In addition to developing hybrids and other forms of electrified drivetrains, automakers are turning to downsized turbocharged engines with direct injection to improve fuel economy. Many of those engines already require high-octane fuel. Octane is measure of a fuel's resistance to self-ignite, so higher octane numbers allow for even higher engine compression without risk of knock. General Motors' Dan Nicholson says higher octane can boost fuel economy by as much as five percent. And in Europe, octane levels are about five percent higher than US fuel levels.
As for the higher prices associated with premium gas and higher-octane fuels, the gap from regular gas may narrow because hi-test would be produced in higher volumes and therefore lower the production cost. Premium gasoline averages $2.70 a gallon, or 47 cents a gallon more than regular gas, according to the US Energy Information Administration as of this story's publication.
An EPA spokesperson confirmed to Autoblog that the EPA's Grundler recently used a panel discussion at an automotive-industry conference to talk about the various ways the transportation sector can reduce greenhouse-gas emissions. Additionally, some automakers already certify some vehicles for higher-octane gasoline for the purpose of CO2 reduction. But the spokesperson added that the possibility of higher octane being used as a method of cutting emissions "remains an open question."