Mild-Hybrid Technology Draws Attention

Continental Teves Inc. may position itself as a “safety supplier,” but fuel-sipping technology is slated to take up more of the company's time as its mild-hybrid (low-voltage stop-start assist) customer list is poised to grow.

“Fuel efficiency will be an issue we will address more and more in the future,” Peter Reith, vice president-advanced engineering for Continental, tells Ward's.

The company's integrated starter alternator (ISAD) is at the heart of its expanding strategy, Reith says. General Motors Corp. uses the system for its mild-hybrid pickups, which currently are confined to commercial fleets, and Chrysler Group will employ the technology in mild-hybrid Ram pickups meant for fleet distribution later this year.

The supplier says it is readying ISAD for two European OEMs that plan to use the technology in volume production. ISAD is designed to work with regenerative braking to provide a 15% fuel economy gain.

GM has opted for Robert Bosch GmbH's regenerative braking system in favor of Continental's. However, Continental supplies Ford Motor Co. with its system for the Escape Hybrid, and Reith estimates the device captures 15%-20% of potentially lost energy and returns it to the battery system.

Ford has not announced plans to implement ISAD and, instead, seems intent on focusing on full hybrids. Continental sees GM's mild-hybrid strategy as a way for OEMs to meet rising fuel economy standards in the U.S. and Europe without having to invest as heavily as Ford and Toyota Motor Corp. have in full-hybrid vehicles.

Continental's ISAD system, as used by GM, costs an estimated $2,500, about $1,000 less than Ford's Escape hybrid system.

ISAD comes in a compact package, requires no large battery and offers as much as 147 lb.-ft. (200 Nm) of extra torque. It also provides a maximum 15 kW of electricity for onboard devices and easily could be migrated across vehicle fleets.

Bob Larsen, director-U.S. Dept. of Energy's Argonne Center for Transportation Research, tells Ward's a mild strategy, which is employed by Honda Motor Co. Ltd. on its Civic and forthcoming Accord hybrids, is the most cost-effective hybrid strategy available. He predicts many auto makers will adopt it in coming years to meet corporate average fuel economy requirements.

Reith admits there are disadvantages to mild-hybrid technology when compared with diesel engines.

Even the mildest of hybrids carry a weight disadvantage, are costly and have yet to deliver consistently high fuel economy, especially on highways.

He says diesel is further along in terms of development and is more accepted by European buyers and auto makers.