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Another thing we're good at: Wind

Wind is becoming a big business in farm country -- and it has nothing to do with the current political season.

Utility companies and farmers are erecting wind turbines by the hundreds in the upper Midwest and Great Plains, an area that's been called the Saudi Arabia of wind power because of its flat, open terrain and steady stiff winds. Take all the states from North Dakota down to the Texas panhandle, and the states that touch them, and you've defined the geography of this wind superpower.

At a meeting last week in Story county in central Iowa, farmers came to learn about wind energy and the giant wind farms that are being built by utility companies seeking renewable "green" energy sources. Extension service organizers had thought 50 people might attend, but were surprised with triple that number. Farmers there have a special reason to be interested, with a new wind farm under construction by Florida Power and Light in their county.

Here are a few of the facts that Bill Haman from the Iowa Energy Center told the group.

  • Wind itself is a byproduct of solar energy as the uneven heating and cooling of the earth's atmosphere creates pressure gradients. About two percent of solar energy that strikes the earth is converted to wind.

You get more power from cold wind at lower elevations. Both of those things cause the air to be more dense, giving the power boost.

Winds tend to be slower in the summer, when the air is warmer and packs less punch. Unfortunately, these summer "dog days" of wind power come at a time when electricity use peaks for air conditioner use. Since the power companies can't count on power from the wind when they need it the most, wind-generated electricity has a lower value to them compared to their coal- or gas-fired plants.

Most turbines you see spinning in farm fields have three long blades. While it might seem that more blades would harvest more wind power, that's not true. As the blades move through the air, they leave a wind cavity that has to be refilled for the next blade. Three blades take best advantage of this cavity refill.

You need a minimum of seven-mile-per-hour winds to operate most turbines. In Iowa, the year-around average wind speed at 160 feet above the ground is about 15 mph. It averages three to four mph faster in the winter and spring compared to the summer. Winds in far northwest Iowa average about 17 mph, compared to about 14 mph in the southeast part of that state.

A little extra wind means a lot. As the wind goes from a steady seven mph to 10 mph, the power output generated by a wind turbine triples. Go from 15 mph to 17, and you get a 46% power bump.

North Dakota should be the wind capital of the U.S. as it gets the steadiest, strongest winds coming off the western mountain ranges. A few years ago, it was calculated that if North Dakota could harvest all the wind power moving over it, and transmit it to where it's needed, it could provide 36% of all the electric power needs of the entire country. Unfortunately, the infrastructure and transmission lines to move that much power don't exist. And the cost to build it is prohibitive -- up to $1 million per mile. That's why most new wind farms are being built in states farther south and east, where the power grid is in place.

Towers in a wind farm need to be spaced apart at least three times the height of the towers. If they are 150 feet high, the distance separating each tower needs to be at least 450 feet. In many of the commercial wind farm settings, there's about one tower per 80 acres of land, or eight per square mile.

If you lease your land to a utility company for them to build a wind turbine, they will probably pay you an annual fee of one to two percent of the value of the electricity produced. In many cases, that's $2,000 to $5,000 per year, depending on size and output, as your payment. Usually, you give up less than an acre of land and you can farm up close to the tower base. You also have to provide an access lane to the turbine. Leases differ, so read the fine print.

The alternative to leasing out to a wind farm is to build and own the wind turbine yourself. You'll need to work with your local utility company, and many of them are willing to do that and buy excess power from you if you generate it (it makes them "greener"). A small residential turbine producing 10 kilowatts of power annually that could power your home and small farmstead could cost in the range of $25,000 to $40,000. And at the upper end, a large commercial generator capable of producing two megawatts (2,000 kilowatts) could cost $2 million to $3 million. There's such a high demand for those large units now that there is a 24- to 30-month wait for a new one.

Bill Haman encourages farmers to consider owning the wind turbines themselves, saying the returns may be better than taking the lease payment. There is one relatively new form of wind energy development called a Community Wind Farm. Two of these have been operating in Iowa since last spring, one with a group seven investors near Jefferson, Iowa, and the other with 10 farmer-investors near Ruthven, Iowa. The farmers have what is called a "flip" arrangement in which the power company puts up most of the initial installation money, and gets most of the returns for a 10-year period. At that point the equity "flips" to the farmers, and their returns escalate. This lets the farmers take an ownership position with much lower initial investment, and much bigger returns over the lifetime of the turbines.

Wind is becoming a big business in farm country -- and it has nothing to do with the current political season.

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