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Education Transportation Technology

California District Launches Country's First All-Electric School Bus 94 94

joe5 writes "Well, leave it the golden state. The Kings Canyon (near Squaw Valley) Unified School District recently launched the first all-electric school bus in the United States. The bus is a modified SST Trans Tech model based on a Ford E-Series van chassis — and Motiv Power Systems created the electric drive train. (The project was a collaboration between those two companies plus the California Air Resources Board.) The electric bus can carry 25 students with an estimated range of 80 to 100 miles— and while it costs more than a standard combustion engine version, is expected to save about 16 gallons of fuel per day. Thanks to a federal highway program, three more electric buses are on their way to the Kings Canyon district and similar programs are in the works in both Chicago and New York."
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California District Launches Country's First All-Electric School Bus

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  • Since buses are so big, seems they are a good candidate to add an on-board range extender engine, for those trips that might exceed battery range.

    Also, seems they also have lots of roof surface area where PV could be installed, to also help with range, or running accessories, or charging when just parked in fleet parking lots, or at destinations.

    • by loshwomp (468955)

      PV could be installed, to also help with range

      It doesn't need any "help with range". Fleet vehicles (like school buses) are already a near-ideal case for electrification; they follow well established routes and schedules. Range is either sufficient or not, and once sufficient, the marginal value of additional range is zero.

      • Unless you want to take kids on a field trip...

        • by loshwomp (468955)

          Unless you want to take kids on a field trip...

          It doesn't make any sense to optimize for outlier trips like that, unless you have money to burn. Rather, you keep a few diesel buses around.

          PV is better (economically, for efficiency, and for the grid) when it's stationary and grid-connected, and range extenders negate the benefits of the simple electric powertrain (bringing back ICE maintenance). A "range extended" EV embodies the complexity of both a full-power EV and a convention internal combustion powetrain.

    • by Solandri (704621)
      loshwomp has already addressed the range part. I'll tackle the PV part.

      Diesel has an energy density of 36 MJ/l, or 136 MJ/gallon. If you assume 12 MPG, a school bus driven 100 miles a day will consume 8.3 gallons. With a conversion efficiency of 30% (30% of the energy makes it to the pavement and moves the bus, the rest is lost as heat in the engine, transmission, and tires), that's 136 MJ/gal * 8.3 gal * 0.3 = 339 MJ of energy consumed. Or 3.4 MJ per mile.

      A full-size school bus is about 2.4 mete
      • Capacity factor for the U.S. is about 0.145. That is, for every 1000 Watts of PV you have installed, it'll generate on average 145 Watts throughout the year after factoring in night, weather, angle of the sun, dirt on the panels between washings, etc. So those 28.8 m^2 will actually only generate 3888*0.145 = 536.8 Watts average through the day. 536.8 Watts * 1 day * 24 h/day * 3600 s/h = 36.38 MJ in a day. Or enough to move the bus 10.7 miles per day.

        Or you could just add 10% more batteries to the bus.

        Buse

  • hmmm.... (Score:1, Troll)

    by Connie_Lingus (317691)

    I wonder how much oil and/or coal it takes to create the electricity to charge this bus everyday?

    And yes, I know that CA just opened the worlds largest solar farm [independent.co.uk], but we all know most power on the grid is still carbon-burning.

    • Re: (Score:3, Informative)

      by Anonymous Coward

      Assuming all the energy is generated via coal, it would generate about two thirds of the carbon emissions. On one hand you have vastly improved efficiency of the power plant vs. the diesel engine. On the other hand, petrol is rich in hydrogen which burns to water, while coal is pure carbon so it will generate more CO2 for the same energy. If you use natural gas (CH4), then it drops to about half what the Diesel engine would generate.

      A more realistic view would take the energy whole mix into consideration, w

    • by blueg3 (192743)

      It depends on where you are. In some parts of the US, hydro and nuclear make up a very large part of grid power.

      • Where is most electricity generated in the alternative methods you listed?

        • by blueg3 (192743)

          I'm not sure what you're asking.

          In my area (upstate New York), more than 50% of electricity is made by a combination of nuclear, hydroelectric, and "other renewable". (This last is almost negligible.) The remainder is natural gas and coal, favoring natural gas.

          Of course, we are one of the cleanest-electricity regions of the country. But we're not the only cleaner-electricity region. For example, parts of Tennessee get most of their electricity from hydroelectric.

          Useful links:
          EPA eGrid [epa.gov]
          NYT article [nytimes.com] on the regi

    • by dbIII (701233)
      A bit more than an electric train moving the same weight and a lot less than a 1950s electric "trolleycar" or tram.
      Next question?
    • by riverat1 (1048260)

      California at present gets less than half of its electricity from fossil fuel sources and most of that is from natural gas. According to Wikipedia in 2011 8.4% of their electricity was from coal and 36.5% was from natural gas. I can only presume based on California politics that those percentages have dropped a bit since then.

  • by bill_mcgonigle (4333) * on Saturday March 08, 2014 @03:12PM (#46435531) Homepage Journal

    You can paint it yellow, but it's still a really-short bus. That might make sense for very low-density areas, but I was surprised when I needed to hire a school bus for a Scout event last year that the newer full-sized buses actually get pretty amazing mileage. At 10-15 MPG, it's terrible for a car, but when you're carrying 60+ people, that's fantastic. Especially considering you can still buy a pickup truck that gets similar mileage. I was expecting the answer to come back at "7MPG highway" or something more proportional to automotive mileage.

    Kudos to the anonymous mechanical engineers who design these things. I suspect it would be really hard to build a full-sized EV bus that used less total fuel, considering the transmission and charging losses, and the fuel equivalence for the additional wealth needed to purchase such a thing.

    • newer full-sized buses actually get pretty amazing mileage. At 10-15 MPG

      Wow. Seriously. Compared to what you get with cars, SUV's, etc. that seems amazing. I wonder what accounts for that fantastic efficiency compared to smaller vehicles.

      • Lousy acceleration + diesel engine? Once it gets moving, you only need to power it enough to prevent friction from slowing it down, in which case I would imagine more mass would be an advantage.
      • by dbIII (701233)

        I wonder what accounts for that fantastic efficiency compared to smaller vehicles.

        Seriously competing with an international market instead of assuming consumers will just buy the latest monster SUV out of Detroit.

        They are trucks with a bus body. The sort of people who decide to buy them will gladly get Mercedes, Scania or whatever to build their bus body on if they can save a bit on fuel.

    • by Solandri (704621)

      I suspect it would be really hard to build a full-sized EV bus that used less total fuel, considering the transmission and charging losses, and the fuel equivalence for the additional wealth needed to purchase such a thing.

      I dunno. Consider how much mass school buses have, I would think you could recoup a huge amount of energy with regenerative braking alone. And unlike cars which only stop at red lights and stop signs, school buses also stop at every pickup/drop (every kid's house in rural areas) and a

    • by drinkypoo (153816)

      At 10-15 MPG, it's terrible for a car, but when you're carrying 60+ people, that's fantastic.

      it's not that fantastic. I knew a dude who had a tour bus converted into an RV that would get 10+ MPG pulling two cars on a big trailer. And that's a way heavier bus. The big problem with modern buses is aerodynamics, they have none. Around town it's irrelevant. On the highway it's serious.

  • Because the government is now not getting fuel taxes (in their eyes "losing revenues to tax dodgers"), they'll want to tax it in other ways.
    Miles traveled. Number of kids ferried. ANYTHING so they can make a buck.

  • I've long thought this is an obvious application for electric vehicles, what with predictable routes and whatnot. Another one would be the small local delivery mail trucks, especially as those things are constantly stopping and starting - a very inefficient way to use an ICE, and one which puts a lot of wear on the engine.

    • by Ken_g6 (775014)

      I've long thought this is an obvious application for electric vehicles, what with predictable routes and whatnot. Another one would be the small local delivery mail trucks, especially as those things are constantly stopping and starting - a very inefficient way to use an ICE, and one which puts a lot of wear on the engine.

      You would seem to be [evworld.com] right about that. [usps.com]

    • Another one would be the small local delivery mail trucks, especially as those things are constantly stopping and starting

      I bet they could deliver milk with one of those!

  • Like most stories about electric busses, electric trucks and electric cars, this one includes no useful information about cost. Who thinks that without a taxpayer handout, this thing makes any economic sense to the Kings Canyon Unified School District?

    Pure Pork.

    • by romanval (556418)

      If you're going to think of it in those terms, even a petrol powered school bus is a "hand-out"... Since a brand new diesel-powered school bus can cost around $100K, and the school district will spend that amount (over its lifetime) for maintenance.

  • Something to do with electricity.

    We'll call it the "Short Bus".

  • $400K for a short bus? Sure, it saves $11K per year on fuel costs (minus electric cost which isn't in the story) but still, a conventional bus of that size is around $50K so paying an extra $350K seems like an excessive amount for the extra greenness.

    • by dbIII (701233)
      You Americans seem to hold onto your school buses for 50 years or so, thus it's going to pay for itself eventually :)
  • If the bus has a useful range of 80-100 miles and would otherwise consume 16 gallons to cover those 80-100 miles, that puts the MPG of the bus at between 5-6 MPG...

    Seriously? They drive school buses that are THAT inefficient?

  • It could lead to a new definition of "rolling blackout".

  • Predictable route, with range clearly defined, Times of use also known, recharges inbetween runs, topped up by mains at school/depot if needed. Electric/Solar buses seems like a brilliant idea

  • Wasn't that the show on PBS where Ms. Frizzle jumps out of the bus a yells, "HAY YOU GUYS" ?

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