WINDTEST Grevenbroich GmbH was founded in 1996 as an institute for measuring and certifying wind energy converters and for offering a wide range of services, expert opinions and consulting in the wind energy business. Near Grevenbroich, situated in the German state of Northrhine-Westphalia, south west of the state capital Duesseldorf, the WINDTEST Grevenbroich GmbH operates a test site. It is designed for up to eight wind energy converters (WEC) with rated powers ranging from 600 kW to 2,5 MW. Additionally there is a special site for operating and testing small WEC.