Nuclear Energy Insight
September 2010—Imagine that you’re the head of a task force in a Western state that has the goal of significantly cutting carbon emissions by 2030. Among the things you’d want to know is which low-carbon options produce the most energy on the least amount of land. Even in a big state, the population is going to grow quickly—America’s population is shifting to the West and South.
You also have to preserve iconic Western landscapes—the deserts, prairies, mountains and forests—and local habitats for future generations.
So which energy generator uses the least space to produce the most electricity? According to a new study to appear this fall, the answer is nuclear energy. “It was not surprising to us that nuclear had such a small footprint,” said Clinton Andrews, professor of urban planning at the Bloustein School of Planning and Public Policy at Rutgers University and lead author of the report. “It’s got such an incredible power density.”
The study, “Alternative Energy Sources and Land Use,” will appear as a chapter in a book issued by the Lincoln Institute of Land Policy this fall. With the growth of renewable technologies like wind, solar and biofuels, there has been increasing interest in the land requirements of these energy sources. Some renewables may adversely affect habitats because of their high land-use requirements, a phenomenon known as “energy sprawl.” Highly visible wind farms are one example of energy sprawl.
Andrews’ study uses a methodology from an earlier study (by Robert McDonald et al., 2009) to weigh energy options based on their “energy yield per square kilometer.”
“Land intensity can be measured using the land area (km2) required to deliver a standard amount of economically useful energy (terawatt hours per year or TWh-year),” the report says. The report goes on to rank energy sources by their land requirements needed by 2030 (see chart).
Land Use Intensity: The values represent estimated energy production by nuclear and renewable energy sources in 2030, measured in km2 of affected area per terawatt-hour produced in that year. By this measure, coal is 9.7, natural gas 18.6, and petroleum 44.7.
“The big surprises for us were actually how well solar thermal did, that there was actually a renewable in the same category as nuclear. Definitely, nuclear came out very well,” Andrews said.
Andrews explained that the study attempted to factor in each fuel’s land needs over its entire life cycle. This includes land used for mining, support infrastructure, transportation routes and waste repositories. In the case of nuclear energy, this included “land devoted to uranium mining and Yucca Mountain as well as the plants themselves,” Andrews said. (Yucca Mountain, originally planned as a federal repository for used nuclear fuel, has received no funding in the fiscal 2011 budget. A high-level commission is exploring options for dealing with used fuel.)
However, the land use totals do not include electric transmission lines, Andrews said. This could greatly increase the land use requirements of wind and solar power, both of which tend to be sited in areas far from urban centers and the electric grid.
Andrews sees biofuels’ land needs as especially problematic.
“[Biofuels] are unrealistic as the big solution to anything just because of their land intensiveness, but that doesn’t mean they don’t have a valuable niche role. The niches that I see are things like waste to energy ... and substituting for certain liquid fuels in transportation. You can’t run airplanes on electricity.”
Another conclusion of the study was that distributed generation—in which each locale uses small power sources to essentially power itself—will not be enough to meet the nation’s long-term energy needs. Instead, distant renewable resources and long transmission lines will be needed to get electricity to consumers.
“The most important question for me was: Do we need all these new transmission lines? The conclusion we came to was: I’m afraid we do need the transmission after all. We’re not going to get there with just distributed generation on rooftops.”
—Read more articles in Nuclear Energy Insight and Insight Web Extra.