Farming the Wind

In the Midwest the wind blows across fields of corn, soybeans, wheat, and wind turbines—wind turbines It turns out that the wind that seems to blow almost continuously across the plains is now becoming the latest cash crop. One of these new-breed wind farmers is Daniel Juhl, who recently erected 17 wind turbines on six acres of land near Woodstock, Minnesota. These turbines can generate as much as 10 megawatts (MW) of electricity, which Juhl sells to the local electrical utility. 

The largest wind farm in the world, located on the Oregon-Washington border, generates 300 MW. A controversial wind farm in the ocean five miles off the coast of Cape Cod is planned to produce more than 400 MW of power. 

There is plenty of untapped wind power in the United States. Wind mappers rate regions on a scale of 1 to 6 (with 6 being the best) to indicate the quality of the wind resource. Wind farms are now being developed in areas rated from 4 to 6. The farmers who own the land welcome the increased income derived from the wind blowing 

Stateline Wind Generating Project in Walla Walla, Washington. 

The higgest hurdle that must be overcome before wind power can become a significant electricity producer in the United States is construction of the transmission infrastructure—the power lines needed to move the electricity from the rural areas to the cities where most of the power is used. For example, the hundreds of turbines planned in southwest Minnesota in a development called Buffalo Ridge could supply enough electricity to power 1 million homes if transmission problems can be solved. 

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Chemicat Connections describe current applications of chemistry. These special-interest boxes cover such topics as the invention of Post-It Notes, farming the wind, and the use of iron metal to clean up contaminated ground-water. Additional Chemicai Connections are available on the student website. 

Aerodynamic drag has also been used to capture energy from the wind. Drag mechanisms consist of flat or cup-shaped devices that turn the rotor. The wind simply pushes the device around the main shaft. Anemometers used to measure wind speed are often drag devices, as are traditional farm windmills. 

Since 1992, more commercial wind farms have been installed than ever before with 40,000 turbines in 40 countries. Wind energy capacity is growing at almost 30% annually. By 1998, it reached 10,000 megawatts (MW), which can supply a country the size of Denmark and the wind power industry had sales of 2 billion with 35,000 jobs worldwide. The prime movers were an increasing environmental awareness and commitments to reduce greenhouse gas emissions made under the Kyoto Protocol of 1997. 

Wind energy Wind turbines capture the energy from the wind to produce electricity. They have been developed for various purposes, from large groups of grid-connected wind turbines, wind farms, both onshore and offshore, to very small autonomous turbines used for battery charging or in combined wind-diesel projects for off-grid application. 

Mesa Power LLC, headed by legendary energy investor T. Boone Pickens, has been making headlines with its plans for a vast wind farm, the Pampa Wind Project, in the Texas panhandle that may eventually include 2,700 wind turbines generating 4,000 megawatts of electricity. Pickens is... 

Figure 1.20 illustrates a typical wind farm. The DOE estimates that in the next 15 years wind generator capacity in the United States will reach between... 

American Electric Power is installing a 6 mW wind farm with battery storage for 27 million, or at a unit cost of 4,500/kW, using NGK Insulator s sodium-sulfur batteries made in Japan. The rationale for the installation is that although the wind turbines operate mostly at night when the value of electricity is low, by storing the electricity generated until the next peak period, its value is much increased. 

The top right of Figure 1.22 shows the tidal turbine that can be used in many tidal areas. They are basically wind turbines that can be located anywhere there is strong tidal flow. They are arrayed underwater in rows, as in some wind farms. The turbines function best where coastal currents run between 3.6 and 4.9 knots (4 and 5.5 mph). In currents of that speed, a 15-meter (49.2-feet) diameter tidal turbine can generate as much energy as a 60-meter (197-feet) diameter wind turbine. Ideal locations for tidal turbine farms are close to shore in water depths of 20-30 meters (65.5-98.5 feet). 

For land-based wind farms, once the wind towers are installed, the land area around them can be used for other purposes, such as agricultural use. 

As with any source of energy, there are some drawbacks to wind power.The most significant is that the wind to drive the turbines may be intermittent and that it does not always blow when electricity is needed. Wind energy may only be available 40 percent of the year in some areas versus 90 percent for a fossil-fuel powered plant. New blade design can overcome this problem to a certain extent, as can storing the energy in batteries, but because of these potential drawbacks, the site of the wind farm is key to its success and vice versa. 

These delivered costs include a 10 percent transmission cost from the wind farms to the distributed hydrogen facility. This transmission cost is consistent with the wind farms being located in the geographical vicinity of the hydrogen facility, but not at the facility. 

Landscapes of our planet become more and more artificial today. Canopies of an artificial kind have replaced forests in some places. One of the examples gives a wind farm consisted of a cluster of wind turbines [168]. Each wind turbine takes out some momentum from the passing wind, thus causing a reduction in the wind speed at the... 

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