What is a Wind Turbine?

Dotted across landscapes throughout the world, one can now see small, stick-thin structures with three spokes poking out from the central column. These structures are alarming, and almost sinister, the first time you see them. The world now recognises them as wind turbines, and their presence in the modern world is becoming more apparent.

Wind turbines are man’s primary way of generating electricity using the power of the wind. The versions of wind turbines we see now are merely an extension of an old idea; using the wind for power is no new concept. What is new is using the wind to generate electricity.

In the past, farmers would use windmills – the forerunner to the wind turbine, which in design they closely resemble – to power machinery to grind corn. These windmills can still be seen around the world, with Holland a well known location for windmills. The white structures we see across fields today are simply the 21st century version.

Wind turbines usually have three spokes, which when caught by the wind cause the mechanism to revolve. The spokes spin around driven by the force of the wind, and this in turn is used to power a machine – just like the windmills of old. However, the machines these turbines now power do not grind crops, but rather generate electricity through a traditional generator.

Wind turbines are one of the most – if not the most – effective ways of generating electricity. The energy produces is clean and, more importantly, renewable. So while these turbines may still cause mild shock when viewed in a place one did not expect them, they are nevertheless the future.

Local Onshore Wind Farms

A wind farm is an area which is host to several wind turbines, sometimes up to 100 individual turbines at a time. Rather than working as individual turbines, all of the energy collected by these wind farms is grouped into one larger generator of electricity; making such developments the power plant of the modern era.

The most common type of wind farm is the onshore wind farm. This essentially means where each wind turbine is anchored into land, usually on a grassy field or high on a hillside. Other forms of wind farms are possible; offshore wind farms are built in the sea, and airborne and near water wind farms are also increasingly common.

The reason for the onshore wind farm’s popularity is that they are easy to construct when compared with other options. Materials can be brought to the site, and while the transportation is expensive. When the component parts have arrived at the wind farm location, from there the erection of each turbine is relatively simple by modern engineering standards. Cranes are most typically used to winch the blades into place.

Onshore wind farms are most typically built in rural areas, though some cities are now building them close to urban areas. For example, a new wind farm in Glasgow, Scotland is only 20 miles from the centre of the city. While there are some aesthetic issues – particularly with local residents – this close proximity to where electricity is needed most means onshore wind farms can be extremely productive.

‘Shadow Flicker’ and Wind Turbines

If you do not live near a wind turbine, it is unlikely you will have ever heard the term ‘shadow flicker’ in everyday usage. The problem however is being discussed fervently by those who reside near onshore wind farms, and the matter is having to be settled by the courts in some cases.

Like all large structures, wind turbines cast a shadow. If one lives near enough to an active wind farm, this shadow may fall on your home at various points of the day. To many homeowners, this in itself is annoying, particularly if they live in rural areas and did not expect to have to deal with shadows falling on their property.

However, this is not the sole concern of those living near an active wind turbine. Unlike almost every other type of structure, wind turbines have three rotating blades. In the case of shadows cast on to a house, these blades themselves cast a shadow. However, the blades are in motion, so the shadow is a constantly moving menace that is extremely disturbing to witness. The constant passing of this shadow can occur for hours per day, and if residents are at home during that time, there is no escape.

Many energy companies refuse to exist shadow flicker is a problem, which has lead to many residents forming action groups. The solution is actually very simple, as shadow flicker will not occur if a turbine is placed 3,000 feet away from the nearest home. However, some energy companies have placed certain turbines as close to residences as 1,100 feet. Many anticipate changes in the law will prevent this from happening again, based on the evidence presented by annoyed existing residents who have to live with shadow flicker.