Trucks at Work

Medium-duty hybrids

So Emanuel Groll and I are making our way around Daimler AG's test track at its headquarters in Stuttgart, Germany, in the compnay's new Mercedes Benz 7.5 ton Atego diesel-electric hybrid truck. Best thing is that Groll isn't some test engineer plucked from the ranks to play test driver for the day -- oh no. He's the guy Daimler put in charge of making this truck become a reality -- the chief engineer himself -- and though it handles just like any other medium-duty you've ever operated, Groll told me making the Atego hybrid come to life was far from easy.

That's because the parrallel hybrid Atego marries a chassis and diesel engine built by Daimler with a hybrid drive system produced by Mitsubishi Fuso -- a well-known Japanese truck maker in which Daimler owns a controlling stake. Putting those pieces together proved hugely difficult, Groll conceded to me: for starters, the medium-duty hybrid used in Japan uses hyrdaulic brakes, whereas the European Atego has air brakes.

And the brakes are key to the fuel savings one gets from a hybrid, as the system is designed to 'capture' braking energy, then re-use it to 'launch' the vehicle. That's but one reason why hybrids like the Atego can get between a 30% to 40% improvement in fuel economy. "The mechanic integration of all of this is not too hard -- it's putting together the electronics controlling everyhting that proved challenging," Groll explained to me in flawless English. "It took us two years to get all of the components to 'talk' to each other correctly."

DHL is going to get the first Atego hybrid prototypes in the spring of 2008 for some detailed real world tests -- not only measuring fuel savings but maintenance savings, too, as the regenerative braking process should help extend brake pad life. "We haven't had the chance to accumulate that data ourselves, so it will be interesting to see what DHL discovers," Groll told me.

The Atego is but one of many alternative vehicles Daimler put on display for some 200 journalists visiting from 28 countries this week -- garbage trucks running on natural gas, fuel cell powered city buses, diesel-electric hybrid buses, etc. Riding in them, you really don't notice anything too different, though -- less noise of coruse and none of that pungent diesel odor. But aside from that, the ride and handling is no different from their diesel-only counterparts.

Underneath the hood, though, it all gets complicated -- and in terms of keeping them on the road, maintenance is going to be the real issue in the long run, I think. Fuel savings will be there, which should help offset the higher costs of hybrids, but if they prove too complicated or require more downtime for maintenance, money saved from lower fuel bills may go back out the window.

Yet this is all occuring at time when we are staring $100 per barrel oil in the face -- with fears that it may go higher as 2008 dawns upon us. So, even with the complications, medium-duty hybrids like the Atego and others from International, Kenworth, and Peterbilt may end up being the best money-saving option for fleets down the road -- and sooner than we think.