Electricity From Wind Turbines

How Does Wind Power Work?

Electricity from wind turbines is made using the natural power of the wind to drive a generator. The wind is a fantastic fuel as it's both clean and sustainable, it causes no pollution and won't ever run out. The technology to make electricity from wind turbines developing fast, turbines are getting cheaper and more powerful all the time, lowering the price of renewably-generated electricity. Europe is central to this high-tech industry as these are the countries which are most interested in how wind power works.

The need for clean energy

The more conventional methods of generating electricity work by burning fuel to provide steam which drives a generator, and therefore the turbine. This is done with fossil fuels like coal, oil or gas, or nuclear fuel. Fossil fuels won't last forever and also create pollution such as sulphur and nitrogen oxides that contribute to acid rain and carbon dioxide, which promote climate change across the globe.

Although European countries are mainly using conventional sources of power to generate their electricity, wind energy is growing rapidly. At the moment, renewable energy sources provide nearly 5.4% of the European Union's primary energy needs and can potentially provide much more.

So how does wind power work?

Generally, electricity from wind turbines is made by rotor blades which rotate around a horizontal hub, which is connected to a gearbox and generator found inside the 'nacelle'. The nacelle is mounted at the top of the tower and houses all the electrical components. This kind of turbine is known as a 'horizontal axis' machine.

There are lots of different turbine designs, with the most common being the up-wind, three bladed, stall controlled, constant speed machine. The next most popular design is similar, but pitch controlled. There are also gearless and variable speed machines and a smaller number of turbines with just 2 blades, or other concepts like a vertical axis.

Benefits of wind power

Wind energy has more advantages than simply generating electricity without causing pollution: -

• More countries have large potential for wind powerl than hydro-power or fossil fuel reserves.
• It's perfect for generating electricity on a local level. In europe most wind schemes are clusters of 10 - 40 turbines, which provides enough electricity for 4,000 to 16,000 households, plus Denmark and Germany also have a high number of single turbines. The electricity can be fed straight into the distribution network, reducing losses.
• Wind energy is great for island communities and the supply can be connected to solar or diesel systems as a back-up.
• There are few risks with wind power. The relatively small unit size of each wind turbine, or wind scheme, also minimises the risk of technical failure or industrial action compared with larger units.
• Wind energy encourages diversity. It's far better to have a balanced portfolio of energy technologies, than to rely on a small number of sources. Some countries rely more on importing energy than others, for example the UK has quite a varied mix of fuels, whereas other countries are more dependent on oil, coal and nuclear power. Expanding the use of wind energy will increase energy diversity and improve the security of electricity supply.