The 26,000lb bus represents a departure for the electric vehicle market, which has traditionally focused on smaller vehicles. The Tesla Roadster, for example, is a two-seater. The Mitsubishi i MiEV and the Smart ED are sub-compacts, while the Chevy Volt, Nissan Leaf, and Ford Focus range from compact to mid-size. Moreover, most of the vehicles' batteries are either air- or liquid-cooled.
While most auto companies are searching for ways to boost range to 150 miles and beyond, Smith isn't worried about it.
The Newton eTrans electrification system employs a permanent magnet motor rated at 150kW of peak power. (Source: Smith Electric Vehicles)
"Our customers have very dedicated routes," Hansel said. "They know their exact distances, and we size the batteries for the applications." He added that an electric school bus could also be recharged during the day, when the buses aren't in use, as well as at night.
Cost of the buses is expected to be considerably higher than the cost of diesel-based buses, but exact figures are not yet available, as production isn't expected to begin until the second quarter of 2012.
Smith, which specializes in electrification of medium-duty trucks (such as delivery trucks), expects to eventually build a bigger bus with a gross weight of 33,000lb. That bus could hold between 65 and 70 passengers.
"There are always going to be electrification applications that fit nicely in the 100-mile duty cycle," Hansel said. "School buses are one of those applications."
For a close-up look at GM's Chevy Volt, go to the Drive for Innovation site and follow the cross-country journey of EE Life editorial director, Brian Fuller. In the trip sponsored by Avnet Express, Fuller is taking the fire-engine-red Volt to innovation hubs across America, interviewing engineers, entrepreneurs, innovators, and students as he blogs his way across the country.
Wow - I was thinking that the temperature issue was just the effect that cold weather has on a battery (like trying to start your car in the middle of winter). I didn't think about heating, which I am sure is a major draw. Maybe that's another reason the current crop of electric vehicles tend to start at the smaller end. I can't see how they could even heat the volume of a bus off the battery.
You raise another good point, Jack. Weather can make a huge difference for electric vehicles. When Wall Street Journal writer Jonathon Welsh tested the Nissan Leaf in 20-degree weather in 2010, he put just 49.5 miles on the odometer before finding that the remaining range was in the single digits. That's a preciptious drop from its stated range (somewhere between 73 and 100 miles). The culprit was apparently the interior heater. Imagine how much the range would drop on a bus if a driver tried to heat the cabin.
Justajo - I think your comment about the budgets leads into another issue with range anxiety. How much safety factor is going to be built in? Are the school boards going to keep costs contained by looking solely at the range the bus currently drives and buying on that is the closest match? Then the anxiety hits when its cold, unusually bad traffic, the battery starting to wear out....
You write as if the government really has ever worried about the cost of anything. Just borrow the money, write the check and let the next generation worry how to pay for it. I am not very aware of any politician of any party affiliation that is unwilling to kick the can down the road for someone else to worry over.
Early bus designs were much more streamlined and pleasant on the eye than today's buses, even this one. To make a bus slippery the back end has to be tapered like a teardrop. And the front of this bus doesn't have much to suggest it went through any CFD or wind tunnel testing. The design is driven by practicality (how many passengers can fit in a given length) and safety (the front flashing lights have to be visible).
As far as servicability, electric is the way to go. Without the vibration of a diesel, electrics typically have far fewer problems. The electronics can't be any worse a challenge for a mechanic than the ECU on current diesels.
The economics of purchasing and running an electric bus will be the make or break issue. I am in total agreement. 120kWh of batteries would be, IMHO, $2,000/kWh x 120 kWh = $240,000. Hmmm, the banks will love the "gas tank".
However, electric buses do have some advantages. They could actaully drive into the school building since the don't give off any fumes. For special ed or educational field trips the quietness would be a definite plus.
Since electrics have no need for drive shafts or conventional frames I would expect an electric bus to be three feet lower to the ground that a conventional bus and have better weight distribution for better handling and tip over resistance. I would also expect electric buses to have battery modules that can be quickly removed and replaced much like fork lift batteries.
And a certain number of buses in any fleet are used throughout the day, sometimes on unexpected field trips.
The bus shell is innovative -- it doesn't look ugly like every other school bus -- and the range issue is adapted perfectly to the application. That said, Justajo and William K, make critical points about the cost of acquisition and service of these buses. To that I'd add, I don't know how it is in most cities, but in New York and New Jersey, there are a bunch of school buses companies and they're all independent companies which bid for business with the cities and various school boards. So it goes beyond getting school boards to buy these things; there has to be an economic argument at the contractor, which is orders of magnitude harder. So unless there are some special grants involved to test deployment of these electric buses, I think they're going to have a tough row to hoe.
Plus, for kids now in college, Electric School Bus is the name of a CD-based game from Microsoft, where the bus drives around in outer space, not an actual vehicle on the road :)
Good comment about the nighttime charging. With some of the new smart grid applications, the buses could automatically charge at midnight, even if they get plugged in immediately after the school day ends.
Tesla Motors’ $35,000, 200-mile electric car may not revolutionize the auto industry by itself, but it could serve as a starting point for a long, steady climb to a day when half of the world’s vehicles will be plug-ins.
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