One of the key sources of renewable energy being developed today is wind power, utilizing giant turbines to generate electricity.  These work best in windy places like the U.S. Great Plains that stretch from west Texas in the south to the Dakotas in the north.  Wind power is nothing new in this region, where windmills have long played an important role in pumping water from underground aquifers and in milling grain.

Windmills were once seen on almost every farm and ranch in the American heartland.  The expansion of electrical service and the use of electric pumps brought an end to the windmill era, but visitors can still see dozens of these classic devices at the American Wind Power Center and Museum in Lubbock, Texas.  Around 90 windmills of various sizes and types are maintained inside the museum's massive building in Lubbock, on the Texas panhandle.

Executive director Coy Harris says machines that harvest wind power make a lot of sense in this part of west Texas.

"We see the wind blow a lot around here and it is a shame to just see it blowing dust," he said.  "We might as well do something with it."

The Wind Power Center obtains most of its operating power from a wind turbine atop a 50-meter-tall tower in its windmill park.  On good, windy days the turbine often produces more electricity than the center needs, so the excess is sold to the local power company.  On days when the turbine is not producing enough power, the center draws electricity from the local grid.

But since wind is intermittent, Coy Harris says cities and towns cannot rely on wind exclusively.

"They are going to still have to have coal-fired plants and everything else because people still want to have electricity even when the wind is not blowing," he said.

American Wind Power Center Development Director Glenn Patton says wind-generated electricity has great potential, but it is partly limited by out-of-date infrastructure.

"The problem is we have a grid system in certain areas that goes back to the 1940s, '50s and '60s and that grid system cannot handle the power of a wind turbine," he said.

But wind farms are being successfully operated in many parts of west Texas including a cotton processing plant near Lubbock.  There are also plans to develop wind farms on the Gulf of Mexico coast, another windy area not far from major urban zones like Houston and San Antonio.

"The places where you do see wind farms, either they are in a good area and have access to a major grid system or you will start seeing some wind turbines that actually will power or provide power to a particular manufacturing plant," he said.

But plans are under way here in Texas and elsewhere to connect wind farms in windy zones to grids in far away cities where demand is high.  

T. Boone Pickens, who made many billions of dollars in the oil and gas industry, is investing in a large wind farm to be built in the Texas panhandle.  Pickens estimates that more than 20 percent of the electrical power used in the United States in coming years could be produced by wind power.

His goal is to connect his turbines in west Texas to the Dallas-Fort Worth metropolitan area grid, but at least part of his plan has been sidetracked by the recent drop in oil and gas prices that make wind power less economical.

One of the big drawbacks of wind power is that its output cannot be regulated the way a plant fired by natural gas or coal can. Researchers are looking for effective ways to store excess energy for later use.

Glenn Patton says inventors more than a century ago developed efficient windmills using basic, but elegant mechanisms.  He says such innovation today may make wind power more viable as part of a basket of renewable sources of energy to power America's future.