Sometimes it helps to state the obvious: If you want to reduce emissions from vehicles, you should consider both the vehicle and the fuel it uses.
A rule proposed recently by the Environmental Protection Agency (EPA) to reduce greenhouse gas emissions from vehicles — now the single biggest source of U.S. global warming pollution — was a solid effort on the first point (the vehicle itself) but a complete whiff on the second. Ignoring entreaties from the auto industry and others, EPA did not include a fuel quality improvement pathway in their proposed rule.
The Department of Energy, on the other hand, clearly understands the need for a coordinated approach. Since 2016, researchers at nine National Laboratories participating in the Co-Optimization of Fuels & Engines initiative (known as Co-Optima) have explored how simultaneous innovations in fuels and engines can boost fuel economy and vehicle performance, while reducing emissions.
Stating the obvious, the Co-Optima team says it “views fuels not as standalone elements in the transportation system, but as dynamic design variables that can work with modern engines to optimize and revolutionize the entire on-road fleet.”
This matters in three ways: in the amount of emissions reduced, the time to achieve those gains and the implications for public health. Enabling greater use of biofuels like ethanol would produce better results in all three categories — or, to put it another way, would more than double the benefits of the new regulation.
The reason is octane. Higher-octane fuels enable better performance and efficiency. If all the gasoline on the road had the octane of premium, or higher, automakers could tweak new car engines to take advantage — increasing fuel economy, improving performance and reducing emissions.
Ethanol is a powerful octane additive, and almost all gasoline today already contains 10 percent ethanol. Increasing that amount to 25 percent or 30 percent would reduce greenhouse gas emissions from light-duty vehicles by more than the proposed EPA rule — and just as important, it would do it faster. The reason is simple: Such fuels could be widely deployed today and used by the cars already on the road. The EPA rule applies only to new cars.
The White House has set a goal of cutting U.S. greenhouse gas emissions in half by 2030 — a tall order, but one that is critically needed to avoid the buildup of these gases in the atmosphere. How fast emissions go down is just as important as how much.
Increasing biofuel blends would also enable reductions in a toxic soup of octane additives called aromatics. These carcinogenic compounds, which amount to approximately 20 percent of every gallon of gasoline, has cascading effects on public health, most alarmingly on young children — especially in high-traffic urban areas that suffer the disproportionate harms called out by advocates for environmental justice.
A recent General Motors study found that nearly 96 percent of the fine-particle emissions from gasoline are caused by the aromatics in the fuel. Fine particle pollution from fossil fuels is the leading cause of premature death in the world, responsible for cardiovascular, respiratory, and other health effects that kill more than 8 million people annually.
Once inhaled, the smallest particles reach the deepest part of the lungs and enter the bloodstream, even the placental barrier and reach the brain. Fetal exposure to extremely low levels of emissions from aromatics has been associated with developmental delay at age 3 and reduced IQ at age 5, similar to the effects reported for children with elevated levels of lead in their blood.
Nor is engine technology going to solve the problem. Most vehicles entering the market today use a technology called gasoline direct injection to enhance fuel economy performance. Unfortunately, it also greatly increases the emission of ultrafine particles from gasoline.
It doesn’t have to be this way. For air toxics from vehicles, the Clean Air Act requires “the greatest degree of emission reduction achievable through the application of technology which will be available.” As the Department of Energy has shown, vehicles and fuels should be seen as parts of an integrated system.
EPA whiffed on this issue in its recently proposed rule. But in finalizing the rule, it could signal its intent to fully consider the rule of fuels in reducing greenhouse gas emissions and protecting public health in its next rulemaking in this area — as soon as next year. EPA cannot continue to close its eyes to half the problem — and the solution.
Ernest C. Shea is president of Solutions from the Land, a not-for-profit organization that brings agricultural thought leaders to the forefront of conversations about the food system, the environment and the future. Follow Solutions from the Land on Twitter: @SfLDialogue