To counter misinformation on renewables in the media, this article is recommended by Prof. Daniel Kammen, one of the lead authors of the Special Report on Renewable Energy Sources and Climate Change Mitigation of the Intergovernmental Panel on Climate Change (IPCC).
Land footprint seems an odd criterion for choosing energy systems: the amounts of land at issue are not large, because global renewable energy flows are so vast that only a tiny fraction of them need be captured. For example, economically exploitable wind resources, after excluding land with competing uses, are over nine times total national electricity use in the U.S.i and over twice in Chinaii; before land-use restrictions, the economic resource is over 6× total national electricity use in Britain and 35× worldwide—all at 80-meter hub height, where there’s less energy than at the modern ≥100 m.iii Just the 300 GW of windpower now stuck in the U.S. interconnection queue could displace two-fifths of U.S. coal power. Photovoltaics, counting just one-fifth of their extractable power over land to allow for poor or unavailable sites, could deliver over 150 times the world’s total 2005 electricity consumption,iv The sunlight falling on the Earth every ~70 minutes equals humankind’s entire annual energy use. An average square meter of land receives each year as much solar energy as a barrel of oil contains, and that solar energy is evenly distributed across the world within about twofold.v The U.S., “an intense user of energy, has about 4,000 times more solar energy than its annual electricity use. This same number is about 10,000 worldwide<, so> ...if only 1% of land area were used for PV, more than ten times the global energy could be produced....”vi
Nonetheless, many nuclear advocatesvii argue that renewable electricity has far too big a land “footprint” to be environmentally acceptable, while nuclear power is preferable because it uses orders of magnitude less land. If we assume that land-use is an important metric, a closer look reveals the opposite is true.viii
For example, Stewart Brand’s 2010 book Whole Earth Discipline cites novelist and author Gwyneth Cravens’s claim that “A nuclear plant producing 1,000 megawatts takes up a third of a square mile.” But this direct plant footprint omits the owner-controlled exclusion zone (~1.9–3.1 mi2).ix Including all site areas barred to other uses (except sometimes a public road or railway track), the U.S. Department of Energy’s nuclear cost guidex says the nominal site needs 7 mi2, or 21× Cravens’s figure. She also omits the entire nuclear fuel cycle, whose first steps—mining, milling, and tailings disposal—disturb nearly 4 mi2 to produce that 1-GW plant’s uranium for 40 years using typical U.S. ores.xi Coal-mining to power the enrichment plant commits about another 22 mi2-y of land disturbance for coal mining, transport, and combustion,xii or an average (assuming full restoration afterwards) of 0.55 mi2 throughout the reactor’s 40-y operating life. Finally, the plant’s share of the Yucca Mountain spent-fuel repository (abandoned by DOE but favored by Brand) plus its exclusion zone addsxiii another 3 mi2. Though this sum is incomplete,xiv clearly Brand’s nuclear land-use figures are too low by more than 40-foldxv—or, according to an older calculation done by a leading nuclear advocate, by more than 120-fold.xvi
This is strongly confirmed by a new, thorough, and authoritative assessment ...
Renewable Energy's "Footprint" Myth AUTHOR:
, AmoryDOCUMENT ID: E11-07
YEAR: 2011
DOCUMENT TYPE: Journal or Magazine Article
PUBLISHER:
The Electricity JournalYou can download for free the author's prepublication copy here:
http://www.rmi.org/rmi/Library/2011-07_RenewableEnergysFootprintMyth
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