The demand for "green" electricity — electricity produced from renewable sources like wind, solar, hydropower, geothermal, and biofuels — is at an all-time high in the U.S. Over the past decade, solar and wind capacity have increased dramatically due largely to mandatory renewable portfolio standards (RPS), which have now been adopted by 27 states.

The environmental community strongly supports the use of RPSs to encourage investment in wind and solar power because of concerns about global warming and air pollution associated with traditional power plants. As wind turbines and solar facilities have proliferated, however, the environmental impacts of these "clean" fuels have come into focus. The result is a dilemma for environmentalists and a challenge to conventional notions of what constitutes a "green technology."

Renewable Energy Is Poised for Strong Growth

Over the past decade, wind power capacity quadrupled in response to strong demand. Solar power also expanded rapidly: It increased by 9% in 2007 and another 17% in 2008. Even with this dramatic growth, less than 5% of U.S. electric power currently comes from renewable fuels.

The Obama administration has made the expansion of wind and solar power a cornerstone of its energy policy with the goal of doubling renewable energy capacity by 2012. Congress provided unprecedented public investment through the economic stimulus package last year, as well as tax credits and incentives. Finally, the administration has signaled its willingness to allow extensive swaths of public land to be used for renewable energy and transmission lines, over the protests of advocates for parks, wildlife, and wilderness.

Wind and Solar Energy’s Environmental Challenges

Environmentalists find themselves in a quandary: On the one hand, they embrace the unparalleled government commitment to "clean" energy, while on the other hand they protest the impact of turbines and solar panels on rare plants and animals and water resources. How to reconcile these positions and not be perceived, as usual, as obstructionists to "progress," especially environmental progress?

Most environmental concerns about wind and solar energy boil down to concerns about siting. Rural landowners complain that wind turbines located on adjacent property obstruct their views and interfere with the "rural character" of the landscape. Coastal landowners — think expensive Cape Cod beach houses — object to offshore wind turbines in their field of vision. Wildlife advocates are concerned about the thousands of birds and bats killed annually by the blades of wind turbines located in migratory flyways and the habitat fragmentation that results from the development of wind and solar plants and transmission. Municipal, state, and federal regulators are alarmed by proposals to develop solar facilities in the arid (but sunny!) Southwest because the standard parabolic trough and central tower systems associated with many solar facilities use conventional steam plants to generate electricity — a process that uses more than twice as much water per kilowatt-hour as a coal-fired power plant.

Until recently, regulators did not pay much attention to the aesthetic and environmental impacts of renewable energy facilities. Several recent developments suggest that the pendulum may be shifting, which is likely to result in more expense for renewable energy developers. In Kansas, for example, one county enacted a land use ordinance in 2004 that banned completely all commercial wind farms. In response to a legal challenge, the Kansas Supreme Court upheld the county ordinance as reasonable, stating that it was justifiable for the county to base its land use restriction on scenic and aesthetic considerations and the wishes of some of the county residents.

Impacts to endangered species can also justify a legal challenge to renewable energy. In December 2009, a federal judge in Maryland ordered a halt to the construction of 122 wind turbines in the Appalachian mountains of West Virginia due to potential impacts on an endangered bat. The judge ordered the wind company to seek an "incidental take permit" before proceeding with construction, a process that is likely to take many months, if not years.

The conflict between alternative energy development and water resource protection is difficult to reconcile in some parts of the West. States with the greatest solar resources, such as Nevada, California, and Arizona, face overtaxed water supplies that are needed by municipalities, farmers, and endangered species. Federal agencies find themselves on opposite sides of the issue.

Dealing with the Tradeoffs of Using Renewable Energy

Where does all of this leave environmentalists and citizens interested in both sustainable energy and natural resource protection? What is called for is a more sophisticated understanding of and public discussion about the "dark side" of renewable power production. We need to recognize that there may be tradeoffs between wildlife and land protection and policies that promote rapid development of renewables. Above all, the situation calls for wise land use planning at multiple scales, particularly on public lands, to minimize the adverse environmental impacts of energy sources that have the potential to make key contributions to our energy security and solving the problem of global warming.

—Melinda E. Taylor ( teaches environmental law at the University of Texas School of Law in Austin, Texas, and is the executive director of the law school’s Center for Global Energy, International Arbitration, and Environmental Law.