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Ultracapacitor Bus Recharges At Each Stop
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.'"
Done and done.
http://pppad.blogspot.com/2007/05/nimh-held-hostage-by-chevron-texaco.html
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. 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".
How we know is more important than what we know.
He meant Unsprung Weight, or the weight of the wheel and suspension and associated components. http://en.wikipedia.org/wiki/Unsprung_weight
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.
I work for the Department of Redundancy Department.
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.
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.
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
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.
Page 2 of TFA:
I worked for Shell UK in the late 70s, using Univac 1108 and 1110 machines.
They had rows and rows of drum store, each a 1/4 ton cylinder, maybe 1m diameter, rotating at 20,000 rpm. Fixed heads running in a strip down the side, a form of memory somewhere between main and disk, allowing full memory dumps during crash.
They used to take 3 hrs to power up, and Univac engineers used to describe how, if they came off their bearings the outcome was called 'creaming'.
Apparently one came off on a site and 'walked' out of the machine room, pausing only to stroll through a CAU (command Arithmetic Unit - a device as big as a wardrobe), another drilled down through a building.