For Energy-Hungry US, There Are Few Quick Fixes
VANCOUVER — Sunny Arizona and windswept Iowa seem like natural homes for solar and wind farms. But neither state shows up on a new renewable energy roadmap that shows exactly where solar and wind power can best satisfy the American hunger for energy.
Such surprising results for renewable energy come from a new study three years in the making. Researchers not only looked for the windiest or sunniest spots in the United States and around the world, but also examined whether a solar or wind farm could meet energy demand at the most urgent times of the day and year — especially during hot midsummer days.
"It's not good enough to just say 'where's the wind?'" said Alexander MacDonald, a deputy assistant administrator for the National Oceanic and Atmospheric Administration in Boulder, Colo. "If you want to design a [renewable energy] system, you want to design it so you're getting the resources that are available when you need them."
The ideal map for U.S. solar farms appeared clustered in southern California. By contrast, the ideal spots for U.S. wind farms appeared mostly in the high plains states such as South Dakota and Nebraska, with a few scattered offshore spots near the U.S. East Coast.
On a worldwide scale, the study found that solar and wind power could provide "reliable and smooth power" across a total area equivalent to half the size of the continental United States, MacDonald said.
Arizona didn't make the cut for solar power because its summer monsoon seasonoften leads to cloud-filled skies during hot summer afternoons when air conditioners roar at full blast. Many states also appeared less ideal for planting wind turbines because their winds blow strongest at night when energy demand is lower.
MacDonald pointed out that the study took into account many practical factors, such as not placing wind turbines in New York City's crowded Times Square, in national parks, or on the side of a steep mountain. He presented the study results at the annual meeting of the American Association for the Advancement of Science here in Vancouver today (Feb. 17).
The study used precise weather and atmospheric modeling that has become the standard for U.S. commercial airliners flying across the country. It also projected energy costs and demand through 2030 and accounted for energy sources such as natural gas (but not coal), so that it could figure out where renewable energy might make the most economic sense.
Such a study may prove a powerful tool for governments and companies worldwide when deciding how to best harness solar and wind power.
But putting solar and wind farms in the most ideal spots doesn't solve the problem of transmitting that power to consumers. China has the most installed wind power in the world, yet is struggling to build more power lines to connect its wind power to homes and businesses. U.S. wind power also faces the challenge of a transmission bottleneck on an aging U.S. power grid.
"The problem that has to be solved is basically the grid and transmission," MacDonald said. "If you do large-scale integration and bring the grid up, it can be cost-effective."