I Say Sustainable, You Say…

The Guardian newspaper reported last week that environmental activist and reporter George Monbiot had successfully petitioned Britain’s Advertising Standards Authority (ASA) to ban an ad containing the tagline, “Biofuels — A Lower-Priced, Sustainable Answer to OPEC’s Oil.” The ad was sponsored by the Renewable Fuels Association, the Canadian Renewable Fuels Association, the European Bioethanol Fuel Association, and the Brazilian Sugarcane Industry Association.

Though Monbiot’s petition is not publicly available, the ASA’s adjudication response indicates it is similar to his previously expressed opinion that “there is no such thing as a sustainable biofuel.”

Monbiot, of course, bases this conclusion in part on the paper published by Searchinger et al. in SciencExpress last February. Monbiot, like many others, believes that this paper proves that biofuels production causes shifts in land use that increase greenhouse gas emissions. In point of fact the paper starts from an assumption that shifts in land use are caused by biofuels production. It therefore cannot be taken as proof. The paper states its assumptions clearly enough:

Although these estimates face several uncertainties, the general finding flows from three reliable projections. First, farmers will replace most of the grain diverted from food and feed by ethanol because the demand for overall food and feed — as opposed to any particular grain — is inelastic. Second, increases in cropland will provide most replacement grain because they are cost-effective and fast, the yield effects of biofuel demands are both positive and negative, and the world has many convertible acres – up to 170 million hectares in Brazil alone and perhaps 2.8 billion hectares worldwide. Most significantly, the potential emissions per hectare of land conversion greatly exceed the annual greenhouse reductions per hectare of biofuels.

The ASA banned the ad’s use of the word “sustainable” in part on a misinterpretation of the conclusions of “The Gallagher Review of the indirect effects of biofuels production.” The ASA’s adjudication incorrectly states that “the review considered biofuel production would result in net greenhouse emissions and loss of biodiversity through habitat destruction in the period to 2020.”

In fact, the Gallagher review states, “the balance of evidence shows a significant risk that current policies will lead to net greenhouse gas emissions and loss of biodiversity through habitat destruction.” The review includes the Searchinger paper in the balance of evidence, but clearly recognizes that it can not be considered proof that biofuels cause indirect land use emissions. The review’s conclusions include a clear statement that “Mechanisms do not yet exist to accurately measure, or to avoid, the effects of indirect land-use change from biofuels.”

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UK Study Highlights Uncertainty in Calculating Indirect Land Use Emissions

Britain’s Renewable Fuels Agency this week released the Gallagher Review, a report on the indirect effects of biofuels production that was prompted by the Searchinger and Fargione studies published in Science earlier this year. (See this blog’s earlier post on the forthcoming study.)

The summary of the conclusions of the Gallagher Review include some very telling comments:

Quantification of GHG emissions from indirect land-use change requires subjective assumptions and contains considerable uncertainty.
“Current lifecycle analyses of GHG-effects fail to take account of indirect land-use change and avoided land use from co-products.
“Mechanisms do not yet exist to accurately measure, or to avoid, the effects of indirect land-use change from biofuels.”

Where does the uncertainty identified by the Gallagher Review in the Searchinger and Fargione models come from? Factors include the complex global nature of agricultural markets, the potential for a variety of biofuel feedstocks, production of co-products from the same feedstocks, and the prices of commodities.

According to the Gallagher Review, the model proposed by Searchinger cannot accurately predict future demand for commodities and how global markets will respond. The review notes that agricultural production of food and feed was already shifting from America and Europe to other parts of the world. U.S. and EU biofuel policies were a response to this shift intended to provide new markets for agricultural production.

Searchinger’s model also does not account for future productivity or increases in yield –- he assumes there will be no increase in yield. The model similarly does not take into account increases in productivity from biofuel production technology.

Further, Searchinger does not accurately account for uncertainties in the amount of greenhouse gas emissions that occur from land-use change. Professor Bruce Dale of Michigan State University has previously noted the difficulty in assessing emissions from land-use change. BIO’s 2006 study on Achieving Sustainable Production of Agricultural Biomass shows that adoption of no-till agriculture, which has been increasing, can reduce greenhouse gas emissions and even store additional carbon in soil, a fact that the Gallagher Review makes note of.

As a result, the Gallagher review disputes Searchinger’s calculation of a 167-year carbon debt for U.S. ethanol production, stating, “This review has been unable to definitively assess the accuracy of the Searchinger calculation for the GHG emissions arising from US maize ethanol.”

The studies conclusion for future policy is that biofuels have the potential to reduce greenhouse gas emissions and that policy should encourage innovation and new technologies that increase that potential.