Spectra derived from ENVISAT Advanced Synthetic Aperture Radar (ASAR) and QuikSCAT near-surface ocean winds are investigated over the North Sea. The two sensors offer a wide range of spatial resolutions, from 600 m to 25 km, with different spatial coverage over the area of interest. This provides a unique opportunity to study the impact of the spatial resolution on the spectral properties of th...

The IEA WIND Task 25 also known as the " Design and Operation of Power Systems with Large Amounts of Wind Power " , Task 25 of IEA Implementing Agreement on Wind Energy, functions within a framework created by the International Energy Agency (IEA). Views, findings and publications of IEA WIND Task 25 do not necessarily represent the views or policies of the IEA Secretariat or of all its individ...

Offshore wind turbines face ever increasing challenges from the harsh environment of humidity, corrosion, vibration etc. at sea. The effect of the environment on the equipment employed at sea has caused many problems in terms of delay of projects, reduced reliability, down periods etc. Knowledge of the electrical, climatic and mechanical conditions to be conquered and their impact on the differ...

In recent years, the Indian Ocean (IO) has been discovered to have a much larger impact on climate variability than previously thought. This paper reviews processes in which the IO is, or appears to be, actively involved. We begin the mathematical model with a pattern for summer monsoon winds. Three dimensional temperature and velocity fields are calculated analytically for the ocean forced by ...

High-voltage direct current (HVDC) lines with line-commutated converter (LCC) are being increasingly employed to transmit bulk wind power over long distance. However, this may cause the sub-synchronous torsional interaction (SSTI) between the wind farms and the LCC-HVDC system. The SSTI characteristics of wind farms with fixed-speed induction generator (FSIG) wind turbines connected to LCC-HVDC...

Building upon a recent study that showed windbreaks to be effective in increasing the power output of a wind turbine, the potential of windbreaks in a large wind farm is explored using simplified formulations. A top-down boundary layer approach is combined with methods of estimating both the roughness effects of windbreaks and the induced inviscid speed-up for nearby turbines to investigate pow...

In the Netherlands the Dutch government has set a very ambitious target for offshore wind energy of 6000 megawatt in 2020. Environmental impact of wind energy plays an important role in the public acceptance that also influences the decision-making processes. Since the introduction of wind energy, there is a concern that turbines would cause harm to birds. A lot of studies about nuisance to bir...

There have been many wind integration studies in recent years, with evolving methodologies. Since power systems and data availability vary significantly, the results and methodologies used in these studies have varied accordingly. This paper presents findings from an international collaboration under IEA WIND Task 25 working towards Recommended Practices for Wind Integration studies. An overvie...