For a country with a reputation for being addicted to fossil fuels, it may come as a surprise that the United States is now the world leader in one green-energy category.

During the first half of 2008, the U.S. surpassed Germany in total amount of electricity generated from the wind, according to the American Wind Energy Association.

And San Diego and Riverside counties are playing a role in wind power's rise in this country.

Germany still has the ability to generate more electricity at any given moment, but the U.S. is getting more out of its windmill-like turbines, said Ryan Wiser, a scientist at Lawrence Berkeley National Laboratory who tracks wind power.

"America is sort of a Saudi Arabia of wind," said Jim Walker, association president and vice chairman of enXco, an Escondido-based green energy developer, in a telephone interview Thursday. "It's got much better wind -- higher wind speeds."

As a result, U.S. turbines churn out electricity about 30 percent of the time compared to 20 percent of the time in Germany, Walker said, and are generating more power.

At the same time, the U.S. is adding turbines three times as fast as Germany and soon -- within a year or two -- will possess the world's largest wind generation capacity.

The trend, while far from proof the U.S. is cured of its addiction, is an indication the country is moving aggressively toward a greener future at a time when there is growing concern about the potential for global warming to cause far-reaching damage.

Climate scientists, a large majority of whom believe there is a connection between greenhouse gases such as carbon dioxide and the changing climate, warn that California could be hit by coastal flooding, hotter and smoggier summers, more and larger wildfires, and shrinking water supplies.

'Tip of the iceberg'

Regional economists say San Diego and Riverside counties also could benefit from the trend because one of the state's biggest wind farms is along Interstate 10 near Palm Springs and one of the areas with the biggest potential for new wind farms is along Interstate 8 east of San Diego.

San Diego Gas & Electric, for example, developed 50 megawatts of wind power recently on land owned by the Campo Band of Kumeyaay Indians.

And, said Walker, whose company operates 3,800 turbines throughout the country, "The Kumeyaay project is really the tip of the iceberg."

According to the utility's Web site, the utility that provides electricity to 3.5 million people in San Diego County and southern Orange County has signed contracts to secure up to 356 megawatts of power from turbines in San Diego, Riverside and Kern counties.

Jennifer Briscoe, a company spokeswoman, said the firm is trying to wind up a contract for 210 additional megawatts of wind power.

To place those numbers in perspective, San Diego-area residents use nearly 5,000 megawatts to light and cool homes and offices on the hottest summer days.

A megawatt is the amount of electricity it takes to power 650 homes, according to the San Diego utility.

The new focus on the wind is moving the utility closer to meeting a state mandate of providing 20 percent of its power from green renewable sources, though company officials have said they won't meet the 2010 target date.

Shifting winds

Southern California Edison, which provides electricity to customers in Riverside, Orange, Los Angeles and San Bernardino counties, among other areas, also is scrambling to meet the mandate, though it is farther along.

As of last year, 16 percent of its power came from green energy sources -- the most in the nation -- while just 6 percent of SDG&E's power came from such sources.

Mike Marelli, "manager of origination for renewable and alternative power" for Edison, said that one-fifth of the energy giant's green electricity comes from the wind.

Marelli said the company has about 1,000 megawatts of capacity, primarily from turbines in the Palm Springs area and in the Tehachapi Mountains north of Los Angeles.

By 2010, the utility plans to begin tapping a new, 1,500-megawatt wind project in the Tehachapis that will more than double the total.

Besides the major regional utilities, the military is getting into the act, too.

The U.S. Marine Corps on Friday broke ground on its first wind farm, one that will power its Marine Corps Logistics Base, Barstow, a supply and maintenance installation in the Mojave Desert of San Bernardino County.

The renewed interest in tapping one of Mother Nature's most powerful attributes follows a long lull in wind-power interest.

Walker said the United States actually was the world's wind-power leader briefly, in the early 1980s, because California then had one of the highest concentrations of turbines on the planet.

But not long after, Walker said, "when gas-fired power plants became very popular, we sort of lost focus and the Europeans took the lead -- Germany in particular."

Now the winds have shifted.

Renewed focus

"The United States has regained its focus on the need for renewable electric generation," he said. "It's time for a little celebration. We're back."

As a proportion of total electricity production, wind's contribution remains small -- less than 2 percent, according to a report compiled by Wiser and Mark Bolinger at the Lawrence Berkeley National Laboratory.

And in the European countries of Denmark (20 percent), Spain (12 percent), Portugal (9 percent), Ireland (8 percent) and Germany (7 percent), wind generation still makes a greater contribution to national power supplies than it does in the U.S.

But a U.S. Department of Energy study suggests that wind's share of U.S. power has the potential to soar as high as 20 percent.

Not everyone agrees, however, that wind is the way to go in the future. Critics suggest wind power is unreliable because, well, it is available only when the wind blows, and often that does not coincide with the period when electricity is needed most -- on hot summer days.

But Edison's Marelli said wind has the potential to offset much of the carbon dioxide that is being spewed into the atmosphere from natural-gas-fired plants throughout the year.

Yes, you need sources of power that can be called upon immediately on hot days, but you also need a variety of ways to curb greenhouse gas emissions, he said.

"It's like building a stock portfolio," Marelli said. "You wouldn't have all T-bills in your portfolio, and you wouldn't have all stocks in your portfolio."

Contact staff writer Dave Downey at (760) 745-6611, ext. 2623, or ddowney@nctimes.com.