Wind generators are generating a lot of interest right now, due to a high street DIY chain offering the first small wind generator commonly available for the home. We understand the argument that we need to dramatically reduce the emissions from the fuel and carbon we use, and wind as well as solar is one of the energy sources in plentiful supply, that we are learning to use.
Most of us has seen, or may live close by, one of the dozen wind farms established in barren, exposed parts of the UK – the Scottish Borders, and on Exmoor, are examples. Current plans to site up to 500 turbines on moorland on the Scottish Island of Lewis are provoking controversy.
One of the first areas to exploit the potential of wind farms was California, on America’s windy east coast. 3 huge wind farms, San Gorgino, Altamont Pass, and Tehachapi, in 1995 contributed 30% of the world’s wind-generated electricity. In 2004, 4,258 million kilowatt hours of electricity was generated by wind in California, 1.5% of the State of California’s total. It may not sound so much, but that is enough to power the City of San Francisco.
Once thought ugly, and the focus of initial community opposition, these farms with their huge, towering generators; new white megaliths on the land, are often now tourist attractions. We need them to contribute an increasing part of our energy needs, within a package of energy providers, as the public learns to wean itself off dwindling and polluting fossil fuels. But how do they work, and how much energy can they really contribute to our national grid system?
Harnessing Energy From Wind
Wind generators work by having their turbine blades, usually 3, rotate in the wind, turning a copper coil inside a magnetic field, which in turn creates an electrical current. Clearly the stronger the wind the faster the blades will turn, hence the importance of siting the generator in a high, exposed place, where wind is continuous, or as continuous as can be expected.
Electricity created inside this unit, the current, can then be fed through the system directly into the grid, via a grid tie inverter, which converts the currents voltage.
How much energy can this system really provide? And could it ever be enough to become the sole source of energy? At the moment, the total amount of energy harnessed and converted into usable power from wind turbines is low – estimates vary but it is probably below 3% of the total energy amount used within the UK. The solution to increase that amount is to build more wind farms, and plans are underway to do just that in the UK, as mentioned above on Lewis, and in the region of the Solway Firth, as well as in other areas, including off the North Sea off the North Norfolk and Northumbrian coastlines.
Suitable For Home Use?
Media reports about the small wind turbines that DIY stores are now selling are implying that this is just a craze and an effort to be seen to be green, following the lead of several politicians who are publicly declaring their intention to install them.
The most important aspect to consider is if your property is exposed enough to utilize enough wind. What really is worth considering first is a green energy audit for your home – if you are embarking on a self-build, then environmental considerations will be built in to your design and remit for the property. If you already have a property, and are looking for environmental improvements, possibly including a small, energy-generating turbine, then seek advice from an expert. Grants from local authorities are available which can offset the cost of these products, but only with certain types, and fitted by certain installers.