Several Class 8 Hybrids Being Developed, But Experts Say Many Obstacles Still Loom

By Eric Miller, Staff Reporter

This story appears in the June 16 print edition of Transport Topics. Click here to subscribe today.

WASHINGTON — Several prototype Class 8 hybrid trucks are currently under development, but the technical and economic obstacles in the way of placing reliable and fuel-efficient heavy hybrid over-the-road trucks in service remain daunting, experts told a House subcommittee.

Rep. Nick Lampson (D-Texas), chairman of the House Subcommittee on Energy and Environment, said trucking is due for a “major technology shift” and the potential for heavy hybrids underscores the need for a “robust” federal program to partner with industry to speed development.

The June 10 hearing was in order to assess the state of medium- and heavy-truck hybrid development as an initial step toward crafting legislation that would encourage the Department of Energy to expand its hybrid technology research, Lampson said.

“Reducing fuel costs and meeting environmental regulations is vital to the bottom line of any company that relies on heavy trucks,” Lampson said. “Given the significant gains to be made in the commercial truck sector and its indispensable role in our economy, we should ensure that federal research and development programs continue to address the need to improve fuel efficiency of heavy-duty vehicles.”

Companies such as FedEx Corp., UPS Inc., Coca-Cola and Pepsi Cola are attempting to improve fuel economy and reduce their carbon footprints by adding more hybrids to their mostly urban fleets, which can spend hours idling in city traffic while making deliveries.

“Despite this potential, there remain relatively few hybrid trucks on the road,” said Terry Penney, a technology manager at National Renewable Energy Laboratory, Golden, Colo.

Trucking, in general, has been slow to adopt the hybrid, Penney said. The reasons he offered for this included high cost, limited commercial production and the need to improve energy storage, power electronics and engine idling systems.

Penney’s conclusion was that developing a reliable and fuel-efficient model for longhaul, heavy trucks is proving to be extremely challenging.

That also was the consensus among panel members testifying before the committee.

The heavy hybrid truck industry is 10 years behind the automobile industry, but is on the “cusp of commercialization,” said Richard Parish, senior program manager of Calstart, Pasadena, Calif., a transportation technologies consortium.

“More than six truck makers and 10 system makers are now developing heavy hybrid prototypes or pre-production products in first applications, but the effort has not yet achieved critical mass and is at an important point in its evolution,” Parish told the committee.

“To break out, these first efforts must succeed and expand. One of the key early barriers to success is that production volumes are low, so prices remain high,” he said.

Cost remains a large obstacle, since hybrid versions of medium- and heavy-duty trucks cost up to 50% more than conventional diesel trucks, Eric Smith, a hybrid engineer with Eaton Corp., Cleveland, told the committee.

Integrating hybrid technology into truck platforms requires different strategies, packaging, system designs and component sizes. In addition, the “market drivers and purchase criteria” are very different in the commercial-vehicle market, when compared with the passenger automobile market, Parish said.

Because longhaul tractor-trailer rigs seldom apply their brakes and travel mostly on the open road, hybrid applications — which typically recoup energy “wasted” when the brakes are applied, storing it to help the main alternator — don’t attain the same fuel savings as medium-duty delivery trucks that operate in an urban environment and brake often. So far, “plug-in” electricity-powered technologies don’t allow trucks to travel long distances.

Smith said the critical technology for hybrid vehicles is the availability of high power output and high energy storage devices. To date, the lithium ion battery is the most promising technology for these vehicles, he said.

“However, these types of batteries significantly increase the complexity and cost of the system,” Smith added.

The good news is that most in the industry believe that as more trucking companies turn to hybrids, costs should go down.

Committee members disagreed on whether the best policy action would be to step up funding for development and testing, impose a carbon tax or offer tax incentives for carriers to purchase hybrid trucks when they are ready for the road.

“The answer is not more taxes, or cap and trade,” said Rep. Randy Neugebauer (R-Texas). “It’s technology.”

“Is the science the problem or the economics?” asked Rep. Bob Inglis (R-S.C.).

The witnesses on the panel were unanimous on both being serious obstacles.

The panelists also agreed that the federal government’s 21st Century Truck Partnership, which conducts research and evaluation through its public-private efforts with the trucking industry, was a step in the right direction, but so far has seemed to lack vision and adequate funding.