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Biofuel Blunders
Reference
Reijnders, L. 2011. The life cycle emission of greenhouse gases associated with plant oils used as biofuel. Renewable Energy 36: 879-880.

Background
The author writes that it is widely believed that "raw plant oils have considerable advantages over conventional, fossil fuel-based, diesel as regards life cycle greenhouse gas emissions," noting that studies that are typically cited to support this conclusion "focus on fossil fuel inputs in the plant oil life cycle," while reminding us that "greenhouse gas emissions linked to fossil fuel inputs are not the only greenhouse gas emissions associated with the plant oil life cycle."

What was done
Reijnders briefly reviews some recent keystone studies that pretty much prove his point.

What was learned
The University of Amsterdam researcher reports that with respect to obtaining palm oil from trees planted on recently deforested soil in Southeast Asia (Wicke et al., 2008), soybean oil from crops planted on recently deforested soil in Brazil (Reijnders and Huijbregts, 2008), and rapeseed oil from crops planted on existing arable soil in Europe (Reijnders and Huijbregts, 2008), it has been found that "the greenhouse gas emissions associated with the life cycle of the oils considered are larger than the corresponding emissions associated with conventional fossil fuel-based diesel." And he further reminds us that when there is a rapid expansion of oil crop production on existing arable soils, much of the shortfall in food and feed production "has to be met by expansion of agricultural land elsewhere," as noted by Searchinger et al. (2008); and he states that "this in turn may lead to changes of (agro) ecosystem carbon stocks, which give rise to net emissions of greenhouse gases." Reijnders also notes that in the case of palm oil, the time required to pay back the subsequent "carbon debt" is probably on the order of 60-100 years "when oil palms are cultivated on mineral soils after recent deforestation (Fargione et al., 2008; Gibbs et al., 2008) and on the order of more than one century to over nine centuries, when the oil palms are cultivated on peat (Gibbs et al., 2008; Danielsen et al., 2009; Wicke et al., 2008)." And when soybeans are cultivated for oil on recently deforested land, he says that "the carbon payback time is in excess of 300 years (Gibbs et al., 2008)."

What it means
In light of these several considerations, Reijnders concludes that "current plant oils such as European rapeseed oil, and soybean and palm oil from recently deforested soils have higher life cycle greenhouse gas emissions than conventional diesel." And, we hasten to add, the workers of the world are actually paying for this debacle ... and in more ways than one!

References
Danielsen, F., Beukema, H., Burgess, N.D., Parish, F., Bruhl, C., Donald, P.F., Murdiyarso, D., Phalan, B., Reijnders, L., Struebig, M. and Fitzherbert, E.B. 2009. Biofuel plantation on forested land: double jeopardy for biodiversity and climate. Conservation Biology 23: 348-358.

Fargione, J., Hill, J., Tilman, D., Polasky, S. and Hawthorne, P. 2008. Land clearing and the biofuel carbon debt. Science 319: 1235-1238.

Gibbs, H.K., Johnston, M., Foley, J.A., Holloway, T., Monfreda, C., Ramankutty, N. and Zaks, D. 2008. Carbon payback times for crop-based biofuel expansion in the tropics: the effects of changing yield and technology. Environmental Research Letters 3: 10.1088/1748-9326/3/3/034001.

Reijnders, L. and Huijbregts, M.A.J. 2008. Biogenic greenhouse gases linked to the life cycles of biodiesel derived from European rapeseed and Brazilian soybeans. Journal of Cleaner Production 16: 1943-1948.

Searchinger, T., Heimlich, R., Houghton, R.A., Dong, F.X., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D. and Yu, T.-H. 2008. Use of US croplands for biofuels increases greenhouse gases through emissions from land use change. Science 319: 1238-1240.

Wicke, B., Dornburg, V., Junginger, M. and Faaij, A. 2008. Different oil palm production systems for energy purposes and their greenhouse gas implications. Biomass and Bioenergy 32: 1322-1337.

Reviewed 16 March 2011