High compression engines make more power with fewer carbon emissions. But they also can suffer from pre-ignition or knocking that causes internal engine damage unless they burn fuel that is up to the task. One way to make higher compression ratios possible is by increasing the octane rating of the fuel we feed our infernal combustion engines. One way to do that is to increase the amount of ethanol that gets blended into the gasoline we use here in the United States.
Dan Nicholson, vice president of global propulsion systems for General Motors, tells Automotive News he could boost fuel economy in most engines by about 5 percent if America had the same higher octane gasoline as Europe. Gasoline on the Continent is 5 to 6 octane points higher than it is in the US.
Speaking to a conference of automotive industry executives and engineers recently, Chris Grundler, director of the EPA’s office of transportation and air quality, said his agency realizes that fuels have a role to play in enabling automakers to meet tougher fuel economy and emissions regulations. The EPA has been collecting relevant data about ethanol for a number of years.
“After 2025, we should talk about what the future fuels should look like and what is the optimum mix of vehicle and fuel technologies. It is not as simple as the automakers might think it is under the law, and we have to follow the law. We have had requests to regulate octane for many years.“ There are some provisos,” he added. “For us to intervene and set fuel standards, we need to show that there is an air quality benefit or that, absent regulations, that it is somehow inhibiting the after-treatment or other parts of the vehicle. And that the benefits outweigh the costs.”
“[Octane] will have to be part of the conversation,” said Mike McCarthy, CARB’s chief technology officer at the conference. “I think it has to be on the table.”
Blending more ethanol into gasoline is not a straight forward proposition, however. Yes, ethanol makes more power. That’s why Indy Car race engines burn a mix frequently known as E85 that is 85% ethanol and only 15% gasoline. But ethanol also lowers gas mileage. The tradeoffs may make the cure worse than the disease. One consideration is the source of the ethanol. Higher compression ratios may make more powerful engines, but they also lead to higher NOx emissions. That’s the nasty stuff that got Volkswagen in so much trouble with its diesel engines. It would be irresponsible to lower carbon emissions by raisning NOx emissions, wouldn’t it?
In the US, much of our ethanol comes from corn. It doesn’t take a rocket scientist to figure out that if corn is being used to make fuel, it can’t be used to feed people or animals. That means the price of food goes up for everybody. Agribusiness loves the current mandate that all gasoline contain at least 10% ethanol and would like to see the percentage increased. It likes that the government requires everyone to buy its products. Talk about your socialism! But ethanol can be made from almost any plants, including those normally considered trash weeds, like switch grass.
It can also be made from hemp, but in America we have this insane idea that hemp and marijuana are the same thing. (They are genetically related.) It’s as if people believe just standing downwind of a field of hemp would cause people to go into a psychedelic trance like the hordes of humanity at Woodstock. The entire nation could soon start to resemble the audience at a Grateful Dead concert. It really is time for America to grow up.
There are many stakeholders in the ethanol sweepstakes. Some corporations stand to make enormous profits if the federal government mandates a higher percentage of ethanol in our nation’s gasoline. But no matter what happens, the EPA’s Grundler says no action is likely on ethanol until after 2025, when the next round of fuel economy/emissions regulations are scheduled to take effect.
For the moment, car makers are reluctant to make engines that need higher octane premium gas, which averages 50 cents or more higher than regular gas at the pump. Americans are lovin’ on their low gas prices. Woe betide anyone who messes with our God given right to cheap gasoline!