Wind is free, but harnessing it to perform work can be very expensive. That's the case with today's wind turbines that are built to generate electricity.

The giant "green" alternatives to fossil fuel power plants now produce about 10 percent of America's electricity, and government authorities would like to see more.

The giant machines are produced overseas and in the U.S., and are hauled in pieces to remote "wind farms" by tractor-trailer rigs. Some trailers are more or less standard lowboys and drop-decks. Others are built specifically for this service. These include multi-axle Schnabel trailers where a turbine's tower section becomes part of the vehicle, as well as extendible-beam cradles to carry the long but relatively lightweight blades. Removable gooseneck trailers are also used at construction sites.

Seven rigs are usually needed to deliver each commercial-size turbine, which includes three tower sections; a nacelle containing a turbine's generator, gear box and electrical apparatus; and three long blades. These vehicles constitute a specialty for all involved - manufacturers, dealers and haulers.

Niche Market

"Wind energy is a niche, although it's a very expensive one," explains Barry Hale Jr. of Hale Trailers in Voorhees, N.J., which sells such equipment. For example, "A blade trailer costs about $120,000-plus, but that used to be $150,000" before trailer builders flooded the market.

"This was the hot ticket item, but wind energy took off at the exact wrong time," just before the economy plunged, he says. Many builders jumped into the business four to five years ago. It did well for a while, but the recession all but dried up funding, and expiration of federal tax credits stalled many investments.

Now there's "very, very limited activity," and Hale Trailers sells only five to 10 wind turbine-related trailers a year. But activity has picked up a bit since July, when federal stimulus money began flowing toward wind farms, says Greg Smith, vice president, sales and marketing for Talbert Manufacturing, one of the trailer suppliers.

Trail King was the original builder of wind turbine trailers, followed by International Specialized, Siebert and Talbert, Hale says. Many others got into it by copying trailer designs, and there are a lot of trailers now in fleets and on dealers' lots. This has depressed prices, a bad thing for builders and dealers but a good thing for fleets in the hauling business.

One of them is Landstar, which last spring hauled a General Electric wind turbine blade 2,428 miles from Aberdeen, S.D., to Dallas. To help GE promote wind power, SkyBitz tracked the 28-day journey and posted progress on a special website.

The trip took so long partly because the device was displayed to the public along the way. But all such loads are oversize, and some are overweight. Truck operators must study proposed routes for height and width clearances, obtain permits from multiple jurisdictions, and arrange for escorts, which sometimes must be police officers and their cars. Then the rigs can run only during specified hours.

On the Job

Some jurisdictions are harder than others to deal with, says Mark Humes, president of Blitz Transportation in Shelton, Wash., near Olympia. North and South Dakota, Pennsylvania and Texas are among the good states to deal with.

On a given day, Blitz's rigs might be all over the country hauling wind turbine pieces. Humes gets his loads from Integrated Wind Energy Services, Cape Girardeau, Mo., a consortium of independent haulers like Blitz.

Other large fleets include Lone Star and Anderson Truck Service. "They have the financial clout to get into these trailers," Hale says. Owner-operators have obtained trailers but then went bust with the economy. "There's a Catch-22: You can't get work unless you have a trailer and you can't get a trailer unless you have work."

An 80-ton-capacity double Schnabel trailer can cost $350,000 or more, says Greg Smith at Talbert, which just introduced such a model. It built two for Challenger Motor Freight, a large Canadian fleet.

"Blade trailers have become a commodity" since so many builders now offer them, Smith says. Also, an extendible-beam trailer can be modified to haul a blade.

In recent years makers of blade trailers have exhibited their vehicles at truck shows, where they gain an awed audience.

Each turbine blade is 120 to 130 feet long but weighs only about 20,000 pounds, says Barry Hale, who sells Talbert, Trail King and other trailer makes. So the whole shebang goes on only five axles, with the trailer rears spread to 10 feet, 1 inch, and wirelessly power-steered by someone in a chase car. There's considerable length to the extendible trailer and a lot of overhang from the blade.

A tower base is much shorter but more stout, with a diameter of 16 feet and weight of 65 tons. A two-part Schnabel holds each end of a cylindrical base or center section and carries it low to the pavement so overhead obstructions can be cleared. A lighter tower top section goes on a double-dolly rig with steerable rear axles. The generator nacelle, weighing 40 to 45 tons, goes on a 55-ton lowboy with a multi-axle jeep.

A rig carrying a nacelle or lower tower section can gross 120,000 to 180,000 pounds that's spread over 13 axles. Drivers and handlers are specialists, and everybody's careful with these loads, say those in the business.

Once in place and operating, wind turbines send many megawatts of electricity over power grids, replacing energy that would otherwise be produced from coal, natural gas or even imported petroleum. Thus wind generation cuts emissions of sulfur and other pollutants, and reduces release of carbon dioxide gas that's blamed for global warming. That's why governments encourage their erection.

Windy Issues

Impressive though they may be on the road and on a prairie landscape, not everyone likes wind turbines.

Some people think they're ugly and ruin the landscape or seascape. Some environmentalists complain that turbines take a lot of resources and energy to build, and that fast-spinning blades on older turbines have killed hundreds of thousands of birds. And studies have shown that nearby turbines double the night-time ambient background sound in rural areas.

By the way, wind turbines might look like windmills, and some folks call them that. But strictly speaking, windmills do mechanical work, like pump water or grind grain, says Wikipedia.com. Wind turbines convert wind energy into electricity for use elsewhere.

From the September 2010 issue of Heavy Duty Trucking magazine. Read more about trailer each week in Tom Berg's Trailer Talk blog