Hope or Hype? Hybrids are getting a lot of talk

TORONTO, (May 10, 2004) — Hybrid vehicles are becoming more noticeable on North American Highways these days. And it’s not just funky-looking Honda’s rolling down the roadway, but fleets of diesel-powered, courier, utility, and municipal trucks too.

Diesel-electric and diesel-hydraulic hybrids are in advanced demonstration stages and some are available to buy now.

The best-known embracer of hybrids is FedEx Express, which plans to convert its fleet of 30,000 medium-duty parcel-delivery vans to hybrids within 10 years. It has chosen an Eaton diesel-electric system in a vehicle built by Freightliner Custom Chassis.

In Canada, Purolator Courier and Canada Post are testing diesel-electric hybrid vans designed by Azure Dynamics of Burnaby, B.C. Azure is beginning work with United Parcel Service on another electric hybrid system.

Costs are fuzzy and few suppliers want to quote numbers, partly because they’re likely to come down fast. FedEx Express won’t tell how much more an E-700 hybrid will cost over a W-700 (for walk-in, 700 cubic-foot) van, but says the E-700’s life-cycle cost will be lower.

Some North American public utility and refuse collection fleets are intensely interested in hybrid technologies. Utility companies believe electric hybrids could operate more economically, bring dramatic fuel-efficiency gains, and are quieter than current diesel trucks. The trucks could use smaller diesels because they’d recycle braking energy during on-road driving and they would be enough to generate power for off-road work. Electric motors instead of an engine-driven power take-off would spin hydraulic pumps to run man buckets, derricks and other equipment.

Trash collection trucks make repeated stops and starts, so are prime candidates for powerful hydraulic hybrids. Brake linings now absorb kinetic energy during stops and wear out fast doing it; capturing that energy and using it to launch the trucks and power compacting rams could save considerable amounts of money. Brake linings should last twice as long and perhaps more, tests have shown.

Eaton Corp. is one supplier developing both electric and hydraulic systems because “we believe there are uses for both,” said Sohan Uppal, vice president of technology at Eaton Fluid Power Group. Its HLA, for Hydraulic Launch Assist, produces tremendous torque at startup — 600 foot-pounds by a 6-cubic-inch accumulator and 1,000 foot-pounds by a 15-cubic-inch model — and produces energy faster than electric systems.