Wind Energy
Sep
01
Wind energy converts kinetic energy that is present in the wind into more useful forms of energy such as mechanical energy or electricity. Wind energy is a pollution-free, infinitely sustainable form of energy. It doesn’t use fuel; it doesn’t produce greenhouse gasses, and it doesn’t produce toxic or radioactive waste.
Windmills that were used to grind grain are an example of early uses of wind energy. Modern uses of wind energy include generation of electricity and pumping water. Current wind energy machines are called “wind turbine generators”, “wind pumps”, or more generally, “wind turbines”.
The history of wind energy
Humans have used wind energy for thousands of years. Ancient Persians used wind energy to pump water before the birth of Christ. The world was explored by wind-driven ships long before engines were invented. As recently as the 1920s, over a million wind turbines pumped water and provided electricity to farms in North America.
The current interest in wind energy was started by the need to develop clean, sustainable energy systems that can be relied on for the long-term future. Modern aerodynamics and engineering have improved wind turbines. They now provide reliable, cost-effective, pollution-free energy for individual, community, and national applications.
The nature of wind energy
Wind energy is the kinetic energy that is present in moving air. The amount of potential energy depends mainly on wind speed, but is also affected slightly by the density of the air, which is determined by the air temperature, barometric pressure, and altitude.
For any wind turbine, the power and energy output increases dramatically as the wind speed increases. Therefore, the most cost-effective wind turbines are located in the windiest areas. Wind speed is affected by the local terrain and increases with height above the ground, so wind turbines are usually mounted on tall towers.
The costs of wind energy
The cost of wind energy is determined by:
- the initial cost of the wind turbine installation
- the interest rate on the money invested
- the amount of energy produced
Any wind turbine that is installed in a very windy area generates less expensive electricity than the same unit installed in a less windy area. So it’s important to assess the wind at the potential site.
Modern wind turbine generators cost between $1500 and $2000 per kilowatt for wind farms that use multiple-unit arrays of large machines. Smaller individual units cost up to $3000 per kilowatt. In good wind areas, the costs of generating electricity range between five and ten cents per kilowatt hour. That cost is somewhat higher than the costs associated with an electrical facility, but wind energy costs are decreasing every year, whereas most conventional generation costs continue to increase.
September 1st, 2008 at 11:01 am
Great introduction to wind energy. It’s the most affordable and competitive renewable energy source we’ve got so I expect we’ll only be seeing more wind turbines, not fewer.
If any of your readers are interested in supporting renewable energy but can’t or don’t want to build wind turbines themselves, renewable energy credits are a great option. You get all the benefits of a wind turbine sized to your exact requirements without the wind turbine in your own backyard. The simplest introduction to renewable energy credits are “Energy Seals” found as http://www.poweredgreen.com/. Check it out and go to the Learn > How It Works page to learn about how renewable energy credits from wind turbines work (very cool!). Thanks for the great article.