GM, Honda execs agree: Higher octane gas needed to optimize ICE efficiency

  • 03-Aug-2016 07:11 EDT
article_14940-b.jpg

Robert Bienenfeld of Honda (left) and GM's Dan Nicholson are on the same page regarding the engine-efficiency benefits of higher octane fuel. (Lindsay Brooke photos)

Raising the octane level of pump gasoline in the U.S. is integral to optimizing advanced combustion engines now in development, said GM and Honda executives at the 2016 CAR Management Briefing Seminars in Traverse City, MI. Their comments prompted positive but non-committal comments from Chris Grundler, Director of the Office of Transportation and Air Quality for the U.S. EPA.

During a panel discussion on future powertrains, Dan Nicholson, VP of Global Propulsion Systems at GM, and Robert Bienenfeld, Assistant VP of Environment and Energy Strategy at American Honda, agreed that the industry must push for a higher fuel-octane “floor” in the U.S.

“Higher octane fuels are the cheapest CO2 reduction on a well-to-wheels analysis,” Nicholson told panel moderator Brett Smith of CAR. “Fuels and engines must be designed as a total system. It makes absolutely no sense to have fuel out of the mix” of engine-technology discussions, he asserted.

Nicholson added that higher-octane, purpose-designed fuels “can be delivered very cost effectively.” A U.S. Dept. of Energy analysis proved the benefit of higher octane levels in improving combustion efficiency and reducing engine-out CO2, he said.

Honda’s Bienenfeld pointed out the benefits of higher fuel octane levels on advanced turbocharged engines operating under high-load conditions and in large-vehicle applications. He noted that boosted gas engines, hybrids and fuel-cell vehicles are on the future-development path at Honda. Nicholson touted the trend toward higher Otto cycle  compression ratios and said his engineering teams are looking at Miller cycle combustion, in conjunction with turbocharging, “earning its way into the portfolio.”

Nicholson also said he’s bullish on diesels in the U.S., “which is one of the few growth markets” for compression-ignition engines, he stated.

Regarding 48-volt hybrids, Honda considers them to be cost effective “if the [current] standards stop at 2025,” Bienenfeld said.

EPA’s Grundler, speaking at MBS later in the day, noted that his agency is participating in the U.S. Dept. of Energy’s Optima project studying future fuels and has a working group focused on gasoline octane. “Fuel changes are not part of the TAR [Technology Assessment Report, part of the Mid-term Review of the current CAFE regulations],” he said, while suggesting that higher octane levels be considered for after 2025 “as long as increasing octane levels do not increase greenhouse-gas emissions.”

The Optima project aims at developing co-optimized fuels with a range of new engines for light-, medium-, and heavy vehicle use. Announced at the SAE High-Efficiency Engines Symposium by Dr. Wagner, Director of the Fuels, Engines, and Emissions Research Center at Oak Ridge National Laboratory, Optima is targeting a 30% reduction in petroleum consumption, per vehicle, compared with a projected 2030 base case that uses today’s fuels. The initiative is a collaboration with producers of gasoline and ethanol and the auto industry.

If Optima achieves its goal, it could reduce petroleum consumption by 4.5 billion barrels and save consumers up to $50 billion, according to the DoE.

Raising the U.S. octane “floor” will be essential for new combustion strategies currently in development for the 2020s including advanced Miller cycle and those combining lean-burn and stoichiometric operation aimed at achieving peak efficiency levels of 50%. and above. ORNL’s Dr. Wagner told the SAE audience that some multi-cylinder dyno engines have pushed beyond 55%.

Mazda’s Skyactiv program is progressing through G1, G2, and G3 development stages toward a marriage of Otto and Diesel cycle characteristics. Engineers’ target for the G3 is 18:1 compression ratio at lambda 2.5—a 40% improvement in thermal efficiency by setting the ideal pressure and temperature for homogeneous charge compression ignition (HCCI).

In Europe, the 102-RON (research octane number) “super premium” gasoline that’s widely available helps deliver a 10% increase in fuel efficiency for engines running compression ratios above 11.5:1, compared with engines running 9.0 to 9.5:1 using the 95-RON fuel that’s marketed as the mid-grade gas in Europe.

Share
HTML for Linking to Page
Page URL
Grade
Rate It
4.25 Avg. Rating

Read More Articles On

2016-06-28
Start of production for the plug-in hybrid Chrysler Pacifica minivan begins in late 2016, marking a milestone as Fiat Chrysler Automobiles (FCA)'s first mass-produced PHEV.
2016-07-10
Chinese planners are focusing on NEVs to become a mainstay of its future automotive production and consumption. Although there’s overcapacity throughout China’s automotive supply chain as the economy slows down, a number of new companies are expected to enter the NEV market.
2016-06-28
More hydrogen fueling stations in California and additional electric vehicle charging stations across the U.S. could reduce the range anxiety consumers have about driving these advanced-technology vehicles.
2016-07-26
As President and CEO of the Center for Automotive Research (CAR) in Ann Arbor, Dr. Baron and his research teams are engaged with technology issues across a broad front, but even a brief conversation with him reveals his deep passion for plants, advanced processes and materials. Get him talking about Lightweighting and he won’t stop.

Related Items

Technical Paper / Journal Article
2003-10-27
Technical Paper / Journal Article
2003-10-27
Training / Education
2011-04-09
Training / Education
2009-12-15