On February 19, the California Air Resources Board (CARB) held a public hearing on the California Low-Carbon Fuel Standard (LCFS). The standard, which mandates a 10 percent reduction in the carbon intensity of transportation fuels by 2020, has been on hold since 2013. CARB expects to formally adopt the new LCFS by this summer, with major changes expected to the annual reduction targets and how those targets are achieved. Many ethanol industry groups argue the proposed changes to the LCFS will unfairly penalize domestic ethanol producers in favor of Brazilian imports of sugar cane ethanol. The non-profit Energy Future Coalition (EFC) and the Urban Air Initiative (UAI) argue that not only is domestic ethanol the least costly option for reducing the carbon footprint of the transportation sector, but that mid-level ethanol blends also help meet increasing engine efficiency standards and lower individual exposure to toxic gasoline aromatics, a blend of benzene and other substances.
Combustion Engines Are Here to Stay but Need Better Fuel
In general, California regulators expect that electric and compressed natural gas (CNG) vehicles will make up an increasing percentage of the vehicles on the road in California by 2020. According to this logic, finding supplies of cleaner liquid fuels (such as ethanol) will be a smaller piece of the LCFS compliance strategy. However, in a February 17 letter from EFC and UAI to CARB, the groups point out that combustion engine technology will likely be dominant on the road for some years to come, writing, “Even in 2040, according to the U.S. Energy Information Administration, cars with gas- and diesel-powered engines will still represent some 95% of the international car market.”
Therefore, the groups argue, increasing the efficiency of traditional combustion engines still remains a top priority to reach a 10 percent reduction in fuel carbon intensity in California. More efficient engines require higher-octane fuels. Automakers, such as Ford, have asked EPA to approve high-octane fuels, noting that they would make it significantly easier for the manufacturers to comply with more stringent miles per gallon (MPG) standards. Ethanol is a cheaper and cleaner version of octane than the current source of octane, aromatic hydrocarbons.
Replacing Gasoline Aromatics with Ethanol Would Provide Substantial Health Benefits
Aromatics are used to provide octane in gasoline, and are comprised of benzene, toluene, ethylbenzene, and xylene (commonly known as the BTEX complex). Despite being known carcinogens, these compounds form approximately 25 to 30 percent of every gallon of gasoline. The burning of these aromatics causes the formation of secondary organic aerosols (SOA). These small particulates carry other toxic emissions, such as poly-cyclic aromatic hydrocarbons (PAHs), through the lungs and into the bloodstream. According to the Harvard Center for Risk Analysis, there is growing evidence that gasoline aromatics are easily converted to SOA in a running engine. EFC and UAI report that, according to the National Emissions Inventory, a majority of aromatic hydrocarbon emissions are from gasoline vehicles.
A growing body of research has linked PAHs to developmental disorders such as autism and ADHD, cardio-pulmonary effects, and various cancers. Indeed, at a recent EPA workshop on these ultra-fine particulates, the link between these small particles and the thickening of arterial walls was discussed. Additionally, research is suggesting these ultra-fine particles have the ability to stimulate the vagus nerve, which feeds directly into the brain and regulates heart function and stress responses.
Domestically Produced Ethanol’s Carbon Footprint is Dropping, Gasoline’s is Growing
According to EFC and UAI, when setting the new LCFS, regulators should consider new life-cycle analyses of ethanol fuels. Scientists at Argonne National Laboratory, a Department of Energy research facility, have devoted 20 years to studying life-cycle emissions of various fuels. According to Argonne's research, energy use for the production of corn-based ethanol has dropped 25 percent since 2008, corn farming energy use has dropped 24 percent, and ethanol yields per bushel have risen three percent. Soil research also finds that soil organic carbon in corn fields has risen due to increased use of no till and conservation tilling practices. According to the most recent GREET model, corn ethanol may already be achieving greenhouse gas (GHG) reductions much higher than the 20 percent reduction mandated by the Renewable Fuel Standard (RFS). Possible GHG reductions for advanced and cellulosic fuels are even higher. In the meantime, the extraction of dirtier crude oils, such as in the Alberta tar sands or the Bakken oil field, means that the carbon footprint of gasoline is actually rising.
In California, corn ethanol is assessed an Indirect Land Use Penalty (ILUC), based on the assumption that the RFS is a driver of land-use change and deforestation globally. The result of this penalty is that domestic cellulosic ethanol and imported Brazilian sugarcane ethanol is favored over domestic corn ethanol. Despite concerns over land-use changes and deforestation, there is little evidence that this is occurring, particularly in the United States. A recent study by Dr. Bruce Babcock, an Iowa State professor and a former California Air Resources Board consultant, supports this finding. The study examines real-world data on land-use change and concludes, “The primary land use change response of the world's farmers from 2004 to 2012 has been to use available land resources more efficiently rather than to expand the amount of land brought into production.”
Newer engine technologies, such as gasoline direct injection (GDI) may increase the number of particles being emitted. As engines advance, so must fuels. Addressing engine design is only half the solution: in order to truly clean up the transportation sector, fuel quality must also be addressed. Domestic renewable fuels should be part of the solution. According to David VanderGriend, President of UAI, “Our research has shown that there is a clear linkage to gasoline and a range of negative health effects. So reducing carbon isn’t just a matter of greenhouse gas and potential climate change but also saving lives by reducing toxic emissions.”
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