Green shorts - Wind power generation

 

 

Wind power
Wind generators are devices that produce electricity from the power of the wind. Inside the body of a generator, there is a coil of wire and a magnet. When a coil of wire is moved inside a magnetic field, it produces an electric current in the wire - the same principle as a dynamo, but here the wind provides the movement. Wind farms have many generators which produce a large amount of power.
Perhaps the ultimate solution to complaints is to put wind generators offshore, where winds are strong and there are no neighbours; however the main drawback is the cost of building in such a harsh environment. Nevertheless the UK has the best wind resource in Europe; with the possibility of producing 20% of our needs from this resource.

Offshore wind
Offshore wind is a larger-scale, more technologically challenging and expensive undertaking than onshore wind. However, it has huge potential due to the UK’s excellent offshore wind resource, which is stronger and more consistent than the wind resource onshore, leading to higher power outputs per turbine and more hours spent generating each year.
Offshore turbines operate in much the same way as onshore turbines, although in general they are larger and more powerful. The construction, delivery and assembly of such large machines require specialist equipment; facilities at ports and installation vessels. Careful scheduling is also needed as offshore turbines can only be installed in calm seas. Changeable weather and sea conditions also mean that offshore turbines need to be extremely robust. Offshore wind turbines also require underwater cabling to transport electricity back onshore and into the grid.

What are the benefits?
Wind generators are the main viable alternative to fossil fuels and nuclear power in the UK: as such wind power has the potential to replace currently existing generating technologies which cause a wide range of environmental problems.
Wind generators have a good energy ratio: generating many times the energy needed to make them. Wind is also suitable for small installations, unlike many other generation technologies which are only viable on a large scale. Safety and reliability are also good - a properly installed wind generator should operate without problems for 20 years or more.

Installation
It’s a good idea to combine wind with solar, to take advantage of all weather conditions. Wind generators are ideal on their own for boats and caravans, where less electricity is needed, and also for remote, off-the-grid homes, in conjunction with a diesel generator.
Check the wind speeds at your location, through the DTI web services, then look at graphs provided by manufacturers for their turbines to see what power (in Watts) you will get for your average windspeed. Divide by 1000 to get kW, and multiply by the number of hours in a year (8760) to find the kWh generated per year (1 kWh is the basic unit of electricity on your electricity bill).
Talk to your local planners (for a small turbine, this is no longer a problem), and choose a site away from trees and buildings (rural areas are much better sites).
Decide whether you will use a battery bank, or be grid connected; electricity companies often pay a lot less for energy received than supplied. There is a third way, called grid interface. Batteries are used but the grid kicks in via a transfer switch if the batteries get low.
You can also buy 12-volt domestic appliances, in which case you just need batteries and a regulator, or you can use normal 240v appliances, but you’ll need an inverter for this aswell.

 

Further information
Renewables explained
Renewables explained - Wind

Wind energy facts
The 'Wind Energy – The Facts' publication is widely considered to be the most important wind energy reference in the world. It presents a detailed overview of the wind energy sector, with the most up-to-date and in-depth information on the essential issues concerning wind power today.
Wind energy - the facts