Wind turbine development and design - To future generations

One of the earliest 500 kW turbines world-wide was of NedWind manufacture and was installed in 1989 in the Netherlands. This forerunner of the current range of NedWind 500 kW machines also represents the earliest pre-design of the present NedWind MegaWatt turbine. After the first 500 kW turbine with steel rotor blades and a rotor diameter of 34 m, several design reviews followed, for example, the rotor diameter was increased to 35 m and tip brakes were introduced. Then polyester blades were specified with a further 5 m extension of the rotor diameter and a complete redesign of the drive train. The current concept permits rotor diameters of up to 43.77 m for inland locations. These continuing improvements in the design of the 500 kW turbine have improved reliability and decreased the cost price whilst simultaneously increasing the annual energy output to approximately 1.3 million kWh. NedWind made a large step forward by adapting the successful 500 kW technology of its NedWind 40 series to develop world's first commercial active stall regulated MegaWatt turbine with a rotor diameter of 52.6 m. Up-scaling the concept for 500 kW and MegaWatt machines has led to the introduction of the dual speed MegaWatt turbine with a rotor diameter of 55 m and a hub height of 70 m.