Wind Energy

Wind Energy Tops 10 Percent Share of Electricity in Five U.S. States

A new picture is emerging in the U.S. power sector. In 2007, electricity generation from coal peaked, dropping by close to 4 percent annually between 2007 and 2011. Over the same time period, nuclear generation fell slightly, while natural gas-fired electricity grew by some 3 percent annually and hydropower by 7 percent. Meanwhile, wind farm generated electricity grew by a whopping 36 percent each year. Multiple factors underlie this nascent shift in U.S. electricity production, including the global recession, increasing energy efficiency, and more economically recoverable domestic natural gas. But ultimately it is the increasing attractiveness of wind energy as an energy source that will drive it into prominence.

Wind power accounted for just 2.9 percent of total electricity generation in the United States in 2011. In five U.S. states, however, 10 percent or more of electricity generation came from wind turbines. South Dakota leads the states, with wind power making up 22 percent of its electricity generation in 2011, up from 14 percent in 2010. In 2011, Iowa generated 19 percent of its electricity with wind energy. And in North Dakota, wind’s share was 15 percent.

The two most populous U.S. states are also harnessing more of their wind resources. While adding more than 900 megawatts of new wind farms in 2011 to its existing 3,000-megawatt wind farm capacity, California was able to increase its wind farm electricity share from 3 to 4 percent. Texas has the most wind turbines installations of all the states, with 10,400 megawatts. In fact, if Texas were a country, it would rank sixth in the world for total wind farm capacity. Figures from the Electric Reliability Council of Texas (ERCOT), the independent service operator that delivers 85 percent of the state’s electricity, show that wind’s share of electricity in the ERCOT region jumped from 2.9 percent in 2007 to 8.5 percent in 2011.

Even though the cost of generating electricity from the wind turbines has fallen substantially, certain policies have been needed to help it compete with the longtime support and lack of full-cost accounting for fossil fuels. Through so-called renewable portfolio standards (RPS), 29 states now require a percentage of utilities’ electricity to come from renewables by a certain date. This includes 8 of the top 10 states in total installed wind power capacity. For example, California’s RPS requires one third of the state’s electricity to come from renewable sources by 2020. But the biggest policy driver of U.S. wind power growth thus far has been the federal production tax credit (PTC) for each kilowatt-hour of electricity a wind turbines generates. When Congress has allowed the PTC to expire, as it is scheduled to do again at the end of 2012, wind farm installations in the following year have plummeted.

In the short term, extending the PTC will be critical for the U.S. wind turbines industry, which boasts more than 400 turbine component manufacturers and employs some 75,000 people. Ultimately, moving away from the recurring boom-bust threat by establishing a national RPS or a carbon tax would encourage even greater manufacturing growth and wind farm installations.

In a country where wind resources could power the entire economy, there is still great potential to be realized. Four states in northern Germany have set the mark, with each getting more than 40 percent of their electricity from the wind farm. Which U.S. state will get there first?

For more information and data on wind energy in the United States and around the world, see Earth Policy Institute’s Wind Indicator, “World Wind Power Climbs to New Record in 2011,” at www.earth-policy.org.

J. Matthew Roney, www.earth-policy.org