Effects of US Maize Ethanol on Global Land Use and Greenhouse Gas Emissions: Estimating Market-mediated Responses

TitleEffects of US Maize Ethanol on Global Land Use and Greenhouse Gas Emissions: Estimating Market-mediated Responses
Publication TypeJournal Article
Year of Publication2010
AuthorsHertel T, Golub AA, Jones AD, O'Hare M, Plevin RJ, Kammen DM
JournalBioScience
Volume60
Issue3
Pagination223 - 231
Date Published03/2010
ISSN1525-3244
Keywordsbiofuels, ethanol, greenhouse gas emissions, land-use change, market-mediated effects
Abstract

Releases of greenhouse gases (GHG) from indirect land-use change triggered by crop-based biofuels have taken center stage in the debate over the role of biofuels in climate policy and energy security. This article analyzes these releases for maize ethanol produced in the United States. Factoring market-mediated responses and by-product use into our analysis reduces cropland conversion by 72% from the land used for the ethanol feedstock. Consequently, the associated GHG release estimated in our framework is 800 grams of carbon dioxide per megajoule (MJ); 27 grams per MJ per year, over 30 years of ethanol production, or roughly a quarter of the only other published estimate of releases attributable to changes in indirect land use. Nonetheless, 800 grams are enough to cancel out the benefits that corn ethanol has on global warming, thereby limiting its potential contribution in the context of California’s Low Carbon Fuel Standard.

DOI10.1525/bio.2010.60.3.8
Short TitleBioScience
AttachmentSize
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