Birds Landing, Calif. ? Environmentalists say the dozens of turbines that rise more than 300 feet over wheat fields and herds of sheep here represent the future of wind energy — and a model for overcoming the shortcomings that have kept wind from threatening the dominance of fossil fuels.

The High Winds Energy Center, completed in December in the rolling hills between San Francisco and Sacramento, features turbines that can swivel with the direction of the wind, produce energy even if the wind is blowing less than 8 mph and generate 20 times more energy than earlier machines.

This new wind system, along with similar ones being built around the country, promises to produce electricity at competitive prices — all without disturbing surrounding farms and wildlife, two of the obstacles for wind power today.

The 90 turbines at High Winds can generate 162 megawatts of electricity, enough to power about 75,000 homes, according to Florida-based FPL Energy, which owns and operates High Winds along with 30 other wind facilities in 10 states.

“This is the future of wind power,” said Ralph Cavanagh, energy program director for the Natural Resources Defense Council. “The wind farm is becoming a productive part of the local community. It’s not an interloper that threatens them.”

Environmentalists have championed wind power for decades because wind is a free, renewable resource that doesn’t pollute the air or water.

But since the first large wind facilities were built in the early 1980s, they have run into technological, economic and political barriers. Early versions didn’t produce electricity efficiently enough to compete with oil, coal and natural gas. Communities complained that small forests of turbines marred the landscape, and environmentalists fretted that the blades were killing birds.

The new wind farm, set in the Montezuma Hills above six farms and ranches just north of the Sacramento River, has overcome such issues, environmentalists say.

High Winds’ turbines are taller, more powerful and more efficient than older generation turbines, which means they can generate more energy with fewer machines. Each turbine generates 1.8 megawatts, 18 times more than the 100-kilowatt turbines built two decades ago.

On a recent morning, the towering turbines’ 125-foot blades turned steadily, with surprisingly little noise, in wind of about 10 mph.

An old windmill, right, shares space with new, state-of-the-art windmills in Birds Landing, Calif. A forest of 300-foot-high turbines spins electricity for a half a dozen California cities on the wind farm in rural Solano County, between San Francisco and Sacramento.

Older turbines can’t rotate from side to side — and they only operate at maximum efficiency when the wind blows in a particular direction, so they often remain idle. High Winds’ turbines can rotate to face oncoming breezes and capture energy at wind speeds from 8 to 55 mph, said FPL spokesman Steven Stengel.

Their increased height, longer blades and improved positioning also lets them better tap the wind’s power. While older turbines break down often and require constant repair, newer versions are more durable.

Many wind farms built in the 1980s are retiring old machines and replacing them with newer, more efficient models similar to those at High Winds, whose turbines were developed by Denmark-based Vestas Wind Systems.

High Winds hasn’t run into the kind of opposition plaguing other wind energy projects, such as the offshore towers proposed near Massachusetts’ Cape Cod, where residents worry that 40-story turbines would harm ocean views, seabirds and tourism.

In fact, landowners in the agricultural Montezuma Hills welcome the extra income — FPL pays between $2,500 and $4,000 a year to lease the space for each turbine, while the surrounding land can still be used raise animals, grow crops and other activities.

Birds Landing farmer Ian Anderson said the turbines and the roads built to service them take up about 2 percent of his farmland, leaving the remaining 98 percent available for raising sheep and growing wheat, barley and safflower. He calls the project “good for society.”

“It’s more difficult to farm around (the turbines and roads), but it’s not overwhelming. It’s doable,” he said. “We’re still farming the same as before the wind generators came in.”

And unlike the wind farm in the Altamont Pass east of San Francisco, where smaller, low-power turbine blades have killed an estimated 22,000 birds, High Winds’ turbines rotate more slowly, so few birds get caught.

Projects like High Winds have benefited from government incentives such as federal tax credits. About a dozen states, including California, require utilities to increase their use of renewable sources such as wind, solar and geothermal energy.

Environmentalists hope that the incentives and improved technologies will boost wind from its status as a minor player in the U.S. energy markets. Even in California, which leads the nation in use of wind power, less than 2 percent of the state’s electricity came from wind in 2002, according to the California Energy Commission.

“With improvements in technology, wind power is becoming cost competitive with any other form of electrical generation,” said Jan Johnson, a spokeswoman for PPM Energy, an energy wholesaler that has already sold two-thirds of High Winds’ output to cities including Anaheim, Pasadena, Glendale and Sacramento.

PPM wouldn’t disclose specific energy prices it charges its customers.

But Johnson noted that wind prices are far less volatile than those for fossil fuels. And unlike with natural gas, PPM can offer energy contracts as long as 25 years because wind has no fuel costs.

“If you have a choice between any form of electrical generation,” she said, “are you going to choose one that generates greenhouse gases or wind power?”