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GCB Bioenergy

Cover image for Vol. 9 Issue 4

Edited By: Steve Long

Impact Factor: 6.151

ISI Journal Citation Reports © Ranking: 2015: 1/83 (Agronomy); 9/88 (Energy & Fuels)

Online ISSN: 1757-1707

Associated Title(s): Global Change Biology

Legal analysis of biobutanol commercialization

Legal analysis of biobutanol commercialization

Biobutanol, a liquid fuel derived from the fermentation of feedstocks, is a promising emerging source of bioenergy. Slating and Kesan discuss how two regulatory regimes in the US simultaneously incentivize and hinder the commercialization of biobutanol, and how changes in these policies can progress bioenergy development.

Two advantages of biobutanol over first-generation biofuels (e.g., bioethanol) are outlined. First, biobutanol has higher energy content than bioethanol. This translates to greater fuel economy, which translates into greater gasoline displacement. Second, biobutanol is compatible with existing production and distribution infrastructure. Unlike bioethanol, which must be blended in low concentrations with gasoline to avoid damaging unmodified engines, biobutanol can act as a drop-in fuel, meaning that it can serve as a direct replacement to fossil fuels in unmodified gasoline engines.

The authors first discuss the federal Renewable Fuel Standard’s (RFS2) treatment of biobutanol, both currently and prospectively, and how it works to incentivize the commercialization of biobutanol. The RFS2 requires that the US fuel supply contain a minimum amount of biofuel that increases over time. This requirement is subdivided into specific volumetric mandates for unique categories of biofuels, which are referred to as “renewable fuel,” “advanced biofuel,” “cellulosic biofuel,” and “biomass-based diesel.” Each category is defined by the permissible feedstocks that a compliant biofuel can be derived from and a greenhouse gas (GHG) emissions reduction threshold (compared to gasoline or diesel, whichever the biofuel is intended to replace).

Because biofuel production is incentivized by the volumetric mandate for each category, when a given category’s mandate is satisfied, the incentive is lost. Although biobutanol is currently categorized as a “renewable fuel,” that category’s mandate will likely be met by corn ethanol. As such, in order for the RFS2 to efficiently incentivize the production of biobutanol, it must satisfy the more strict definition of “advanced biofuel” and/or “cellulosic biofuel,” which require a reduction in GHG emissions (compared to gasoline) by 50-60%, respectively. However, according to the Environmental Protection Agency’s (EPA) 2005 life-cycle assessment (LCA) for biobutanol, its use only results in a 31% GHG emissions reduction.

The authors give reasons why recent developments might result in new forms of biobutanol which could qualify as advanced biofuels or cellulosic biofuels and likely incentivize their production. First, the EPA’s 2005 LCA does not include new advances in the fermentation process that produce higher biobutanol yields and do not require energy intensive processes to separate the end-products. Second, recent research shows that US biofuels production has resulted in little indirect land use change, a factor that greatly contributed to the low calculated 2005 biobutanol GHG emissions reduction value. Third, the 2005 LCA is based on biobutanol produced from corn and new forms could be produced from other feedstocks with lower associated GHG emissions.

Next, the authors discuss how the Clean Air Act’s (CAA) regulations limit the potential biobutanol market, and how these regulations should be modified. The CAA prohibits the commercialization of any fuel or fuel additive that is not “substantially similar” to the EPA’s certification fuel (i.e., the fuel used to certify the emissions from vehicles and engines). This regulates the maximum amount of biobutanol that can lawfully be blended with gasoline. Higher blends can be commercialized if a waiver to the regulation is granted, but the waiver process is very costly, burdensome, and highly uncertain.

The authors suggest two ways that the CAA’s regulations could be reformed to support of the blending of fuel with higher concentrations of biobutanol. The EPA could revise its definition of “substantially similar” fuel and thereby increase lawful biobutanol blending limits. It could also mitigate the burdens associated with seeking new fuel waivers by providing a ‘fast-track’ review process for new fuel waivers involving biofuels that are capable of satisfying the RFS2’s mandates. The fast-track process would remove the public comment process and reduce the decision deadline.

Slating and Kesan believe that the suggested regulatory reforms could have profound impacts on the use of biobutanol and they encourage us to actively seek out regulatory reforms in order to facilitate the commercialization of socially beneficial biofuels.

Timothy A. Slating, Jay P. Kesan. (2012), A legal analysis of the effects of the Renewable Fuel Standard (RFS2) and Clean Air Act on the commercialization of biobutanol as a transportation fuel in the United States. GCB Bioenergy. doi: 10.1111/j.1757-1707.2011.01146.x Read this paper.

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