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A turning radius of 36 feet is tight for a sports car, let alone a commercial vehicle with a payload up to 2 tons. Photo: Navistar International Corp.

By Paul Abelson

Vehicle: eStar
Manufacturer/distributor: Navistar International Corp.
Class: 2e – 3
Payload: 4,000 pounds
Basic charging requirements: three-phase, 220 V, 32 amps
Manufacturer's suggested retail price: $149,900

Produced through Navistar's joint venture with Modec Limited of the United Kingdom — the Navistar-Modec EV Alliance LLC — the eStar is perfectly suited for meeting the versatility and stop-and-go driving requirements of virtually any public works application.

The basic truck has a 14-foot box van body. A 16-foot box is in the works with flatbeds and stake bed trucks, boom platforms, and shuttle bus body configurations coming next year. In addition to delivery, it can be configured as a mobile workshop, office, or command post. Its maximum 50 mph and 100-mile range limit it to urban use.

Power comes from a 70 kilowatt (kW; about 102 hp) electric motor producing 300 Newton-meters (about 220 pound-feet) of torque.

Unlike an internal combustion engine, an electric motor doesn't have to slip a clutch or fluid coupling to start. It produces maximum torque at zero rpm, which is how such a relatively low-horsepower vehicle can move so briskly. The eStar's motor is controlled for a flat torque curve to more than 2,000 rpm.

There's no clutch, just a simple PRND (park-reverse-neutral-drive) control. Because maximum torque is at low speed, a low gear isn't needed.

Like a diesel-electric hybrid, the regenerative braking system uses the motor to recharge the batteries when slowing in traffic. Regenerative braking slows a vehicle by reclaiming its kinetic energy. Service brakes bring it to a full stop. The eStar uses four-piston front discs and dual servo rear drums.

The suspension is fairly conventional for this vehicle class, with MacPherson struts and a sway bar up front. In the rear, longitudinal trailing arms and a lateral Panhard rod locate the drive axle, sprung by coils.

Charging the batteries using a basic 7 kW (220 V/32-amp) charger takes 8 to 12 hours, depending on daily service. In 2011, a 10-kW charger will shorten that to 6 to 8 hours. For severe service, or for two- or three-shift operations, the battery packs can be removed and replaced in 15 to 20 minutes. Just remove 12 bolts and three connectors.

But what's it like getting to and from a jobsite?

To find out, I drove an eStar from Navistar's facility in Melrose Park, Ill., to the editorial offices of PUBLIC WORKS near Chicago's O'Hare airport, an 8-mile trip. Along the way, I put the truck through its paces, simulating many of the conditions I'd encounter going to a jobsite, including accelerating in city traffic, braking, turning around, and some evasive maneuvering.

Two things were immediately evident: The truck is almost totally silent and visibility is outstanding.

The only noise from the electric motor is a slight whine, possibly from the gears. Vision through the huge curved windshield is remarkable, nearly 180 degrees. The windshield dips in front of the slanted dashboard so drivers see objects or children, always a concern in urban operations, within a few feet of the front bumper.

Entry is from a side door behind the cab, with walk-in access to the seats. Because of the low floor, loading and unloading are easier. Once belted in my seat, I set out to find some of the worst roads along the route (my apologies to any and all road engineers in the Chicagoland area). Ride quality was great on smooth pavement and, after slowing down, acceptable on the rough. The regenerative braking assisted the disc/drum service brakes for quick, sure stops.

Even with a row of parked cars on one side of the street a U-turn was surprisingly easy. I didn't even need to back up. I found a driveway opening, went slowly, and marveled at such a tight turning radius — 36 feet — on such a relatively large vehicle.

I tried a few evasive maneuvers on a four-lane arterial road. The battery pack sits low in the chassis between the rails, rather than on top, keeping the center of gravity low. It handled more like a pickup than a box van.

Power is more than adequate to keep up with traffic. Due to the low-speed torque characteristics of electric motors, I was even able to beat some cars away from stop lights.

Economics of ownership? You'll have to crunch the numbers.

The list price is high for a Class 3 truck, but you don't have to change oil and filters. Diesel bills will decrease, but remember — you'll have to pay for electricity. With zero tailpipe emissions, each eStar reduces greenhouse gas emissions by as much as 10 tons annually, potentially enabling your operation to qualify for incentives from foundations or government agencies.

Funding programs vary by date, state, and locale. Information can be found at the Clean Cities Coalition or the Green Truck Association (part of the National Truck Equipment Association) Web sites. Many incentives involve tax rebates that don't apply directly to government agencies but can be applied for by dealers and negotiated as a price reduction.

Add all that up over the truck's expected service life of 10 to 15 years or more and it may well be worth the extra investment. If it's close, consider driver satisfaction and safety.

The eStar is the first light-duty commercial all-electric vehicle to receive both EPA and California Air Resources Board certification as a clean fuel fleet vehicle. It meets all Federal Motor Vehicles Safety Standards. So far, it's got no competition in its class.

— Paul Abelson (truckwriter@anet.com) is a former director of the Technology and Maintenance Council of the American Trucking Associations, a board member of Truck Writers of North America, and active in the Society of Automotive Engineers.

Click here for a look at some featured hybrid and alternative fuel vehicles.

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