Ideal wind-farm locations are occasionally close to residential areas. That creates a problem because all turbines generate some noise. However, a lot of recent attention has been given to the noise wind turbines create and its impact on nearby communities. To address these concerns, many OEMs are searching for ways to reduce turbine noise, without compromising energy production. Nordex SE claims its N117/2400 wind turbine carries the industry’s lowest noise emission level for low-speed sites.

Nordex calls the N117 a Gamma Generation machine and says it is a viable option for residential areas because the acoustic power level is a maximum of 105 decibels. The tubular steel tower is certified as modular. The requirements of European Norm Standards, 50308 in particular, have been taken into account in the design of the tower interiors, such as access ladder, platforms, and safety equipment. The transformer can be installed inside or outside the tower. The turbine’s hub height reaches 91 meters, but remains below the 150-meter tip-height requirement. An 140-meter hybrid tower is also available.

The 2.4-MW turbine sports 117-m diameter rotor for a sweep of about 10,715 m2. The variable-speed rotor enhances the aerodynamic effects and reduces the wind load. In ideal conditions, the turbine can work for about 3,500 full-load hours per year allowing for steady electricity production in low winds.

Common in many of Nordex’s turbines is a double-fed asynchronous generator. The main advantage is that only 25 to 30% of the energy produced needs to be fed into the electricity grid via a frequency converter, while storing the remaining energy. Deployment of this generator and frequency converter system cuts the total cost of the wind turbine. WPE