Smith Electric Vehicles has teamed with Trans Tech Bus to roll out a 42-passenger, 26,000lb electric bus, called the Newton eTrans, which it hopes will change the way children get to school every morning.
"Speed and predictability of route is important," Bryan Hansel, CEO of Smith Electric Vehicles, told us. "School buses tend to have very dedicated routes. You know the exact distance that you drive every day, so you don't have to have any concerns about range anxiety."
The duty cycle of a school bus could be well-suited to electrification. The Newton eTrans is expected to go into production in the second quarter of 2012. (Source: Smith Electric Vehicles)
Indeed, Smith is tuned into the idea of route predictability, so much so that the company offers customers a graduated series of lithium-ion battery sizes. Starting at 40kWh, its battery sizes increase in 20kWh increments, up to a maximum of 120kWh. The top-level bus, which carries about 3,000lb of batteries onboard, has a range of about 120 miles, and employs a permanent magnet motor with 150kW of peak power.
Smith's battery cells, configured like saddlebags across the bus's center frame rails, use a lithium iron phosphate chemistry, and are built by A123 Systems. Although the battery packs employ sensors to monitor cell temperatures, they have no active cooling system. If the battery management system "sees" elevated temperatures in any of the cells, it de-powers that part of the pack (although the company said that has never been necessary).
In that respect, electric buses have an advantage over small electric cars that accelerate quickly, Hansel said.
"When you have a smaller battery and need to accelerate more quickly, that's when you need active cooling," he told us. "You tend to get heating because you are trying to draw energy out of a small number of cells very quickly, whereas we have very large batteries, and we pull very little energy out of them."
To build the bus, Smith teamed with Trans Tech Bus. Smith builds the power chassis for the Newton eTrans, while Trans Tech does the body, structural design, and the interior. The two companies believe that the eTrans is the first all-electric school bus.
Wow, what a great idea for applying EV technology. The fact that school bus routes (and even inner city bus routes) have specific routines with little opportunity for variation do make them strong candidates for EV transportation. Problem is what the problem always is: Cost. School systems don't have the budgets to fund these type of vehicles and while many schools sub out bus transportation to private providers, the question is whether they could sustain any additional cost associated with not only the new vehicles, but the infrastructure that would have to go in place to handle the nightly charging.
Very interesting concept, Chuck, and I think it demonstrates the kind of engineering thinking and focus on efficiency solutions that we need more of. It will be interesting to see how much the cost premium is versus diesel-based buses.
Beth, actually the issue is the Total Cost of Ownership (TCO) of a system like this. For new technologies like electric and natural gas driven vehicles (I know these aren't really new, just coming back) this type of application is perfect. I have long advocated that these technologies be mandated for government entities, where appropriate, as a first step. But, the TCO first. Electric vehicles do not need the maintenance that conventional vehicles do. They also do not use diesel fuel, which fluctuates wildly in cost. So, while the article did not give us enough information to make a final determination, there is a good chance that this could be the case. School districts often purchase captial equipment through bond issues, therefore spreading out the cost, so that might not be as big a deal either.
As for the use of these technologies by government agencies, I think that is a great way for the government toevaluate and prove new technologies without mandating them for the private economy. Often local governments have their own refueling infrastructure and their vehicles operate in a limited geography. Thus, if the technology is useful, this helps build an industrial base for it and gives valuable information to potential future users. If it really works, then the private economy will adopt it.
I totally agree with your logic naperlou, but still skeptical that the government has its act together enough to make a solid TCO case for this kind of expenditure. I would love to be proven wrong.
I still see a problem with range anxiety for school buses.
Looking at rural America, what if the fleet of electric school buses plugged into their overnight charging stanchions either at school or more likely in the dooryards of the bus drivers have no commercial power due to an overnight storm? Weather is fine the next morning but school might have to be cancelled since most children may be without reliable bus service.
And what about communities whose nuclear power plant evacuation plans include moving children out of the danger zone via school buses whose mid-day charge might prove insufficient for the unexpected route change and interrupted charging supply?
Good point, Bdcst. Those would be relatively infrequent events, but they do happen inevitably. So instead of just snow days, the school system would have to allow for power-out-last-night days. I have two kids who live in separate rural areas, and power outages due to storms are much more frequent in rural areas than they are in the city.
I agree ith you, Beth. One newspaper cited a 60% cost difference between this and a diesel model. If that's true, it would be very hard to compensate for it.
@bdcst: Your point about the range issue for rural communities is real. I think the key takeaway with that very real reminder is that even with the very benefits the EV buses can deliver, they (and alternative vehicle technology in general) is not a use case for every situation. Rural communities have different circumstances to deal with than an urban school system. Therefore, the backup plans and equipment they'd have to put in place to support a transition to an EV bus fleet would shoot the ROI right in the foot, hence not a sound use case. That said, I do think this has great potential and just because it isn't a fit for some doesn't mean it wouldn't be great to see pockets of adoption out there.
These busses sound good, however they only make any sense in dense city environments where other electric transportation (communter trains, etc.) are already there or would be less expensive to setup and install.
These EVs place a huge (more than several houses) load on the electric grid when they re-charge (if they are to be re-charged in one 'night'). Has anyone looked at the tremendous strain a couple of hundred of these would put on electric infrastructure
Refueling a conventional bus takes an hour. Refueling an EV of this size takes all night and the batteries may require cooling if it is to be recharged in one 'shift'.
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