Shifting up to higher octane
If the majority of light-duty vehicles in the United States ran on higher-octane gasoline, the automotive industry as a whole would reduce its carbon dioxide emissions by 35 million tons per year, saving up to $6 billion in fuel costs, according to a new analysis by MIT researchers. In a study published in the journal Environmental Science & Technology, the team considered a scenario in which fuel is manufactured under a redefined octane rating — the measure of a gasoline’s ability to resist engine knocking during combustion. Currently in the United States, a car’s octane rating is based on the antiknock index (AKI) — a specification for fuel composition that is determined by a standard research octane number (RON) and a motor octane number (MON). The resulting octane ratings for today’s car engines typically range from 87 (regular fuel) to 93 (premium, or high-octane, fuel) — numbers that are commonly displayed at...