Economic and Environmental Benefits of Higher-Octane Gasoline

We quantify the economic and environmental benefits of designing U.S. light-duty vehicles (LDVs) to attain higher fuel economy by utilizing higher octane (98 RON) gasoline. We use engine simulations, a review of experimental data, and drive cycle simulations to estimate the reduction in fuel consumption associated with using higher-RON gasoline in individual vehicles. Lifecycle CO2 emissions and economic impacts for the U.S. LDV fleet are estimated based on a linear-programming refinery model, a historically calibrated fleet model, and a well-to-wheels emissions analysis. We find that greater use of high-RON gasoline in appropriately tuned vehicles could reduce annual gasoline consumption in the U.S. by 3.0–4.4%. Accounting for the increase in refinery emissions from production of additional high-RON gasoline, net CO2 emissions are reduced by 19–35 Mt/y in 2040 (2.5–4.7% of total direct LDV CO2 emissions). For the strategies studied, the annual direct economic benefit is estimated to be $0.4–6.4 billion in 2040, and the annual net societal benefit including the social cost of carbon is estimated to be $1.7–8.8 billion in 2040. Adoption of a RON standard in the U.S. in place of the current antiknock index (AKI) may enable refineries to produce larger quantities of high-RON gasoline.