KEARNEY - For centuries, entrepreneurs have used windmills to pump water, operate sawmills and flour mills, and generate power.

So constructing massive, modern windmills to generate a significant part of the nation's electricity seems like a logical advancement in harnessing wind for a 21st-century world.

"The wind is always blowing somewhere," Susan Williams Sloan of Austin, Texas, outreach manager for the Washington, D.C.,-based American Wind Energy Association, said Tuesday to open the first Nebraska Wind Energy Conference in Kearney.

That's especially true in Great Plains states with the greatest potential for wind energy development.

Nebraska ranked sixth in a study of states' wind generation traits, "but that potential is mostly untapped," said state Sen. Don Preister of Lincoln, who co-chairs the Nebraska Wind Working Group with state Sen. Cap Dierks of Ewing and Nebraska Farmers Union President John Hansen of Lincoln.

The working group and Nebraska Energy Office are hosts for the Wind Energy Conference, which concludes this afternoon. An estimated 500 people had registered in advance or at the door by Tuesday's opening session.

"This is a pro-wind group," Preister said. "... This is not a balanced conference."

State Sen. Joel Johnson of Kearney described wind as a commodity Nebraskans need to develop to the fullest extent possible.

Sloan agreed, "The United States has some of the best wind in the world and some of the best wind is blowing across Nebraska."

That means the state could cash in on economic development opportunities, including new jobs in wind turbine construction, operations, equipment manufacturing and related industries, and help meet a goal to have 20 percent of U.S. energy come from wind by 2030.

Sloan said the goal requires growing the current 20,000 megawatts of installed wind generation - enough to serve 5.3 million homes or power 1 million hybrid vehicles - to 300,000 megawatts by 2030.

Surrounding states have a big lead in current capacity. For example, Nebraska's 73 megawatts compares to nearly 1,400 megawatts in Iowa.

Costs, benefits and challenges of meeting the 20 percent goal were analyzed in a U.S. Department of Energy study.

It concluded that the cost of proceeding with wind energy were 2 percent more than meeting growing energy demands with conventional production. Sloan said that difference of $43 billion is about 50 cents per household per month.

Benefits identified include a potential 50 percent drop in natural gas use for electricity and 11 percent for all uses and an 18 percent decline in coal use for electricity, resulting in avoiding costs to construct new coal-fired power plants.

Water savings estimated at 17 percent from the electricity sector also are important, Sloan said, because limited water supplies result in difficult political choices.

Gains in local property taxes were estimated at $1.5 billion, with another $600 million added to local economies from lease payments to landowners. More than 500,000 additional jobs could be supported by new wind energy development.

More difficult to quantify are benefits from reducing carbon dioxide emissions. Sloan said that's of particular interest to large industries needing to reduce their carbon footprints, especially if climate change concerns result in more regulations.

All those benefits come with huge challenges, she said, starting with the need to build transmission systems to get electricity from lightly populated windy areas to high-demand "load centers." President-elect Barack Obama has talked about the need for new energy infrastructures, so Sloan hopes the issue will be addressed.

A related issue is integrating wind power into the current energy system.

Sloan said wind production isn't constant, but it can be more reliable if turbines cover large geographic areas and experts are hired who can better forecast the timing and type of wind available. Those measures help with more accurate power generation planning.

Other challenges include improving wind generation technology, addressing concerns about acquiring wind farm and transmission line sites, training wind industry workers, and solving issues in transporting huge turbine equipment.

"Getting to 20 percent is not going to be business as usual," Sloan said.

"Part of the beauty of Nebraska is we're the only 100 percent public power state in the nation," Hansen said. "We're not just ratepayers. We're stakeholders."