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.
Electric companies will be anxious to get their power grid loaded and used over night. It would be great if the electric companies could control the time and sequence of overnight charging to help even out grid load. There's an over abundance of electricity available on the grid, starting at about 10:00 at night and ending around 7:00 in the morning.
The comment about a 13 ton school bus needing less surge to get started than a small electric car is taxing my intelligence. A shcool bus driver presses the pedal as hard if not harder than a car driver to get started. Its battery may be larger, but it's still one heck of a load to get going, especially when you've got 40 passengers on board.
bdcst, you raise good points about the viability of this tchnology in rural communities. Here's another potential problem: Some rural communities have multiple children who live as many as ten miles from the school. If you add up the mileage for all the morning pick-ups, and then realize that the bus has to be recharged for all the afternoon drop-offs, the range may not be enough.
School bus range is the least of many school boards' problems these days. Because of falling tax revenues, how far their money will go is. Investing in electric buses is committing to a very long payback. The article says such buses will cost "considerably more" than diesel-fueled buses. This is exactly what will be looked at when it comes to replacing fleets. When school districts by the hundreds are cutting back on essentials such as teachers and upgraded textbooks, going green will not be on their agenda. Sorry. As much as this is to be desired, this isn't the time it will happen in many areas. It will be a matter of the haves and have nots. Those schools who have the revenue will get; those who do not will have to make do with what they got.
Aside from the additional loads on the grid there is a huge problem with electric school bus use, at least in my city, which is that nobody will be able to service them. That will probably mean also that there will be a union electrician required to plug them in for recharging every evening. So the reduced cost of powering the buses will be offset by the much increased costs of every other aspect of owning them. One more question is how would these buses be heated? Electric heat is a poor choice for any application at any time, and fueled heaters would sort of reduce the environmental savings a bit. About the only problem that they would solve would be the range problem.
Innovation must understand the need and should not try to embed the soultion in it. I think this project has really understood the need. 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." This proves that. Good work
It seems to me that the electric bus would also be an excellent place to put solar panels (on the roof). You should be able to get at least 90 watts of panels on the roof to charge the battery with during daylight hours. Even if you lay them flat, could extend the range of the bus by several miles. Just a thought.
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.
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 :)
Tesla Motors plans to roll out a “compelling, affordable electric car” that will sell for about half the price of its high-profile Model S by the end of 2016, company chairman Elon Musk said last week.
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