Wind energy is connected to solar energy. Sunrays heat air above ground, but it heats just the areas where is no cloudiness. These unbalances cause massive moves of air, known as wind. Wind energy has been used for various purposes during history, but today it is used solely for electric energy production.
Wind is a renewable source of energy with low external costs and massive potential for further growth. Wind energy industry undergoes rapid development and it employs 45000 people in Germany only. Technology progress helps to build still bigger wind generators. In 1992 the biggest power generator was around 200 kW with plates of 35 meters diameter. In 2000 the biggest generators plates diameter was around 80 meters and 900 kW power. Nowadays the 3,5 MW generators with 110 meters blades diameter are being tested. The generators are optimized to fulfill European noise norms. Adjustable plates are used to control rotation speed. Today’s wind power stations are equipped with asynchronous engines without gearbox.
The newest trends head to part reduction, and there are also significant efforts to reduce weight and increase flexibility of blades. More exact wind forecast is used to plan the output and therefore to reduce uncertainty of energy production. Very dynamic is also the trend of installation on the sea on continental shelves.
