Auto companies must pursue a long list of incremental technological improvements to meet the U.S. government’s new Corporate Average Fuel Economy requirements by 2025, industry leaders said recently at a Pew Clean Energy Program panel discussion in Dearborn, Mich.

But the experts said electric vehicles won’t play a big role in the helping the industry meet the standards.

Against a historical backdrop of the Automotive Hall of Fame, industry leaders said the future of the vehicle is predicated on advancements in many different areas, such as lightweighting and engine efficiency.

The U.S. government is requiring the industry to hit average fuel economy of 54.5 miles per gallon by 2025, although various credits and loopholes have created some exceptions.

Jay Baron, president of the Ann Arbor, Mich.-based Center for Automotive Research, which recently formed the Coalition for Automotive Lightweighting Materials, said vehicles are primed to get an influx of new materials.

Baron said the biggest opportunity to reduce weight is in the vehicle body. One example of an automaker that’s considering weight-reduction actions is Ford, which may integrate more aluminum into the F-150 Series pickup truck.

“The car is not going to be aluminum-intensive, steel-intensive or composite-intensive. It will have all these materials in it,” Baron said.

Baron predicted that plug-in hybrid electric vehicles won’t be advanced enough to play a key role in helping the industry meet the 2025 Corporate Average Fuel Economy, or CAFE, standards.

“But I certainly think hybrids” will be important, he said.

United Auto Workers international representative Brad Markell agreed: “Electrification is not super-important to meeting this standard,” he said.

Andrew Smart, director of industrial relations and business development and director of the Society of Automotive Engineers International’s automotive headquarters, said basic engine efficiency is a key opportunity for fuel economy improvements. He said only about 20 percent of the “energy in fuel goes into driving the wheels.”

Smart said there are many different opportunities for small but meaningful advancements, including reducing friction in bearings, reducing the number of piston rings in an internal combustion engine, and improving variable valve performance.

“The devil is in the details,” he said. “That’s where the mechanical engineers are really working very hard at the moment.”

Doug Baker, CEO of TECAT Engineering, said the industry will “have to leverage today’s technologies in the best way we can” to reach CAFE standards. But he cautioned that some technologies won’t help much. For example, he said direct fuel injection is “starting to reach a limit.”

Phyllis Cuttino, director of clean energy program of the Pew Environment Group, said fuel economy standards can create jobs for the U.S.

“We have got to be at the forefront of capturing that economic opportunity, manufacturing the very kind of technologies that we innovate here in the United States and exporting them throughout the world,” Cuttino said.

Markell said corporations are maneuvering to capitalize on the CAFE standards.

“There’s a lot of opportunity for companies to look forward and see what the components are going to be,” he said.

Baron said one industry set to take advantage of the new CAFE standards is the materials and composites manufacturing sector. He said adhesives would be “an enabler” in allowing manufacturers to integrate lighter materials into the vehicle.

But composite-material makers are still learning about the auto industry, he said.

“Quite frankly, the auto industry is a little bit of an enigma to them,” he said. “This is all new, foreign language to the chemical guys. For them to break into the auto industry, they have an uphill battle.”