As fossil fuel prices rise, as oil insecurity deepens, and as concerns about climate change cast a shadow over the future of coal, a new energy economy is emerging in the United States. The old energy economy, fueled by oil, coal, and natural gas, is being replaced by one powered by wind, solar, and geothermal energy. The transition is moving at a pace and on a scale that we could not have imagined even a year ago.

Consider Texas. Long the leading oil-producing state, it is now also the leading generator of electricity from wind, having overtaken California two years ago. Texas now has nearly 6,000 megawatts of wind-generating capacity online and a staggering 39,000 megawatts in the construction and planning stages. When all this is completed, Texas will have 45,000 megawatts of wind-generating capacity (think 45 coal-fired power plants). This will more than satisfy the residential needs of the state’s 24 million people, enabling Texas to feed electricity to nearby states such as Louisiana and Mississippi.

After Texas and California, the other leaders among the 30 states with commercial-scale wind farms are Iowa, Minnesota, Washington, and Colorado. And other states are emerging as wind superpowers. Clipper Windpower and BP are teaming up to build the 5,050-megawatt Titan wind farm, the world’s largest, in eastern South Dakota. Already under development, Titan will generate five times as much electricity as the state’s 780,000 residents currently use. This project includes building a transmission line along an abandoned rail line across Iowa, feeding electricity into Illinois and the country’s industrial heartland.

Colorado billionaire Philip Anschutz is developing a 2,000-megawatt wind farm in south central Wyoming. He already has secured the rights to build a 900-mile high-voltage transmission line to California. With this investment, the door will be opened to developing scores of huge wind farms in Wyoming, a wind-rich state with few people. Another transmission line under development will run north-south, linking eastern Wyoming’s wind resources with the fast-growing Colorado cities of Fort Collins, Denver, and Colorado Springs. Wind-rich Kansas and Oklahoma are looking to build a transmission line to the U.S. Southeast to export their wealth of cheap wind energy.

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California is developing a 4,500-megawatt wind farm complex in the Tehachapi Mountains northwest of Los Angeles. In the east, Maine — a wind energy newcomer — is planning to develop 3,000 megawatts of wind-generating capacity, far more than the state’s 1.3 million residents need. Further south, Delaware is planning an offshore wind farm of up to 600 megawatts, which could satisfy half of the state’s residential electricity needs. New York State, which has 700 megawatts of wind-generating capacity, plans to add another 8,000 megawatts, with most of the power being generated by winds coming off Lake Erie and Lake Ontario. And soon Oregon will nearly double its wind generating capacity with a 900-megawatt wind farm in the wind-rich Columbia River Gorge.

Wind appears destined to become the centerpiece of the new U.S. energy economy, eventually supplying several hundred thousand megawatts of electricity.

Solar power is also expanding at a breakneck pace. The nation’s wealth of solar energy is being harnessed by using both photovoltaic cells and solar thermal power plants to convert sunlight into electricity. For solar cell installations, California, with its Million Solar Roofs plan, is far and away the leader. New Jersey is also moving fast, followed by Nevada.

The largest U.S. solar cell installation today is a 14-megawatt array at Nellis Air Force Base in Nevada, but photovoltaic electricity at the commercial level is about to go big time. PG&E has entered into two solar cell power contracts with a combined capacity of 800 megawatts. Together, these plants will cover 12 square miles of desert with solar cells and will have a peak output comparable to that of a large coal-fired power plant. Solar power plants are appealing in hot climates because their highest output coincides with the peak demand for air conditioning.

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Solar thermal plants that use mirrors to concentrate sunlight on a vessel containing a fluid — heating it to 750 degrees Fahrenheit to generate steam and produce power — have suddenly become an enormously attractive technology. The United States has the world’s only large solar thermal complex, a 350-megawatt project completed in 1991. But as of September 2008 there are 10 large solar thermal power plants under construction or in development in the United States, ranging in size from 180 megawatts to 550 megawatts. Eight of the plants will be built in California, one in Arizona, and one in Florida. Within the next three years, the United States will likely go from 420 megawatts of solar thermal generating capacity to close to 3,500 megawatts — an eightfold jump.

Along with wind and solar, geothermal energy is also developing at an explosive rate. As of 2008 the United States has nearly 3,000 megawatts of geothermal generating capacity, 2,500 of which are in California. Suddenly this too is changing. Some 96 geothermal power plants now under development in twelve western states are expected to double U.S. geothermal generating capacity. With California, Nevada, Oregon, Idaho, and Utah leading the way, the stage is set for the massive future development of geothermal energy. (See data).

The new energy economy will be powered largely by electricity from renewable sources. Electricity will light, heat, and cool buildings. As we shift to plug-in hybrid cars, light rail transit systems in cities, and high-speed electric intercity rail systems like those in Japan and Europe, our transport system will also be powered largely by electricity.

It is historically rare for so many interests to converge at one time and in one place as those now supporting the development of renewable energy resources in the United States. To begin with, shifting to renewables increases energy security simply because no one can cut off the supply of wind, solar, or geothermal energy. It also avoids the price volatility that has plagued oil and natural gas in recent decades. Once a wind farm or a solar thermal power plant is built, the price is stable since there is no fuel cost. Turning to renewables will also dramatically cut carbon emissions, moving us toward climate stability and thus avoiding the most dangerous effects of climate change.

The shift also will staunch the outflow of dollars for oil, keeping that capital at home to invest in the new energy economy, developing national renewable energy resources and creating jobs here. At a time of economic turmoil and rising joblessness, these new industries can generate thousands of new jobs each week. Not only are the wind, solar, and geothermal industries hiring new workers, they are also generating jobs in construction and in basic supply industries such as steel, aluminum, and silicon manufacturing. To build and operate the new energy economy will require huge numbers of electricians, plumbers, and roofers. It will also employ countless numbers of high-tech professionals such as wind meteorologists, geothermal geologists, and solar engineers.

To ensure that this shift to renewables continues at a rapid rate, national leadership is needed in one key area — building a strong national grid. Although private investors are investing in long-distance high-voltage transmission lines, these need to be incorporated into a carefully planned national grid, the electrical equivalent of President Eisenhower’s interstate highway system, in order to unleash the full potential of renewable energy wealth.

And, finally, this energy transition is being driven by an intense excitement from the realization that people are now tapping energy sources that can last as long as the earth itself. Oil wells go dry and coal seams run out, but for the first time since the industrial revolution we are investing in energy sources that can last forever. This new energy economy can be our legacy to the next generation.

This post was created for the Earth Policy Institute.