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Earth Power Transportation News

Ultracapacitor Bus Recharges At Each Stop 419

Posted by kdawson
from the fill-er-up-with-electrons dept.
TechReviewAl writes "A US company and its Chinese partner are piloting a bus powered by ultracapacitors in Washington DC. Ultracapacitors lack the capacity of regular batteries but are considerably cheaper and can be recharge completely in under a minute. Sinautec Automobile Technologies, based in Arlington, VA, and its Chinese partner, Shanghai Aowei Technology Development Company, have spent the past three years demonstrating the approach with 17 municipal buses on the outskirts of Shanghai. The executive director of Sinautec touts the energy efficiency of this approach: 'Even if you use the dirtiest coal plant on the planet [to charge an ultracapacitor], it generates a third of the carbon dioxide of diesel.'"
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Ultracapacitor Bus Recharges At Each Stop

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  • by unkaggregate (855265) on Monday October 19, 2009 @08:27PM (#29802373) Homepage

    the company name says it all!

    *ZAP* Aowei!

    Oh, first post!

  • Next model (Score:5, Funny)

    by Anonymous Coward on Monday October 19, 2009 @08:29PM (#29802397)
    The next model will come with a flux supercapacitor, and will generate several sequels.
    • by Cryacin (657549) on Monday October 19, 2009 @08:56PM (#29802677)
      Is what makes bus travel POSSIBLE!!!
  • Until... (Score:5, Insightful)

    by cosm (1072588) <thecosm3&gmail,com> on Monday October 19, 2009 @08:31PM (#29802415)
    Exxon buys them out, or lobbies against the tech and throws campaign money to the folks that make the municipal decisions, as big oil does with everything else progressive that possibly endangers their energy monopoly.
    • Re: (Score:3, Insightful)

      by Lehk228 (705449)
      if they do it every time then providing an example should be easy.

      go fetch.
      • Re:Until... (Score:4, Informative)

        by Anonymous Coward on Monday October 19, 2009 @08:43PM (#29802553)

        Done and done.

        http://pppad.blogspot.com/2007/05/nimh-held-hostage-by-chevron-texaco.html

    • "Conspiracy theories are popular among those who are more familiar with how Hollywood works than with how real life works." Best quote about conspiracy theories I've heard in a long time. It was said about the birthers and the 9/11 conspiracy theorists.
  • by srothroc (733160) on Monday October 19, 2009 @08:33PM (#29802443) Homepage
    Aren't these, in the end, pretty much the same as a trolley? The bus is really a mini-bus that holds 11 people. It uses 40% as much electricity as a trolley. If you expanded the bus to hold as many people as a trolley can, wouldn't the increase in size and weight (both bus weight and passenger weight) make it use more energy?

    If so, then what's the difference between this and, say, a mini-trolley? I mean, hell, why not ultracapacitor golf carts or something?
    • by MichaelSmith (789609) on Monday October 19, 2009 @08:37PM (#29802501) Homepage Journal

      We have trams (light rail) here in Melbourne. Maybe if you ran the numbers you could take away the overhead cables from most of the network and just charge the trams at stops and intersections. Might be cheaper overall that way.

      • Re: (Score:2, Insightful)

        by PPalmgren (1009823)

        Also, rails and cables don't make sense for a stop that will enver see more than 10 passengers in the outskirts of a city. The economics allow these buses better scalability. This would be nice in the US where suberbia reigns supreme. The only form of mass transit that really works in a city with low land value like mine is buses, because the houses are so spread out.

    • by quanticle (843097) on Monday October 19, 2009 @08:40PM (#29802531) Homepage

      The advantage with a bus is that its much easier to add new stops and routes. You only have to build up the charging station, whereas with a trolley, one has to tear up the road, put in tracks, and build stations.

      • by Trepidity (597) <delirium-slashdo ... g ['ish' in gap]> on Monday October 19, 2009 @09:33PM (#29802939)

        That's both an advantage and a disadvantage, though. It's not only easier to add stops and routes, but to change or remove them. That makes the value of the transit to property owners considerably less--- someone might put up a condo building next to a metro station, confident that the station will be there for decades, but nobody is going to bank on a bus line.

    • Aren't these, in the end, pretty much the same as a trolley? The bus is really a mini-bus that holds 11 people. It uses 40% as much electricity as a trolley. If you expanded the bus to hold as many people as a trolley can, wouldn't the increase in size and weight (both bus weight and passenger weight) make it use more energy?

      If so, then what's the difference between this and, say, a mini-trolley? I mean, hell, why not ultracapacitor golf carts or something?

      Removes the moving-part-inefficiency, disruption, inconvenience, installation cost, maintenance cost, and unsightliness of overhead wires. I'm guessing that these charging ports would be cheaper to install and maintain.

    • by Dan East (318230)

      A bus can drive anywhere. A trolley (as in a real trolley) draws its power continuously from wires. Thus it can only follow predefined routes that require extensive (and expensive and dangerous) infrastructure. This type of fast-charging capacitor system is sort of like a hybrid combining the best features of autonomous buses and externally powered trolleys.

  • No, thanks (Score:5, Funny)

    by willoughby (1367773) on Monday October 19, 2009 @08:34PM (#29802449)
    The cap's are under the seats?! Call me old fashioned (and it won't be the first time) but I'll take a cab, thank you.
  • by timmarhy (659436) on Monday October 19, 2009 @08:34PM (#29802459)
    people said i was crazy when i talked about this a few years ago. the best advatage of UC's is they don't melt when you discharge a huge current as batteries do, hello electric sports cars that kick the shit out of petrol engines.
  • by Anonymous Coward on Monday October 19, 2009 @08:35PM (#29802463)

    Engineer: Sorry, the idea didn't pan out. The battery works, but it's got no capacity. Useless.

    Marketing Guy: What do you mean, no capacity? It can't be zero if it works, right?

    Engineer: Sure, but it gets drained in seconds by any sort of circuit.

    Marketing Guy: They recharge as fast as they drain, right?

    Engineer: Yeah, sure. but...

    Marketing Guy: "Recharges in under a minute". Nothing on the market can match it. When can we ship in volume?

  • Wow (Score:3, Insightful)

    by ShooterNeo (555040) on Monday October 19, 2009 @08:38PM (#29802513)
    Pretty neat. There's tons of other uses for this technology. Among other things, ultra-capacitors are probably the way to go for non plug in hybrids.
  • High potential (Score:3, Insightful)

    by icebike (68054) on Monday October 19, 2009 @08:47PM (#29802593)

    For urban locations where stops are seldom more than a block or two apart this makes for lower infrastructure costs, as no over-street trolly cables are needed.

    The ability to alter routes would also be fairly flexible because you could tie into the power grid anywhere you need to add a station.

    But the amount of power you need to deliver in a short time means that the stations have to have either the ability to acquire and store a massive charge in the between-bus intervals, (their own ultra-capacitors) or the grid inter-tie would really have to be massive enough to dump that much power into the bus in a couple minutes, for as many buses as you need to send down the line in rush hour.

    A shorted capacitor might be fearsome fireworks display.

  • by dido (9125) <dido@NOsPAm.imperium.ph> on Monday October 19, 2009 @08:47PM (#29802595)

    I imagine the streets of many major cities may wind up getting traffic jams very frequently, so what happens if the bus gets stuck in such a one, and it takes an hour or more to get moving again (e.g. vehicular accident further down), or however long it takes to discharge the ultracapacitors? I suppose it may be necessary to install a backup engine that runs on conventional fuel, possibly just to run a generator which will charge the ultracapacitors sufficiently to get to the next stop.

    • Re: (Score:2, Informative)

      it shouldn't use any power just sitting there. capacitors do slowly discharge of their own accord, but an hour in a traffic jam shouldn't be a problem. they will have to turn off the a/c though.

      • by v1 (525388) on Monday October 19, 2009 @09:38PM (#29802973) Homepage Journal

        Most caps can store charge for months or even years. They can store both high current and high voltage, but cannot deliver a sustained current. In that respect they're a bit like a high pressure air tank, where the gas doesn't change state to a liquid in the tank. (like CO2 does, those are called "constant air" tanks, and are more akin to lead acid batteries because they maintain their pressure until almost exhausted) Like an air tank can retain pressure for months without significant loss as long as there's no leak, so can capacitors.

        I work on HV equipment and am all too aware of how capacitors (and things that behave like them... picture tubes in particular) can retain several hundred volts (life threatening) of power for months. Always have to discharge them before working on them, even if they HAVE been unplugged for a month.

        Buses I've been on aren't known for their air conditioning anyway. When the bus is idling in a jam it's just sitting there and consuming almost zero of its power reserves.

    • by Xeth (614132)
      Electric motors don't idle. Kill the climate control if something goes grievously wrong.
      • by ihavnoid (749312)

        Or even better, activate the compressors of the air conditioners only on bus stops. ...However, I'm sort of worried what will happen if the traffic jam is so horrible that the bus runs something around 5km/h, with constant acceleration/deacceleration.

  • by Ellis D. Tripp (755736) on Monday October 19, 2009 @08:54PM (#29802655) Homepage

    Sinautec, as I suspected, is a Chinese firm, with an office in VA.

    http://www.sinautecus.com/contact.html [sinautecus.com]

  • That's nice that "A US company and its Chinese partner" are piloting the bus, but I think it would be much more interesting to know who designed and built it.

    • by citizenr (871508)

      That's nice that "A US company and its Chinese partner" are piloting the bus, but I think it would be much more interesting to know who designed and built it.

      Chinese did, and that "US company" is also Chinese. Now shut up and go to Walmart buy more Chinese stuff.

  • energy density (Score:4, Informative)

    by QuantumG (50515) * <qg@biodome.org> on Monday October 19, 2009 @09:13PM (#29802799) Homepage Journal

    The ultracapacitors are made of activated carbon and have an energy density of six watt-hours per kilogram. (For comparison, a high-performance lithium-ion battery can achieve 200 watt-hours per kilogram.) Clifford Clare, chief executive of Foton America, says another 60 buses will be delivered early next year with ultracapacitors that supply 10 watt-hours per kilogram.

    Or, to put this in more sensible terms. 0.021MJ/kg (0.036MJ/kg next year) for an ultracap vs 0.72MJ/kg for a lithium-ion battery. Aka, the tiny bottom left square in this chart [wikipedia.org]. Compare this to, say, gasoline at 47MJ/kg or even hydrogen at 142MJ/kg and you start to get some idea of why people are excited about "the hydrogen economy".

    • Re: (Score:3, Insightful)

      by ColaMan (37550)

      or even hydrogen at 142MJ/kg and you start to get some idea of why people are excited about "the hydrogen economy".

      Call me when there's a cheap way to store 30kg of hydrogen at STP in a form that can easily be used and stored onboard in a vehicle for at least 4 weeks without losses.

    • Re:energy density (Score:5, Insightful)

      by fnj (64210) on Tuesday October 20, 2009 @02:43AM (#29804643)

      OK, now state the energy-to-mass and energy-to-volume figures of the gasoline PLUS gas tank versus that of the hydrogen PLUS storage matrix. Fact is, petroleum or synfuel equivalent is the most volume-efficient storage mechanism for hydrogen yet devised - not even counting the contribution of the carbon content. One liter of gasoline contains a higher mass of hydrogen than one liter of liquid hydrogen.

      State of the art hydrogen storage systems have a container mass 10x the mass of the contained hydrogen, versus around 0.1x for gasoline tanks. Compressing or liquefying the hydrogen saps a huge amount of the theoretical energy efficiency of the system.

      When you add container weight, petroleum is the most MASS-efficient storage mechanism for hydrogen.

  • by v1 (525388) on Monday October 19, 2009 @09:31PM (#29802915) Homepage Journal

    Last I checked, capacitors have a very long lifespan, many many years compared to what, 5-10 for lead acid and lithium ion. They don't get memory, their performance doesn't degrade over time. And unlike lead acid, they don't mind the vibrations and jolts of being in a vehicle. I'm not aware of any severe temp restrictions on them either - I know for certain that hotter areas of the country have to have different kinds of batteries because of how heat kills batteries. (moreso than cold)

    So that makes them cheaper to run since you don't have to change out batteries for many thousands of dollars every 5-7 years like you do on the hybrid cars.

  • How...... (Score:3, Interesting)

    by elkto (558121) on Monday October 19, 2009 @11:23PM (#29803753)
    "Even if you use the dirtiest coal plant on the planet [to charge an ultracapacitor], it generates a third of the carbon dioxide of diesel.'"

    Petroleum diesel C16H34 or C14H30
    Coal Errrrrr C with variable trace quantities of S, H, O and N.
    Subcritical fossil fuel power plants can achieve 36–40% efficiency. Supercritical designs have efficiencies in the low to mid 40% range, with new "ultra critical" designs using pressures of 4,400 psi (30 MPa) and dual stage reheat reaching about 48% efficiency.

    Ideal diesel efficiency of 56%, but lets stay sane, I keep hearing more along the lines of 35% (Probably BS but real numbers have been banished/obfuscated/hidden somewhere)

    Factor in 15% to 50% (extreme) grid transmission loss, and (ops) 5% to 10% electric motor loss.

    Love the idea of a Ultra Capacitor for a Hybrid, just stop saying silly things. Less CO2, you're funny.

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