A expansão territorial da energia

The New York Times
August 26, 2009, 8:22 am — Updated: 1:41 pm -->
Study Warns of ‘Energy Sprawl’
By Kate Galbraith

A paper published on Tuesday by the Nature Conservancy predicts that by 2030, energy production in the United States will occupy a land area larger than Minnesota — in large part owing to the pursuit of domestic clean energy.
“Saving energy saves land. There’s a real link there.”
— Robert McDonaldThe Nature Conservancy
The authors call it “energy sprawl” — a term meant to draw attention to habitat destruction, and to warn that biofuels in particular will take up substantial amounts of land.
“There’s a good side and a bad side of renewable production,” said Robert McDonald, a Nature Conservancy scientist and one of the authors, in a telephone interview.
The paper looked at several scenarios, including a “base-case” derived from current Energy Information Agency forecasts for the country’s energy mix in 2030, as well as various permutations of efforts to cap greenhouse gas emissions to combat climate change.
The study took into account only land impacts in the United States; thus for example the land required to drill for oil in Saudi Arabia, one of the United States’s biggest suppliers, was not considered. Nor was “indirect land use” taken into account. That is the controversial idea that growing soy for fuel in the United States could simply push soy-for-food production to, say, Indonesia, where CO2-sipping forests would then be razed for soy farming.
Nuclear power is the most compact in terms of the amount of land taken up per unit of energy, according to the study; coal and geothermal energy also took up relatively small amounts of space. Biodiesel made from soybeans, the burning of energy crops to create electricity, and ethanol production had the highest “sprawl” impact.
Asked about the assertion by some solar advocates that covering a 100-mile by 100-mile square of Nevada desert with solar arrays could power the United States, Mr. McDonald said that the study was “trying to avoid that kind of maximal estimate,” and be more realistic about the projected energy mix.
As for climate change, Mr. McDonald said that the Nature Conservancy believes that this is “something humanity absolutely has to deal with,” and the paper highlights several ways to reduce the sprawl. These include reusing already-developed sites, as well as a flexible cap-and-trade system that allows for the development of new nuclear plants and the sequestration of carbon dioxide emissions from coal plants.
But perhaps the most important is energy conservation.
“Saving energy saves land,” Mr. McDonald said. “There’s a real link there.”