Over millennia, plants and animals have adapted to changing climates by migrating to more favorable locales. If the climate continues to change in a manner consistent with current expectations, most warming will occur in the high latitudes. In order for plants and animals to adapt, large areas of habitat, especially those along north-south gradients, must be available for movement.

This has direct implications for future energy policies. Specifically, we should carefully consider the footprint our choices imply. In terms of sparing landscapes, energy sources with high energy densities (i.e., the amount of energy per unit of volume or mass) are important. Just as high-yield agriculture reduces pressure to convert native ecosystems to cropland, high-density fuels make it possible for the roughly 60 million residents of the United Kingdom to live on a small island while still protecting nearly a quarter of England’s landscape in National Parks and Areas of Outstanding Natural Beauty. Regarding electricity production, today only two sources fit this bill: fossil fuels and nuclear power.

I’ve frequently criticized diffuse sources of energy, especially wind power. This is despite the fact that FREE receives support from GE, the world’s largest installer of wind turbines. I believe wind advocates uncritically promote it as a panacea with little understanding of the energy realties we face or the trade-offs wind implies. For example, Al Gore urges us to “produce every kilowatt of electricity through wind, sun, and other Earth-friendly energy sources within 10 years. This goal is achievable, affordable, and transformative.” It’s not. Those claiming otherwise are unhinged; their version of reality is unattainable.

Let’s look at a more modest goal; a DOE report claiming 20 percent of U.S. electricity demand can be met from wind by 2030. To meet this goal will require that the U.S. install as much wind power as it has in its entire history each and every year between 2018 and 2030. Since the wind is intermittent, to avoid using natural gas peaking units to backup the load, wind’s cumulative share of electricity generation will likely have to reach about 40 percent. Today it’s 0.2 percent. Despite this, the DOE’s goal is possible given: (1) political determination to overcome the outrage over higher electricity bills, (2) a huge commitment of resources, and (3) discounting to zero the forgone opportunities.

For wind energy to contribute in any meaningful way requires the consumption of huge amounts of land. A 1000 MW nuclear or coal plant occupies approximately one square mile of land. To produce the same amount of electricity from a wind farm requires about 125 square miles. Oil man T. Boone Pickens proposes building wind turbines stretching from the Texas panhandle to the Canadian border. And much more land will be needed to construct a new electric grid to move the energy to where people are. (To meet 2005 U.S. electricity demand with around-the-clock-wind would required wind farms covering a landscape the size of Texas plus Louisiana.)

Jessie Ausubel of Rockefeller University has persuasively argued for years that we are steadily de-carbonizing our primary sources of energy, gradually moving toward a hydrogen economy. He writes, “Technologies succeed when economies of scale form part of their conditions of evolution. Like computers, to grow larger, the energy system must now shrink in size and cost.... The extraordinary energy density of nuclear fuel allows compact systems of immense scale, and...suits the ever-higher spatial density of energy consumption at the level of the end user, logically matching energy consumption and production.”

Every energy source carries environmental trade-offs. Solar and wind energy are extremely dilute and it’s expensive (on multiple dimensions) to capture and transform this “free” energy into useful forms. Dams eventually fill with silt. Fossil fuels warm the climate and pollute the air, and nuclear power plants produce hazardous wastes. The choices we face involve balancing competing values. This is the ignored reality.