The auto industry has signed on to proposed federal mandates to dramatically improve vehicle fuel economy. But for automakers to meet new standards, some technologies will have to be invented.
"The auto industry has agreed to meet targets that we don't know how we're going to meet," says Tom Baloga, vice president of engineering at BMW of North America. "We're ready to make commitments to tough goals. What we need is time and we need certainty."
The Obama administration, the EPA and the National Highway Traffic Safety Administration have widespread industry support for requiring nominal fleet averages of 54.5 mpg in 2026. (Because of various exceptions and credits, the real-world average likely will be in the low 40s.) Current rules require a 2012 model year industry average of 29.7 mpg.
"To reach those numbers, there is technology that is going to have to be invented," Baloga says.
Already used extensively are turbochargers, multispeed transmissions and aerodynamic improvements. But new technologies are in the works, and automakers are betting on a few that seem plausible.
-- Integrated road memory: Imagine an onboard navigation system that remembers and recognizes a driver's daily route to work -- not merely the left and right turns, but the uphills and downhills. If integrated with the vehicle's engine controls, the system could plan power use more efficiently.
Knowing that a steep hill is a half mile ahead, the engine would reserve power before reaching it. The coolant pump would know to work harder to cool the engine before reaching a highway entrance ramp. An upcoming downhill stretch would be a scheduled moment to recharge the battery.
Navigation systems companies such as TomTom International are developing the technology to make that possible. BMW and others are watching.
"If you can anticipate the route of the vehicle, you could anticipate and manage the engine of the vehicle to maximize performance," Baloga says. "It could adjust the charging logic of the battery. It can allow the voltage to drop to a certain level, knowing that it will be coasting down a hill in 500 yards and you'll be stepping on the brake and generating energy to recharge. This is an area of development we're looking at. "
-- Low rolling-resistance tires: Automakers are using tires that reduce rolling resistance, but how far can they take the concept?
A new tire from Goodyear adds 2.5 mpg to the highway fuel economy that will be posted by the 2013 Chevrolet Malibu, says Daryl Wilson, lead engineer on the car's eAssist powertrain system.
The 2013 Nissan Altima, arriving this month in showrooms, uses low rolling-resistance tires from Continental, Dunlop and Bridgestone. Last year, Bridgestone declared a goal of increasing the rolling efficiency of its tires 25 percent by 2020. Its Ecopia tire shows the path: Proprietary compounds help reduce resistance generated by the tire's heat, and new materials make the sidewalls sturdier to make road contact more precise.
-- Lighter windshields: Plastic or thinner glass would trim several pounds, but there are problems with both.
Plastic, standard in the motorcycle industry, is more expensive than glass for vehicle windows and tends to make the vehicle interior hotter. Thinner glass can lead to noisier cabins, says Jim Shepherd, who was just named president of Carlex Glass.
In recent years, glass suppliers such as Carlex have looked at changing the thickness of all windows to reduce total weight, he says. Heavier side windows can reduce the cabin noise that results from thinner back glass, Shepherd says, and the windshield can be made thinner by improving the acoustic vinyl between the windshield's two glass layers.
-- Heat capture: Harnessing heat emitted by vehicles could slash fuel use. Last year, Ford and General Motors began experimenting separately with thermoelectric technology, which channels engine heat through semiconductors that convert it to energy. Ford's program uses thermoelectric technology developed by Amerigon Inc., while GM is developing the technology internally.
A different technology, thermophotovoltaics, is under development at MTPV Corp., an Austin, Texas, technology supplier. The technology uses semiconductors and other devices to capture heat and convert it to alternating current to run vehicle electronics and cooling, potentially replacing vehicle alternators, says Vice Chairman Dave Mather.
-- Stop-start technology: Systems that pause combustion while vehicles are stopped in traffic have been on the market since the 1980s. But they have been slow to take hold in the United States, except on hybrids and electrics.
That is changing. Stop-start suppliers such as Robert Bosch, Valeo and Denso are increasing penetration on vehicles sold in the United States. The 2012 BMW 3 series and the 2012 Mercedes-Benz C class offer stop-start. The game changer may come this summer when the technology appears on the mainstream 2013 Ford Fusion. Ford intends to use the technology on other vehicles.