A group of DOE National Laboratory representatives have been in Washington this week making presentations to promote the benefits of what they call “Renewable Super Premium” (RSP) fuels. The researchers have found that ethanol fuel blends of between 25 and 40 percent not only enable high octane fuels, but offer real gains (5-10 percent) in vehicle efficiency and significant reductions in greenhouse gas (GHG) emissions.
The presenters are experts that have teamed up to conduct a “scoping study” designed to address barriers to implementing RSP fuels, quantify their benefits and determine if additional research and development is warranted. In a meeting yesterday with the Energy Future Coalition Steering Committee, the researchers from the Argonne and Oak Ridge National Laboratories and the National Renewable Energy Laboratory say that based on findings to date, ethanol is a significant enabler for high octane fuels and RSP fuels can enable improved fuel economy in dedicated vehicles and significant reductions in greenhouse gas emissions.
The discussion of an RSP is appropriate, given the challenges facing the transportation industry and cited by the researchers. A federal Renewable Fuel Standard calls for 36 billion gallons of clean-burning alternative fuels (including more than 20 billion gallons of cellulosic and other second-generation fuels) to be blended into the nation’s transportation fuel supply by 2022. And by 2025, the federally-set Corporate Average Fuel Efficiency (CAFE) standard will be 54.5 miles per gallon fleet-wide. Furthermore, EPA Tier 3 regulations are requiring huge reductions in GHG emissions.
Current octane ratings run from 87 in regular gasoline to 92 in premium. The research team defines RSP fuels as having a research octane number (RON) of about 100 with a 25-40-percent ethanol blend.
The efficiency gains of high-octane midlevel ethanol blends have been demonstrated in research studies at Oak Ridge, as well as at Ford Motor Co. and other testing sites. Those tests show 20 to 40-percent ethanol blends likely offer the optimum benefits of higher octane efficiency, helping offset ethanol’s lower energy density when compared to gasoline.
Environmental analyses by the team are continuing, but they say that while additional GHG reductions depend on the source of the ethanol, cellulosic ethanol in an E40 blend could produce an additional reduction in emissions of about 30 percent.
Addressing the question of whether retail infrastructure is a “showstopper” ” to RSP fuels, the research team, which says about 20 percent of stations have to carry new fuel for it to be considered “widely available,” determined costs to upgrade stations for blends of E25 and higher, and identified compatible equipment by manufacturer and model. The found that technically E25 and higher blends are possible, though marketwise, E25 is less costly and more acceptable to retailers, given that most materials used are compatible. The team concedes that an issue of stations not being required to keep equipment records presents a challenge for determining compatibility. But the scientists insist that the infrastructure barrier as suggested by some is overstated.
The team notes that feedstock availability and cost do not limit deployment of RSP fuels, but in most scenarios studied, vehicle market penetration sets a ceiling for total potential ethanol usage. Under an E40 rapid deployment scenario, actual ethanol usage is also limited by biorefinery construction. Nonetheless, the researchers cite preliminary results that show potential ethanol consumption in 2035 ranging from 28 to 58 billion gallons per year for the E40 rapid deployment scenario, while consumption would range from 18 to 32 billion gallons per year under a scenario driven by the price for implementing E25 fuels.
Provisional findings to date are encouraging. In addition to higher efficiency and significant reductions in GHG emissions, pursuit of RSP fuels would result in little decrease in overall U.S. refinery efficiency, even at very high demands, while giving refineries additional opportunities to export gasoline products. RSP fuel would be immediately usable in the 17-18 million flex-fuel vehicles (FFVs) currently on the road.
Despite what the petroleum monopoly would want us to believe, this still evolving success story from our national laboratories shows that biofuels can provide the means necessary to improve the performance of our nation’s fleet of cars and light trucks by making them more efficient and cleaner burning. Federal regulators should recognize the benefits that higher-level biofuel blends can offer in meeting administration climate change goals and adopt meaningful policies that can allow these clean home-grown fuels to help meet our energy challenges.