Wind power is the generation of a useable form of energy from the energy of the wind. Most commonly, wind power is used to generate electricity to be supplied to a nearby building or the grid. The energy is captured using wind turbines mounted on tall towers. Wind turbines can also be used to obtain hydrogen from water, using Magnetolysis or Electrolysis. The hydrogen can then be combusted in vehicle engines or used to generate electricity in fuel cells.
How Much Power can the Wind Produce?
Wind power is very strong and one of the least expensive forms of clean, renewable energy. A single, large wind turbine could provide enough electricity to power well over 1300 homes. Some European countries such as Denmark and Germany produce over 20% of their annual electricity needs through wind power. The UK has the largest wind generating potential in Europe (about 40% of Europe's wind), but only generates 1% of its energy needs this way. It is estimated that the UK could provide for its energy needs 10 times over using offshore wind farms.
Wind turbine technology is developing very fast, with larger, more powerful wind turbine being developed every year. They can come in a variety of sizes, from small units that can be fixed to the roof of your house, to medium sized stand-alone turbines for businesses and school, to 100 metre-high floating turbines that are anchored to the sea floor like an oil rig.
How Expensive is Wind Power?
Wind power is one of the cheapest forms of renewable energy, costing an average of 2.4 pence per unit to produce, compared to the industry average of 1.3 pence. Small-scale generation in homes is usually much cheaper than electricity generated by Solar Photovoltaic systems. Government grants are available for small-scale wind generation, bringing the cost down further. You can even make your own wind turbine using some plastic for the turbine's blades and a car's alternator as the generator.
The cost of wind power ultimately comes down to the average wind speed at the site. The higher the average wind speed, the more electricity will be generated, paying back the cost of the turbine quicker. Average wind speed increases with height, which is why wind turbines are often placed on hilltops and on top of tall towers. Turbulence is also an issue, so turbines placed clear of building, cliffs and trees will generate more electricity as the flow of air will be more constant. A flat-topped hill or location out at sea is ideal.
In the big picture, the cost of electricity from a newly erected, large-scale wind farm is competitive with that of a newly built coal power station, and about half the price of electricity generated from a newly built Nuclear Reactor.
How do Wind Turbines Work?
Wind turbines convert the motion of the air into a rotating motion. The blades of the wind turbine are pushed round by the wind, turning the axle in the centre. This rotational motion is used to drive a generator. It is like the opposite of a fan. With a fan, electrical energy is used to make wind; with a wind turbine, the wind is used to make electricity.
Wind Power for Home Generation
About a quarter of world energy demand could be met by individuals and businesses generating their own electricity from the wind. Small-scale wind turbines are available and government grants are also available for up to 50% of the costs. Many companies are now selling small wind turbines to homes, businesses and community projects for renewable energy generation. They require little maintenance and remain operational for over 20 years, protecting the owners from increasing energy costs and saving them money.
The energy available from the wind throughout the year is consistent with demand, with higher average wind speeds during the winter when the need for electricity is greatest. This is a particular advantage for small-scale users, who will want to use as much of their own energy as possible, with the rest being sold back to the grid.