February 4, 2016
By Holly Jessen
Which needs to come first, a new high-octane midlevel ethanol blend or new vehicles optimized to more efficiently take advantage of the higher octane content?
“It is that classic chicken and egg thing,” says Timothy Theiss, bioenergy technologies program manager at Oak Ridge National Laboratory. “The analysts say it's the simultaneous introduction of a new fuel and a new vehicle, which is very difficult.”
Brian West, deputy director of the Fuels, Engines and Emissions Research Center at ORNL, offered a slight tweak to that perspective. “All we are talking about doing, and I don't mean to make it sound easy, is just changing that ratio a little bit,” he says, adding that the nation already has a gasoline and ethanol infrastructure. “It would certainly seem to me to be a much simpler thing than putting in a whole new infrastructure of, say, hydrogen.”
West believes a new E25 or E40 blend, perhaps marketed as a “renewable super premium,” could be sold in a way that is a win for consumers, retailers and everybody involved. In fact, vehicles optimized for the new fuel could be manufactured today. “I often say, there's not a good technical reason we couldn't see this in the marketplace in five or 10 years,” West adds. “That doesn't mean I think it will happen in that time frame. There's just too many parties that need to be in agreement.”
Thiess and West are two of many researchers at ORNL, Argonne National Laboratory and the National Renewable Energy Laboratory who have been engaged in a study since 2013. The goal of the U.S. DOE-sponsored scoping study was to assess the potential of an E25 to E40 mid-level blend.
In mid-January researchers were wrapping things up, preparing to provide a short, high-level summary to the DOE. The last of the data will be released in publications within the next year, West says. Up next is the Optima initiative, which will focus on developing new, co-optimized fuels and engines to maximize performance and carbon efficiency. While the high-octane fuel study focused specifically on ethanol, Optima will look at fuels like ethanol as well as other high-octane fuels, Thiess says.
Significant Findings
The high-octane fuel study found that E25 and E40—when used to fuel a vehicle optimized for the blend—could achieve volumetric fuel-economy parity with E10. In other words, each additional gallon of ethanol added would displace a full gallon of gasoline and fuel economy would be the same as one of today's vehicles using E10. Vehicle efficiency would also increase, at 5 percent for E25 and 10 percent for E40.
Of course, fuel economy varies according to multiple factors, such as how fast the vehicle is driven and engine design. “Not everybody is going to see all of this across the board every time,” Theiss says. “Your mileage may vary.”
An ANL report concluded that, compared to E10, when 40 percent corn ethanol was used for blending, total greenhouse gas emissions were reduced by 18 percent. If corn stover were the feedstock, E40 achieved a 32 percent GHG emission reduction.
NREL was involved in the high-octane fuel study in several capacities, says Robert McCormick, principal engineer and platform lead in fuels performance R&D. For example, a market analysis concluded that high-octane vehicles could make up 43 to 79 percent of light-duty vehicle stock by 2035. Another thing NREL completed was an infrastructure assessment. “There are no technical issues in deploying equipment for higher ethanol blends, only cost considerations and station knowledge of their equipment,” he says.
That's what's exciting to Thiess about the high-octane fuel study. “In this, we're finding we have a lot of ands,” he says. “We can get better fuel economy. And. When ethanol is traditionally priced a little less than gasoline, we can get a fuel that is a little bit less because we are using less petroleum and more ethanol. And. We're showing that we'd get pretty nice greenhouse gas emission reductions. And. We're showing that the vehicle manufacturers would be favorably inclined to build those vehicles. And. We're showing that the biofuel infrastructure could pretty much be adapted to handle it. And. We're showing that there's a lot of feedstock out there that could be used to make it. So, there's a lot of ands, and not the major ors, where we have to make very big trade-off decisions right up front. Now, that's not to say that it's not a difficult thing. It is very difficult to introduce any new fuel. And this would be no exception. But there are a lot of benefits that stack on top of each other.”
Making It Happen
In order to make high-octane fuels and vehicles a reality, quite a few players, including the U.S. EPA and the auto industry, have to get on board. “For manufacturers to build cars that are dedicated for this fuel, I think a number of things have to happen,” West says. “It has to be widely available. They have to believe the consumer is going to buy it all the time, or they aren't going to get the fuel economy benefit that they are getting in the certification test. In order for the consumer to buy it all the time, it has to be on a cost-parity basis with E10.”
But that doesn't mean that the fuel can't be sold until that happens. In fact, E30 is already being sold at some blender pumps across the nation and work to increase the infrastructure for higher ethanol blends is ongoing. And, most flex-fuel vehicles on the road today can already use midlevel ethanol blends and actually see a performance benefit doing so. Thiess sees the FFV fleet as a bridge across the chicken and egg dilemma in establishing a new midlevel ethanol blend and new vehicles optimized for that fuel.
Read the original story: E25, E40 for the Masses