WHAT IS WIND ENERGY ?

Man has used the wind for thousands of years.

The most obvious way to get free energy was as power for transport - sailing ships - man has sailed the seas to trade, invade or explore, and has changed the world forever.

And then there were windmills, used for hundreds of years to pump water or grind grain, which have since become beloved symbols of a bygone age.

The principle of the turbine is also very old and is nowadays seen at work in hydro-electric plants and aircraft jet engines. The principle is that the turbine blades are turned by steam or water or air, and this then operates an electric generator.

With wind turbines (or WEC, wind energy converters) the rotor blades are very long to compensate for the low density of the air - relative to water for example where the turbine fans can be much smaller. Wind turbines are built in areas where the wind is constant in speed and direction, rather than somewhere where the wind is very fast only sometimes.

The towers are built as high as possible to access the slightly faster and less disturbed airflow. The nacelle houses the generator and computer controlled engines for keeping the turbine facing into the wind. The rotor is made up of the blades and the hub, which connects to the generator via a drive shaft. The electricity produced is then processed by transformers at ground level to increase the voltage for safe onward transmission by power lines.

Wind turbines do not produce any radiation or harmful emissions. They produce no greenhouse gases and no environmentally damaging matter. The noise the generators make is almost inaudible at ground level, although the swish of the blades can be heard nearby. The flicker effect of the sun shining through the blades is normally calculated so that the turbines can be programmed to shut off at critical times. At the Judith Gap site there is no habitation and so the turbines can operate at maximum efficiency.

For more information you will find the American Wind Energy Association web site very interesting - www.awea.org - and if you still have questions the answers will be found at - www.windpower.org/tour/index.htm - a Danish produced English language web site.