Ethanol is an additive used in gasoline. Through the use of renewable resources, the CO2 emission of fuels is significantly improved and the consumption of crude oil reduced. In modern ethanol plants, raw materials such as grain, sugar cane or sugar beet are processed into alcohol and ethanol. The resulting by-products and residues are also completely utilized. The different types of grain used for ethanol production are stored in silos more than 20 m high. Reliable silo level measurement is essential to ensure continuous production supply is maintained.