Message to the U.S. government: Engineers need adequate time to develop the technology solutions for meeting 2017-and-beyond fuel-economy rules, which are expected to be ultra-stringent.
That notice was sent by several veteran industry engineers at the SAE 2011 World Congress during the April 12 “Powertrain Strategies for 2017 and Beyond” panel discussion. It was subtly addressed to fellow panel mate Margo Oge, Director of the U.S. EPA’s Office of Transportation and Air Quality.
Oge, in her third appearance at an SAE Congress, kicked off the panel by outlining the Technology Assessment Report (TAR) now under way by EPA, NHTSA, and the California Air Resources Board. Authors of the TAR are evaluating, on a company-by-company basis, the industry’s capability to develop a fleet fuel-efficiency average for light vehicles of over 60 mpg—a 6% per year improvement—by 2025.
The report will be used to create the government’s proposal for 2017-2025 vehicle fuel-efficiency standards. The proposal is due in September; final rules are expected in July 2012. Oge called the TAR “the most robust technology analysis EPA has ever done.” She provided few details other than saying the regulators intend to build in “flexibilities” including a mid-program review.
“We want to avoid an unintended consequence” such as forcing vehicles with a specific technology on consumers, she noted. Oge admitted the cost of batteries is “keeping me awake at night,” along with the challenge of vehicle mass reduction (without affecting occupant safety).
Oge also had to defend her agency during the Q&A hour. When asked by an audience member if EPA would survive some recent Congressional calls to eliminate the agency, she asserted, “EPA is here to stay.”
Following Oge’s presentation, AVL Chief Technologist Paul Whittaker noted that vehicle mass “creep” will make meeting any proposed 2017 standards “very challenging.” He ran down a list of propulsion technologies in the industry’s pipeline. “Clean” diesel in its current configuration “is not clean enough” to meet U.S. Tier 3 emissions standards, Whittaker said. And hydrogen fuel cells are not yet able to meet 100,000-mi (161,000-km) durability requirements.
Gasoline engines will continue to improve and offer a viable solution when combined with hybrid-electric drives. But they must maintain their cost advantage over diesel.
Lee Carducci, President of Revstone Power-Tec, a racing technology specialist, presented an informative look at how precision machining of cylinders, tighter ring-to-bore tolerances, and lightweight metal alloys will be needed for automakers to accommodate increased cylinder pressures, compression ratios, and thermal loads in future engines. “We’re also going to go to stronger gaskets and seals,” he said.
“Without biofuels, the 450-ppm CO2 glide path [for 2017 and beyond] becomes very, very difficult,” said Bob Fascetti, Ford’s Director of Global Engine Engineering. He stressed the need for a single Research Octane Number (RON) fuel in the U.S., which would allow increased compression ratios without the risk of knock.
Electrification will grow, Fascetti noted, but the rate of growth will depend on the rate of decline in battery costs.
A key trend noted by Uwe Grebe, General Motors’ Executive Director of Global Powertrain Advanced Engineering, is the synergy of powertrain and vehicle engineering. “It needs to happen as a team,” Grebe asserted, so that vehicle efficiency (and particularly mass reduction) can be optimized holistically.
“Few powertrain technologies are universally applicable,” he noted. “Different technologies will apply to different vehicle portfolios and different duty cycles.”
Honda R&D Senior Chief Engineer Takashi Moriya described his company’s technology path toward greater vehicle efficiency. The path includes significant efforts in hydrogen fuel cell vehicles, controlled auto ignition combustion strategies, and plug-in hybrids.
“The new technologies need long lead times to be truly accepted in the market,” he said, echoing similar statements by fellow panelists.