The Path to Cleaner Energy

Beyond bringing jobs to tens and eventually hundreds of thousands of Americans, can we expect wind energy to make a real difference in the way we fuel our economy? How much can we count on wind energy to rein in the pollution that is compromising our health and warming the Earth’s atmosphere? And what will it cost us to make wind a major part of our energy diet?

Looking at wind energy’s contribution today, it may seem premature—even presumptuous—to think of the technology as a game changer. During 2010, wind supplied 2.9 percent of America’s power needs. Coal, during the same period, delivered 45 percent of our electricity, and natural gas generated another 24 percent, followed closely by nuclear power, with a 20 percent share of overall output. Another 6 percent of our electricity came from conventional hydroelectric dams, while solar energy—photovoltaics and thermal systems combined—barely registered a blip on the screen at 0.03 percent.

From the broader vantage point of energy use across all sectors, wind’s current status looks humbler still. Electricity generation amounts to a little less than 40 percent of total U.S. energy consumption, with most of the rest relying on the direct burning of fossil fuels to run our vehicles, stoke our industries, and heat our buildings. So that means wind meets slightly more than 1 percent of our overall energy needs.

Wind energy’s role in weaning America off fossil fuels may be modest today, but its untapped potential is vast. In February 2010, the government-run National Renewable Energy Laboratory (NREL) released the results of a mapping effort that gauges the full magnitude of land-based wind energy as a resource that can serve America’s the path to cleaner energy power needs. First NREL identified “windy land areas,” which it defined as areas where the average winds are strong enough, at 80 meters (262 feet) above ground, to allow turbines to produce electricity at a minimum of 30 percent of their full installed or “nameplate” capacity, averaged annually. (A 30 percent “capacity factor” is considered moderately robust.) Areas with annual wind speeds averaging at least 14.6 miles per hour were regarded as meeting this threshold.

From this gross measure, NREL then subtracted territory that it deemed unlikely to be developed for wind because of conflicting uses or characteristics—urban areas, parks, designated wilderness, and areas with water features that could hinder wind development.

In my home state of Massachusetts, NREL rated less than 1 percent of the state as sufficiently windy, and it disqualified 88 percent of that small area because of conflicts. At the other end of the spectrum is Kansas, where almost 90 percent of the land meets the threshold for windiness, and only 10 percent of that windy area has been sidelined by NREL because of conflicts.

I remember loving those spin art kits that were toy store staples in the 1960s. After dribbling paints from ketchup-like dispensers onto a rectangular sheet of cardboard, I’d flip the switch of a battery-operated spinning wheel. Within seconds, a swirling, sometimes lurid maelstrom of colors emerged. On first glance, NREL’s digitized wind map of the United States reminds me of those creations. In the Southeast, spring green splashes across the Atlantic coastal states, reaching as far inland as Tennessee, Alabama, and eastern Mississippi.

This color connotes average wind speeds of less than 11.2 miles per hour—well below what’s needed to make wind a strong competitor with other power-generating fuels. Moving up into the Northeast, green yields to splotches of yellow and shades of brown, suggesting wind speeds edging up to 15 miles per hour. The same dappling of forest colors spreads from the Pacific Coast through Idaho, Utah, Nevada, and New Mexico. Then the real excitement begins. From the Rockies, across the Great Plains, stretching from eastern Montana and the Dakotas down to Texas, deep veins run from rust to violet to purple, plunging occasionally to midnight blue, revealing vast areas where average wind speeds range from 15 to 20 miles per hour. These expanses are the stuff of wind developers’ dreams.