For decades, people have dreamed of generating electricity on a large scale without creating pollution or radioactive waste. That clean-energy dream now appears closer to becoming a reality.
The reason is the explosive growth of wind power, which experts say is finally coming of age as a viable energy source.
During the 1990s, wind-energy capacity grew by an average of 26 percent annually, and last year by 35 percent, making it the fastest-growing electricity sector. Despite barriers, it's now a $2 billion world industry, capable of producing more than 10,000 megawatts of electricity, enough to meet the residential needs of Washington, D.C., for more than 16 years.
"It's really the first major new way of generating electricity since the emergence of nuclear power several decades ago," says Christopher Flavin, senior vice president of the Worldwatch Institute in Washington. "The industry ... has major potential to become an important part of electricity generation in the years ahead," he says.
"Until not long ago at our conferences we'd still see people with long hair and nice ideas. Now there are more ties and three-piece suits than anything else," says Christophe Bourillon, head of the London-based European Wind Energy Association. "We've moved from being the big boy in the small pond of renewable energy to a mature industry competing with far larger oil, gas, and nuclear sectors."
Most of the recent growth has been in Europe, where governments have encouraged wind-power developments through research investments and other incentives. Denmark generates 8 percent of its power from wind, and sales of high-tech Danish wind turbines generate $1 billion in annual sales.
Wind turbines produce 20 percent of the electricity used in Spain's industrial state of Navarra, and 11 percent used by Germany's Schleswig-Holstein, says Worldwatch.
Industry sources attribute wind's rapid growth to a combination of technological breakthroughs and government policies in support of renewable energy. Growth has also been self-reinforcing because component costs are driven down as the industry reaches increasingly efficient economies of scale.
Spurring the US drive
"There's no longer any doubt that this technology is going to make it in a big way," says Randall Swisher, executive director of the American Wind Energy Association in Washington. Wind power "has really broken out. It's only a question of how far and how fast it will grow."
The US industry received an important boost June 21, when Energy Secretary Bill Richardson announced an initiative to have wind supply 5 percent of the nation's electricity.
"By 2020, we want wind energy to be a major commercial-power generation technology, helping supply the nation's electricity needs and leading the charge in the transition to renewable energy," Richardson said.
The measure appears to have solid bipartisan support in Congress.
Analysts say the US has catching up to do. "The US early on was the big leader in designing and building [wind] machines, but now we're being overshadowed by developments in Europe," says Robert Thresher, director of the National Wind Technology Center, an Energy Department research lab in Golden, Colo.
"The real difference is in policy issues," he says. "The Europeans have decided that greenhouse gases are a serious problem, so they are willing to pay a premium to develop clean energy and avoid those emissions."
The development and introduction of new energy technologies is enormously expensive. From nuclear power to ethanol to gas turbines, the US government has invested billions to develop and bring new technologies to market.
Renewable-energy proponents say the countries that dominate the emerging wind- and solar-energy technologies will be those that foster growth through public investments, including government research spending, and tax incentives.
Past investments have lowered the cost of wind-generated electricity in the US from nearly 40 cents per kilowatt hour in 1980 to between 4 and 6 cents today.
But with oil and gas prices near historic lows, analysts say production costs must fall to 2.5 cents to compete with gas-fired turbines. The new Energy Department initiative is designed to help bridge the gap through grants, a renewal of a decade-old production tax credit, and increased research-and-development spending.
"If we are going to address climate-change challenges, we need to develop zero-pollution energy solutions," says Richardson. "Growth of wind power is good for the environment and good for the economy."
The US has enormous potential wind resources, enough to theoretically meet the entire country's energy needs, according to Dr. Thresher.
Limitations to widespread use
In reality, wind could probably never provide more than 10 or 20 percent of the nation's supply. It's impossible to know exactly how much power a given turbine will generate at a given time.
The electrical grid is supplied by a combination of "base-load" plants - usually coal- or nuclear-fueled - that run constantly, and "intermediate" and "peak" plants that are turned off during times when demand falls.
Wind energy can be stored by, say, pumping water uphill and releasing it during peak hours to drive turbines, but can't really replace base-load plants. The windiest places are also often far from places where energy demand is greatest. In the US, wind resources are concentrated in the Great Plains and in California's mountain passes. Transmission lines are costly.
A wind farm in Altamont Pass, Calif., was placed in an area frequented by eagles and other birds. It generated controversy when a study found some 200 had been killed by hitting turbines.
In other places, new wind projects have the support of farmers, who can lease land for turbines.
"It generates extra incomes [and] creates good, well-paying manufacturing jobs," says Worldwatch's Mr. Flavin. "It's not every day that you have a new manufacturing sector that's growing by 30 percent a year, and it's to the country's benefit to see that growth continue."