The Obama administration on Friday is expected to unveil a long-delayed plan to slash smog-forming sulfur emissions from gasoline, despite objections from the oil industry.
Public health advocates say the mandate for low-sulfur fuel would provide a big boost in air quality, quickly reducing ozone pollution from vehicles and the respiratory illnesses that go along with it.
Under the so-called Tier 3 fuel standards refiners would have to cut sulfur emissions from gasoline to 10 parts per million, down from a current threshold of 30 parts per million.
The Environmental Protection Agency said earlier this year it was on track to propose the standards in March and finalize them by December. Sources familiar with the rule confirmed it was set to be released Friday.
Automakers say the change would allow them to build cleaner combustion engines, providing new avenues to meet environmental mandates. Lower sulfur fuel allows catalytic convertors to work more efficiently, causing fewer tailpipe emissions.
But refiners have been lobbying the Obama administration to soften or withdraw the proposal, warning that the change would require expensive changes at their facilities, including installation of energy-intensive hydrotreaters to strip more sulfur out of gasoline, without proven health benefits. Industry representatives note that they’ve already cleaned up sulfur emissions considerably, down from a previous threshold of 300 parts per million.
The remaining sulfur is especially difficult to remove from gasoline, said the American Petroleum Institute’s Bob Greco. To strip out the sulfur, refiners say they would have to install energy-hogging hydrotreaters that could actually boost the carbon footprints of those facilities, even as regulators are on a separate path to set limits on greenhouse gas emissions from those plants.
Refiners also insist the extra cost could mean motorists pay more for the lower-sulfur gasoline. Estimates range from an industry-backed study’s projection of an extra 9 cents per gallon to the EPA’s prediction of just one penny more per gallon.
The current standards are designed so refiners must meet an annual average of 30 parts per million — with an absolute cap of 80 parts per million. An open question is whether the EPA will seek to lower the ceiling on sulfur emissions in addition to the overall average.