An Overview Of Wind Power

In 1995 the world had about 5,000 megawatts of wind power, about the equal of five large coal or standard nuclear power plants. By 2006, the capacity jumped to 70,000 MW, and is today at around 100,000 MW. Germany is #1 with 23,000 MW, the U.S. #2 and approaching 20,000 MW with Spain #3 at more than 15,000 MW. North Dakota supposedly has potential for close to 140,000 MW, Texas 136,000 MW and Kansas about 120,000 MW.

On May 12, the U.S. Department of Energy issued a detailed analysis stating that wind power, currently at 1%, could provide up to 20 percent of the nation's electric power by 2030. Amazingly, this renewable option accounted for 35 percent of the new electricity generating capacity added nationally last year. Thus, wind power has most definitely captured the imagination of the investment public. Why? Because it is financially competitive.

A simple motivation is profit. Lester Brown reports that farmers with no investment on their part, can annually gain revenues of up to 5,000 per acre on land that would provide a corn crop worth 120 or beef at 15. This land can still be used to grow corn and ranch cattle.

Coal and nuclear powerplants produce electricity for around 3 cents/kWh, although there are some looming fuel cost, storage and carbon problems that could well double that price, especially for coal. Geothermal electricity is also in this range, and all three are baseload, that is, they are available most of the time. Wind and solar power plants are intermittent, and that is a major handicap, suggesting that some storage complement must be included into the cost equation. Wind power is at about 5 cents/kWh, but will probably continue to be assisted by a 1.8 cents/kWh production credit, making this renewable option quite competitive with these more conventional options. Utility solar thermal plants are around 10 cents/kWh and solar photovoltaics still more than 20 cents/kWh.

Wind electricity is cleaner than the more conventional forms relative to global warming (grams carbon dioxide per KWh):

o Coal fired power plant 667

o Natural gas fired power plant 400

o Coal fired power plant with carbon capture 200

o PV station 30

o Nuclear fired-power plant 25

o Wind power 11

Regarding wind power in general, it turns out that, theoretically, the smaller the number of blades, the more efficient the rotor. One bladed (counterweighted) windmills have been built, but they have been unstable. Thus, a WECS with two blades (one propeller across the hub) should be best. However, for stability and start-up purposes, three-bladed systems seem to be prevailing.

A good wind site is the key. If two same-sized wind energy conversion systems (WECS) are used at 10 miles per hour and 20 MPH locations, the output at the latter will be 8 times higher because power varies with the cube of the velocity: 20 divided by 10 equals 2, which has to be cubed to obtain 8. Unfortunately, there tends to be more turbulence at some higher velocity locations, so the rules of thumbs are: DON'T install one at home (the average wind speed will almost certainly be too low) on a whim and be very careful around mountains.

The future looks outstanding for wind power. In time, sites like Antarctica can be considered, for Australia's Mawson base averages, reportedly, 11 m/s (24.8 MPH), but speeds up to 69.5 m/s (155 MPH) have been measured. Can a system be developed to survive these conditions?

High altitude concepts have been advanced, using moored kites and other devices in the upper atmosphere. The jet stream 5 to 10 miles up has winds at 300 MPH. The potential! Oil today ended at 122/barrel.