OCEANIC SOLAR SYSTEMS

What is a wind turbine

Wind turbines are an alternative to Photovoltaic (PV) systems. Like PV systems they are environmental friendly and cost effective method to generate electricity. Once installed very little maintenance is needed and they generate electricity and recover their cost in the years following. They can even produce excess electricity which can be sold back to the grid.

Wind turbines operates on a simple principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity.

Wind turbines are mounted on a tower to capture the most energy at 100 feet (30 meters) or more above ground, they can take advantage of faster and less turbulent wind.

Wind turbines can be used to produce electricity for a single home or building, or they can be connected to an electricity grid for more widespread electricity distribution.

How do wind turbines work

The wind blows on the blades and makes them turn.
The blades turns a shaft inside the nacelle (the box at the top of the turbine)
The shaft goes into a gearbox which increases the rotation speed enough for the generator, which uses magnetic fields to convert the rotational energy into electrical energy. These are similar to those found in normal power stations.
The power output goes to a transformer, which converts the electricity coming out of the generator at around 700 Volts (V) to the right voltage for distribution system, typically 33,000 V.The national grid transmits the power around the country.

Instruments to measure the wind speed and direction are fitted on top of the nacelle. When the wind changes direction motors turn the nacelle, and the blades along with it, around to face the wind. The nacelle is also fitted with brakes, so that the turbine can be switched off in very high winds, like during storms. This prevents the turbine being damaged. All this information is recorded by computers and transmitted to a control centre, which means that people don't have to visit the turbine very often, just occasionally for a mechanical check. This is often done by local firms.
The real situation is more complicated, with many wind turbines, more voltages, different types of generators and safety systems, but this is a good guide to the basics.