CARB Would Mandate Refiners to Offset Ethanol-Related Emissions

By Published On: March 30, 2007

The California Air Resources Board proposed standards that would require oil companies to retool their refineries by 2012 to produce less polluting ethanol-gasoline blends. While refiners carry out the work between 2010 and 2012, they would have to offset the extra emissions caused by the biofuel by such means as paying people to scrap old cars or lawn mowers that have high emissions. The air board outlined the offset plan in proposed amendments to its “predictive” model. That model sets air pollution emissions parameters for gasoline sold in California but allows refiners to devise different chemical blends to meet the standards. The air board staff plans to bring the amendments to its board for possible adoption on June 14, said Steve Brisby, CARB fuels section manager, at a public workshop on the proposal March 23. The changes are needed to reverse increases in both volatile organic compounds and nitrogen oxide emissions caused by blending low levels of ethanol into gasoline. Both contribute to unhealthful levels of ozone, a respiratory irritant that blankets much of the state during the warm months. Nitrogen oxides also form fine particulates in the air (Circuit, March 2, 2007). Gasoline sold in California today contains 6 percent ethanol. The level is expected to rise to 10 percent in response to the federal Energy Policy Act of 2005, which mandates increased use of the biofuel in gasoline, and California’s developing low-carbon fuel standard (Circuit, Feb. 2, 2007). Among the key proposed changes is a requirement that refiners reduce the sulfur content of gasoline to cut the nitrogen oxide emissions caused by adding ethanol. The change is backed by automakers because low-sulfur fuel works better in lean-burn engines. The air board’s Brisby noted that samples of gasoline sold at hundreds of service stations in California show that refiners already largely meet the proposed 20-parts-per-million sulfur standard. However, refiners oppose the change. “You’re overestimating your reduction of nitrogen oxides by controlling sulfur,” said Albie Hochhauser, Western States Petroleum Association representative. “You’re restricting the ability to use some high-sulfur crudes or blends you may want to use to produce the gasoline the public needs.” In the future, he said, low-sulfur crude is likely to become more difficult to find. Instead, refiners expect sulfur levels to increase in both crude oil itself and refined blend stocks imported to make gasoline. Meeting the air board’s proposed standard will require refiners to invest “hundreds of millions of dollars” in sulfur-removal equipment at their plants, said Hochhauser. That cost will be passed on to motorists. Air board staff agreed to meet with refiners to discuss how the proposed standards might affect refiners’ ability to produce enough fuel for state motorists before issuing a staff report on the plan in mid-April.

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