Power from the wind American wind resources Not all areas of the United States are equally suited to supplying energy from wind. The map below (Fig. E21.3.1 a) shows the regions that have significant resources. The availability ranges from very low (white) to deep blue (the greatest areas of wind availability). It is clear that the upper east and west coasts of the country are full of wind resources. There are seven categories of wind resources ranging from 1 (none) to 7 (superb, 800 to 1600 W/m2 at 50 m height). At this time, only resources in categories 5 (excellent, dark purple, 400 to 600 W/m2 at 50 m height), 6 (outstanding, red, 600 to 800 W/m2 at 50 m height) and 7 (superb, blue) are being exploited commercially. Fig. E21.3.1 The wind resources of the United States. Darker areas have more wind. (U.S. Department of Energy Refs. 30, 54) Additionally, the upper Midwest (the Dakotas, Minnesota, Iowa, Nebraska) have the greatest potential to sustain wind energy. It is for this reason that the Dakotas are sometimes called the Saudi Arabia of wind energy in America. The Texas panhandle and Oklahoma also have significant resources for wind energy. Archer and Jacobson have reevaluated possible wind power at 80 m at 8,000 sites globally and in the United States. They determined North America to have the greatest potential to supply wind energy, but identified many sites around the world.(a) Many farmers and landowners in these areas are leasing their land to power companies that site windmills there. Farmers may earn around $2,000/yr for each wind machine on their land.(55) The turbines use only about 500 square meters of land (about 1/8 acre), and farmers can farm the rest unhindered.(55) Crops net the farmers less than their rent, so it’s very attractive. Others are taking advantage of the wind as well. Sr. Paula Larson, prioress of the Sacred Heart Monastery in Richardson, ND, and Sr. Bernadette Bodine have written of the good experiences with the two used 100 kW wind turbines the sisters installed.(56) In 1999, the Monastery produced 242,870 kWh, of which 162,530 kWh was used and 80,340 kWh were transferred to the local co-op utility. They saved $14,920 in electricity costs and made $916 from sales to their co-op. These nuns spent $125,000 and had saved the Monastery well over $25,000 in electricity costs for the two years 1998 and 1999, about a 10-year payback.(56) The turbines should easily last another 20 years with proper maintenance, allowing the Monastery to save to buy newer, more efficient turbines when the present ones are retired. In 1999, the Monastery paid the co-op a bit over 9 cents per kWh, and obtained just a bit over 1 cent per kWh for the energy given the utility, saving a large sum. The nuns of Sacred Heart Monastery would be even happier, though, if North Dakota had required their co-op to pay them the same rate they had to pay. This is called “net metering.” With net metering, the person or organization would pay the going price for electricity for the net amount of energy used. If net metering had been a North Dakota law, the Monastery would have saved $22,300—over $7,000 more than they did—in 1999 alone! If net metering were law, the Monastery would have needed only a bit over 5 years to have paid off their investment. One of the most important suggestions in the report Repowering the Midwest is that net metering be instituted in all midwestern states not currently having it as law.(57) This is seen as very important in encouraging alternative energy producers (and of course makes sense for all states, not just the midwestern states, which are the focus of Ref. 57).(58) Many states, including Ohio and California, do have net metering laws. Fig. E21.3.2 A Darrieus windmill on the test site of Southern California Edison. a. b. Fig. E21.3.3 Energy from wind in the U.S. a. By region. b. By state. (U.S. Department of Energy, Ref. 15) Southern California Edison for some years tested various devices at its site in the San Gorgonio Pass (Figures E21.3.2) near Palm Springs. This is indicative of the approach to electricity generation in California. The Pacific Region of the country is the predominant region in renewable energy overall, as seen in Fig. E21.3.3 a. This is basically because the region contains California. Over the years, the state of California has led the rest of the United States in embracing renewables, as Fig. E21.3.3 b shows, producing roughly two- fifths of all America’s renewable energy. In the 1970s, wind turbines were the focus of government-supported research in the wake of the energy crisis.(35,42) The producers of renewable went into building facilities in a big way in the 1980s, constructing large wind farms because of newly-available government subsidies and tax breaks, both from the Federal Government and the state of California. Wind was much more expensive at that time than it is now, and the technology not so robust.(35) Fig. E21.3.4 Windmills in the San Gregornio Pass near Palm Springs, California. (U.S. Department of Energy, National Renewable Energy Laboratory) a. b. Fig. E21.3.5 Wind resources in California are located quite near the two largest cities. (California Energy Commission) As a result, wind producers struggled for some years, and as described below, it was only in the 1990s that the market recovered in the U.S. Southern California Edison continues to buy a lot of energy from wind farm producers in the San Gregornio Pass area (Fig. E21.3.4 and Fig. E21.3.5 b). Another private company put more than 700 wind machines in the Altamont Pass near San Francisco in the 1980s to sell to Pacific Gas and Electric (Fig. E21.3.5 a). The Reagan administration decided that wind energy research in the 1970s had reached commercialization and abruptly stopped further research. Instead, they put tax incentives in place to cause investors to build wind energy installations. About 900 MW was built through 1985, when the federal investment tax credits and California credits expired.(41,42) What was the result? Oil prices dropped from the mid-1980s through the mid-1990s as a result of the effectiveness of conservation measures in the United States and the rest of the developed world and the perceived threat to oil of these renewable resources. Natural gas prices tracked oil prices and remained low until the late 1990s. One result is that the amount of money saved by these renewables was much lower than it would have been if prices hadn’t dropped, as was projected when they were constructed. In addition, the Reagan administration assumptions about the maturity of wind turbine design was unwarranted. The problem is that the turbines were not as robust or well- constructed as had been thought by the politicians who intervened to stop the research for ideological reasons. Some California windfarms experienced low capacity factors of 5 to 10% because of mechanical failures and poor turbine design.(41) In addition, people who would have been expected to be supportive objected to the ugly tower framework, the number of birds killed by flying into the blades, and the loudness of the humming noise coming from improperly mounted or poorly designed blades.(41,42,59) Typical wind farm machines of the 1980s were in the 50 to 75 kW range. Recently, things have changed. Nowadays, wind turbines are generating much more power, as discussed in Extension 21.3, How a windmill works. Wind energy has become more widespread because of the globalization of the wind energy companies.(35,42) In the early 1980s, California possessed over 90% of all installed wind turbines in the world! While California still looms large with some 14,000 wind turbines producing about 1.8 GW (about 1% of California’s total electricity, and about 10% of the world’s total wind capacity), other states, especially in the midwest and southwest are catching up. Iowa now has the nation’s largest windfarm (Buena Vista County, rated at 112.5 MW),(15) and Minnesota also is increasing its use of wind energy (Pipestone County, 103.5 MW).(15) Between 1998 and 2001, these two states have added 500 MW of wind capacity.(57) Texas has around 50 MW installed. The California Energy Commission in the late 1990s and early 2000s authorized subsidizing almost 1 GW in new wind installations in California. Ironically, American producers sell most of their production abroad, and American firms import wind machines from Europe.(60) This is part of the nationwide explosion of interest in wind. Even though wind is only a small part of the total renewable energy picture in the United States—and the world—at present, this interest, and the perception of environmental friendliness among most people, is pushing worldwide growth. Figure E21.3.6 (next page) shows the worldwide growth of wind energy. Fig. E21.3.6 Wind energy capacity. (U.S. Department of Energy, National Renewable Energy Laboratory, Ref. 30) Apparently, about 2 construction jobs per megawatt installed are created. Possibly as many as 5 permanent jobs for every 100 MW of installed capacity are also created, so the local economic impact is not limited to the lease fees farmers receive.(30) In Antarctica, where electricity grids are not common, Admiral Byrd used a windmill in the 1930s to power his Antarctic base, Little America.(42) Several modern 280 kW windmills are also being used to replace dirty diesel generators at the Australian Antarctic base.(61) The manufacturing picture When the first wind machines were being installed in the 1980s, many American companies entered the market, but the most successful sellers sold Danish wind machines.