supplied with power.
The principle of hydropower is to convert mechanical motion or force into electrical energy using gears and generators. The electricity generated by the plant is consumed by our facilities and helps us make our production climate-neutral. Electricity from hydropower means resources like coal, oil, and gas are saved while protecting the climate and the environment at the same time. One kilowatt hour generated by hydropower saves one kilogram of carbon dioxide emissions (CO2 emissions) as well as the emissions of other pollutants. The impact and damage to the environment resulting from the use of fossil fuels and atomic energy are avoided when water is used to generate power.
The supply of resources – which is currently hot topic – is also limited due to increasing consumption. Protecting resources and the climate of the Earth are becoming more and more important in an advanced industrialized world (China, India, Turkey, new EU member countries) that continuously focuses on growth.
Hydroelectric power plants demonstrate that water used in this manner is a gift of nature, and therefore that hydroelectric power is a natural product of the highest quality through which we benefit from nature while protecting nature!