Ultracapacitor Bus Recharges At Each Stop

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Ultracapacitor Bus Recharges At Each Stop

Posted by kdawson on Monday October 19, 2009 @12:25PM 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.'"

33 of 419 comments (clear)

They must be powerful... by unkaggregate · 2009-10-19 12:27 · Score: 4, Funny

the company name says it all!
*ZAP* Aowei!
Oh, first post!
Next model by Anonymous Coward · 2009-10-19 12:29 · Score: 5, Funny

The next model will come with a flux supercapacitor, and will generate several sequels.
Until... by cosm · 2009-10-19 12:31 · Score: 5, Insightful

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.

--
'We are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress.' RPF
1. Re:Until... by Anonymous Coward · 2009-10-19 12:43 · Score: 4, Informative
  
  Done and done.
  http://pppad.blogspot.com/2007/05/nimh-held-hostage-by-chevron-texaco.html
2. Re:Until... by Scrameustache · 2009-10-19 12:43 · Score: 5, Interesting
  
  nice tin foil hat.
  Here's a real world example http://greentransportandenergy.blogspot.com/2009/03/great-importance-of-wheel-motors.html
  They had a working prototype, they approached Detroit to get their making-cars expertise... and the project gets quickly scrapped for no apparent reason.
  
  --
  You can't take the sky from me...
3. Re:Until... by redmund · 2009-10-19 13:19 · Score: 5, Informative
  
  He meant Unsprung Weight, or the weight of the wheel and suspension and associated components. http://en.wikipedia.org/wiki/Unsprung_weight
4. Re:Until... by DJRumpy · 2009-10-19 13:34 · Score: 5, Interesting
  
  So what they need to do is reduce the weight of these independent motors, or find a way to place the suspension within the wheel assembly itself. Some kind of circular leaf spring assembly comes immediately to mind. Imagine a wheel axel, surrounded by springs rather than hard 'spokes' that connect it to the rubber.
  Kind of a 2 state suspension system with a small leaf spring system between the actual rubber and the motor, and then a heavier duty suspension between the axels and the rest of the car.
5. Re:Until... by mozumder · 2009-10-19 13:41 · Score: 4, Informative
  
  He won, because you didn't refute the points in his link, but instead gone into a whiny wharrgrbl mode that losers usually do.
  Now, its your turn to prove that energy companies don't hold back technological progress to save their oil business.
  Otherwise, the other guy is beating you.
6. Re:Until... by Dare+nMc · 2009-10-19 14:13 · Score: 4, Interesting
  
  as a engineer having worked on mining trucks for 12years with wheel motors, that page seams very guilty of avoiding context. Komatsu (mostly GE), Liehbier (Siemiens+GE), and Caterpillar all have wheel motored mining vehicles in production. 1) They show no gearing reduction, electric motors are generally very in-efficient at high torque, they mostly run at around 40:1 reduction in real world car app, this kind of gearing reduction is very pricey to create for high torques without lots of space. 2) Electric motors require a very large current to produce those torques (especially if no gearing reduction) and/or lots of windings (lots of weight) big wiring, and difficult power supplies 3) they show no room for excitation of the rotor, this means permanent magnets = rare earth magnets = $$$ + dense weight. 4) very small bearing surface area, lots of spinning mass = lots of momentum = lots of torque when turning, bumps, etc. Front wheels sounds like a very bad idea. 5) single efficiency number is suspicious, as stated above torque is poor efficiency, I do believe the efficiency at higher speeds but not at high torque. 6) sealing against weather/dirt/mud. Even if they get only 4% loss, good luck with cooling that and sealing it at the same time, without dumping the heat into the tires which will already be under trouble (see the suspended weight = extra tire abuse) 7) still no economical battery choice that can make electric cheaper than diesel over the lifetime of a battery.
  That said, I want 2 for my 1970 2WD truck. It has room for them, and I could slap them on get regen braking, and emergency 4WD help. I don't need much help, and since 80% of braking energy is slowing from 75mph to 25mph so I don't care about the torque/efficiency from 25 to 0.
7. Re:Until... by cosm · 2009-10-19 14:43 · Score: 4, Informative
  
  Examples of Exxon's animosity towards green energy, and items outlining their profit motivation:
  1. Exxon records huge profits this year amidst recession: http://www.washingtonpost.com/wp-dyn/content/article/2009/01/30/AR2009013003744.html
  Why not help us out and lower oil prices? Or show interest in alternative energy besides publicity stunts?
  
  2. Exxon's own website: http://www.exxon.com/USA-English/Lubes/Products_Services/Products_Services_Collection.asp
  Not a single service regarding 'green energy'. And this company make billions, but where are the alternative energy options? They don't care. They have the monopoly among many others in the OPEC conglomerate.
  
  3. "In this class action, the class representatives proved that Exxon failed to provide the agreed reduction in wholesale prices...":
  http://www.exxondealerclassaction.com/faq.php3
  
  4. Exxon buys out global-warming, green energy think tank, denies global worming: http://money.cnn.com/2007/02/02/news/companies/exxon_science/index.htm
  
  5. Exxon flips on global warming because the rockafeller tell them they will lose money: http://www.guardian.co.uk/environment/2008/may/28/climatechange.fossilfuels
  
  6. Exxon contaminates water amidst its own scientist suggestions otherwise: http://online.wsj.com/article/SB125598438080394827.html?ru=yahoo&mod=yahoo_hs
  
  7. Oil Congress: http://www.exxposeexxon.com/ExxonMobil_politics.html
  
  8. Overall campaign contributions: http://www.campaignmoney.com/exxon_mobil.asp
  
  7. I know correlation is not causation, but consider the following: Exxon is the largest publicly traded oil company: finance.yahoo.com
  They even state that on their own website. They have flip-flopped on global warming to please politicians, so they can please their constituency. They have donated money to people who have money in their company. Lets see, largest traded oil company, has Washington in it's back pocket, they protect their financial interest over anything else.
  
  --
  'We are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress.' RPF
8. Re:Until... by Dare+nMc · 2009-10-19 14:51 · Score: 4, Informative
  
  I guess I should say how the mining application is different. They are RWD only, with motors inside dually wheels, with a solid axle box between duallys. This gives spacing to the bearings, room for gearing reduction, a good sealed box to push cooling air around everything. Also all diesel generator powered (no batteries) or trolley operated. The suspension is mostly the tires, which limits time at speed. They can go 40+ MPH, but not loaded for anything more than a few minutes, when they stop to dump and reload (may spend half their time loaded, but for short enough times to avoid too much heat buildup.) And only on well maintained roads, at least relative to the diameter of the tires and max speeds allowed.
9. Re:Until... by AaronW · 2009-10-19 15:24 · Score: 4, Interesting
  
  I actually asked a fellow I know who works at Tesla about wheel motors. He basically said it's a bad idea from a performance and handling point of view. The additional weight in the wheels makes the suspension less effective and means that the effect of going over a bump will be a lot harsher. Besides, he said it also would add a lot to the cost since now instead of one motor you need two or four, as well as two or four inverters and a lot more complicated control software. This also would add more weight since each motor needs its own set of magnets and housing. Cooling can also be a problem. It's much cheaper to just use a differential and axles which typically have very little loss with the advantage that the weight is shifted to the car body. It also makes it easy to do things like water cooling for the motor. I suppose one could still use multiple motors located in the body and use axles to get rid of all of the mass in the wheels, but it still adds a lot of unnecessary complexity to the control system and additional cost and less reliability.
  
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  This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
No, thanks by willoughby · 2009-10-19 12:34 · Score: 4, Funny

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.
1. Re:No, thanks by santiago · 2009-10-19 12:42 · Score: 5, Funny
  
  The gasoline-filled tank is under the seats? Call me old fashioned (and it won't be the first time) but I'll take a pennyfarthing, thank you.
2. Re:No, thanks by Tumbleweed · 2009-10-19 13:06 · Score: 5, Funny
  
  Springs and the support post are under the seat? Call me old fashioned (and it won't be the first time) but I'll take a horse, thank you.
3. Re:No, thanks by Waffle+Iron · 2009-10-19 13:09 · Score: 4, Interesting
  
  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.
  "You can't get people to sit over an explosion."
  --Colonel Albert A. Pope, 1890s bicycle and electric car mogul, on the newly introduced internal combustion engines.
4. Re:No, thanks by zippthorne · 2009-10-19 13:15 · Score: 4, Funny
  
  Sharp vertebrae and powerful acids are under the seat? Call me old fashioned (and it won't be the first time) but I'll take a trusty pair of boots, thank you.
  
  --
  Can you be Even More Awesome?!
5. Re:No, thanks by sincewhen · 2009-10-19 13:41 · Score: 4, Funny
  
  Sharp nails and powerful glues are under the feet? Call me old fashioned (and it won't be the first time) but I'll walk around naked, thank you.
  
  --
  -- Braden's law of data: All data spends some of its lifetime in an excel spreadsheet.
6. Re:No, thanks by Ironchew · 2009-10-19 14:24 · Score: 4, Funny
  
  Sharp rocks and powerful scorpions are under the feet? Call me old fashioned (and it won't be the first time) but I'll be carried around on my royal litter, thank you.
7. Re:No, thanks by Anonymous Coward · 2009-10-19 14:48 · Score: 5, Funny
  
  Inherently unstable bipedal locomotion under the hip? Call me old fashioned (and it won't be the first time) but I'll stick to swinging around on vines, thank you.
8. Re:No, thanks by ModernGeek · 2009-10-19 15:06 · Score: 4, Funny
  
  Reliance on arbor infrastructure to get around and possibility of falling to the ground? I'll stick to swimming underwater, thank you.
  
  --
  Sig: I stole this sig.
9. Re:No, thanks by Sasayaki · 2009-10-19 15:23 · Score: 5, Funny
  
  Limited stop options and the serious risk of drowning? Call me old fashioned (and it won't be the first time) but I'll take a Ultracapacitor Bus which recharges at each stop, thank you.
  
  --
  Check out my sci-fi book "Lacuna" at http://goo.gl/MVxX8
been saying this for years by timmarhy · 2009-10-19 12:34 · Score: 4, Insightful

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.

--
If you mod me down, I will become more powerful than you can imagine....
I can see the design review meeting now... by Anonymous Coward · 2009-10-19 12:35 · Score: 5, Funny

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?
Re:Isn't this the same as a trolley? by MichaelSmith · 2009-10-19 12:37 · Score: 4, Interesting

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.

--
http://michaelsmith.id.au
Re:Isn't this the same as a trolley? by quanticle · 2009-10-19 12:40 · Score: 5, Insightful

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.

--
We all know what to do, but we don't know how to get re-elected once we have done it
Re:Title goes here by amRadioHed · 2009-10-19 12:42 · Score: 5, Insightful

Why would you be dead at a red light? If you're not moving then you're motors are drawing power.

--
We hope your rules and wisdom choke you / Now we are one in everlasting peace
The Flux Supercapacitor by Cryacin · 2009-10-19 12:56 · Score: 5, Funny

Is what makes bus travel POSSIBLE!!!

--
Science advances one funeral at a time- Max Planck
Re:What happens in a traffic jam? by v1 · 2009-10-19 13:38 · Score: 5, Informative

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.

--
I work for the Department of Redundancy Department.
An invention from University of Texas at Austin by Taco+Cowboy · 2009-10-19 13:50 · Score: 5, Interesting

http://www.utexas.edu/research/cem/Energy%20Storage%20Composite%20Rotor.html
The University of Texas at Austin Center for Electromechanics (UT-CEM) has developed a 2 kW-hr flywheel battery for energy management on a hybrid electric urban bus. The battery will recover braking energy and store excess energy generated by the prime mover. The flywheel rotor, fabricated from high-strength composites, spins at 36,000 rpm at full charge (~825 m/s tip speed), and is housed in a vacuum enclosure to minimize windage drag. A cross-section of the flywheel system design is shown. Ensuring flywheel safety is a major issue that must be addressed in using flywheels for transportation applications. In support of this activity, the durability tests performed under Phase IV of the DARPA Flywheel Safety Program, focused on this flywheel design.

--
Muchas Gracias, Señor Edward Snowden !
1. Re:An invention from University of Texas at Austin by countertrolling · 2009-10-19 14:57 · Score: 4, Interesting
  
  Think it'll work this time? I kinda prefer the "solid state" nature of the capacitors.
  
  --
  For justice, we must go to Don Corleone
...except the one that makes the busses by GPool · 2009-10-19 17:37 · Score: 5, Informative

Page 2 of TFA:

Buses in the Shanghai pilot are made by Germantown, TN-based Foton America Bus Co, which uses ultracapacitors manufactured by Shanghai Aowei.
Re:energy density by fnj · 2009-10-19 18:43 · Score: 4, Insightful

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.