Turbine damage is still an everyday reality in the lifetime of a wind park. Owners are frustrated by repeated gearbox failures or blade repairs. In order to minimise failure rates and downtime it is becoming increasingly common to use independent assessors to check the status of the whole turbine or of certain critical parts like the gearbox or main bearings.

Energy Storage as a Matter of Urgency
 
As the penetration of wind power increases in the UK, the issue of the unpredictability of wind power could create problems for electricity traders and network balancing mechanisms. Market penetration is currently less than 2%, but traders are already discounting wind-generated power. If no mitigation is implemented, this situation could worsen as market penetration increases towards the goal of 15% renewables by 2015. The solution may be to use electrolysis of water to create hydrogen fuel, with the electrolysis operation being determined by the needs of the electricity networks.

The wind energy industry was initially encouraged to provide employment in the relatively poor North Sea regions of Germany. In the last 10 years, however, it has emerged  as a major business providing most competitive prices of electricity even when operated under marginal European wind conditions. The trade winds that blow along the Atlantic coast from Morocco to Senegal represent the largest and most productive wind potentials available on Earth. Because of the erratic nature of winds, however, wind energy cannot be integrated locally on any significant scale unless far-ranging, more advanced energy technologies are considered. The Sahara Wind Energy Development Project is looking at ways in which these large trade wind resources could be used to benefit both North Africa and Europe.

By Khalid Benhamou, Sahara Wind Inc., Morocco

Green Energy Technologies (GET), a company based in Akron, Ohio, USA, is introducing a unique wind system (with 1MW, 500kW, 100kw and custom rooftop models) called the SmartEnergy Spire, which creates a ‘wind tunnel’ effect forcing the wind around the Spire. Using the Bernoulli principle, the Spire design creates an efficiency of 1.676 two times the throughput over a traditional wind turbine using ambient wind.

Atmospheric stability has a significant influence on the wind profile, or the degree of increase of wind velocity with height. For tall wind turbines atmospheric stability is not a ‘small perturbation’ but a major factor determining the energy yield as well as the noise impact in the environment. Noise complaints and recent research show that noise from modern, tall, variable speed wind turbines is not a relatively featureless sound increasing steadily with near-ground wind speed, but – in a stable atmosphere – a thumping sound relatively independent of near-ground wind speed.