The Multi-Effect-Solar (MES) power plant, patented by WITT SOLAR was planned and built together with Karlsruhe Institute of Technology (KIT) and M+M Turbinen-Technik GmbH. Within the project, the biggest solar thermal flat type collector in the world with an area of 120 m² has been constructed, as well an energy storage with a capacity of 12 hours. The R&D project was supported by the Federal Ministry of Education and Research – BMBF.
The MES is the first solar thermal power plant that operates at direct and diffuse light in difference to solar tower power plants and parabolic trough power plants, which are depending - to focus the solar rays - on direct solar sunshine, which is typical for clear skies. This capability of MES power plants extends the area of application for instance to Middle Europe and West Africa. MES has proven, to produce electricity and drinking water already at very low inlet steam temperatures of 50°C to 120° C. The uniqueness of a Multi-Effect-Solar (MES) power plant consists in its capability to producing both, electricity and drinking water in a single process step, especially for countries with problems in the supply with good and sufficient drinking water. Based on the central element of each engineered MES, the energy storage with a capacity of 12-24 hours, allows a dispatchable 24/7 operation for the production of electricity and drinking water.