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500 Miles on a 5-Minute Recharge?
ctroutwi writes "In the wake of rising gasoline costs there have been plenty of alternatives seen on the horizon. Including Hybrids, Biofuels, fuel cells and battery powered all electric cars. CNN has recently posted a story about a company (EEStor) that plans on offering UltraCapacitor storage products. The claim being that you charge the ultracapacitor in 5 minutes, with approximately $9 of electricity and then drive 500 miles."
How about a system in which cars connect to electric lines along the highways, like they use for electric busses and trollies, and use ultra-capacitors to get from the highway to your home? The capacitors could charge while you are on the highway, and then you would only need enough charge to go 5-10 miles.
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Hate to see the short that could occur if this car was in the wrong kind of accident.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
I am old enough to remember city streets in places with overhead power lines for this. Its ugly. Why? I get 500 miles on a tank of gas (13.5 gallons and 29 miles to the gallon) so why not just let me pull into a service station, which now takes almost 5 minutes for a full tank, and plug in... charge me $20 for the charge, make the 100% profit ($9 for the elec, $9 profit, 2$ to cover overhead)... I end up better off they end up better off (distribution now done by the existing power lines, no need for trucks) and eventually, when we figure out how to make electricity cleaner (or convert part of of grid to wind or water turbine or whatever) the environment would be better off. Sounds like a win/win/win situtation
I reject your reality
The whole idea behind an ultracapacitor is that it stores significantly more energy than a regular capacitor.
Linky:
http://en.wikipedia.org/wiki/Ultracapacitors
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what kind of a home has a gasoline pump? i'd imagine there would be special places along the roads that you plug into, just like how it works now.
$9 of electricity is about 100 KWh at national average rates. Passing that in 9 minutes gives you an average rate of 1.2 megawatts. What the hell knid of household has the circuit to handle that?
I would be terrified to even stand near such a fueling station, let alone use one or install it in my home.
Imagine the mortal dread of having your 1.2 megawatt car running low on power during a rainstorm.
For all it's potential energy, at least liquid gasoline is relatively stable and safe. Gasoline car crashes generally only cause explosions in the movies. Unless it's an old Ford Pinto, or a truck being tested on NBC's "Dateline."
Information wants to be anthropomorphized.
It's called a MetroCard. Plenty faster, more energy-efficient, and more convenient than a car, and it only costs $76 a month. And you can actually do stuff on your way to work, like read. Try that next time you're stuck in traffic on the so-called "freeway."
And now, a PSA from David Lynch.
I'm not sure about these long distance claims, you would probably need a huge capacitor, but it doesn't matter because really we don't need to go such long distances on a single charge.
How about a system in which cars connect to electric lines along the highways, like they use for electric busses and trollies, and use ultra-capacitors to get from the highway to your home? The capacitors could charge while you are on the highway, and then you would only need enough charge to go 5-10 miles.
I would find a car that does not have a 300+ mile range to be totally unacceptable. Your idea of having the car be attached to a power line is not very practical because there are not many roads that have these kind of power lines. Also, if you have ever watched the bus driver connect and disconnect a bus from these lines, you would realize that this is not a solution that would work for private cars due to the larger number of cars on the road. It would block traffic in an unacceptable way. The reason why busses run on these kinds of lines is typically because of air pollution - often the buses have to go through tunnels where the exhaust would cause huge problems. Also, busses run in major cities which have a legal requirement to reduce pollution to meet EPA requirements.
Busses go on a few known routes over and over. Private cars have a different requirement - they must go on any road for 300+ miles at a time. They must not block traffic.
If someone has developed a storage system for electricity that allows $9 of electricity to be transferred into the storage unit in 5 minutes - that is a huge advancement over the current technology. It would do a lot to make electric cars practical.
Avoid Missing Ball for High Score
Most likely the journalist was just repeating the claim from the manufacturer who found the cheapest electricity available and based hte claim on that. It would indeed be nice to know how much electricity this capacitor holds.
-matthew
"THERE IS NO JUSTICE, THERE IS ONLY ME." -Death
Big Oil companies will never allow the market to go to this product. Over the years there have been great products that went no where to help us reduce our dependence on oil. now why didnt they go anywhere? because three reasons. people not wanting to change and big companies knowing that its cheaper to stay with the status quo and lastly Big Oil companies will go broke trying to change to anything that they are not already doing.
200 amp service * 220 volts (hot-to-hot) = 44,000 watts.
Recharging 100,000 watt-hours in 5 minutes = 1,200,000 watts.
So the answer is, collectively, the mains feeding 27 households.
I'll let someone more familiar with the NEC spec how thick the conductors have to be.
I doubt that the company will be able to fulfill their claims.
I wish that lawn products such as trimmers and mowers would be based on a capacitor. You figure that they would last a life time. In addition, the ability to charge these in a just a minute (on a 110) would be so easy that many ppl would jump at it. Rather than cars, this is a good entry point market for these.
I prefer the "u" in honour as it seems to be missing these days.
The advantage of electricity remains, even if you are still polluting with your power generation facilities.
It is easier to institute stricter pollution control measures at centralized power generation facilities than it is to implement equivalent levels of pollution control in vehicles all over the country. Even very "dirty" methods of producing such power can always be upgraded over time to be less polluting anyways, or possibly even migrate towards emission free power generation. Also, this migration does not have to be instantaneous either, as an incremental change is often much more economical and practical than a single large change anyways. This sort of upgrading would be completely impractical for individual automobile.
Also, it reduces dependancy on foreign oil.
File under 'M' for 'Manic ranting'
Just because they CAN be charged in 5 minutes doesn't mean they HAVE to be charged in 5 minutes. An overnite maintenence charge would probably eliminate the need for service stations for 95% of driving.
Always going forward, 'cause we can't find reverse.
has anyone done the math here??
$9 is a huge amount of electricity in term of charge. passing that through a line in 5 minutes is gonna take one HUGE ass line, and is gonna pose huge dangers.
just my $0.02
A year spent in artificial intelligence is enough to make one believe in God.
Put a capacitor in your home and charge it up at night. Transfer the power to your car in five minutes from your trickle charge capacitor.
Although this still doesn't address the safety issues.
Current and voltage?
You can figure it out if you're willing to make educated guesses.
Assuming 6.2 cents per kilowatt-hour (price in my state), $9 of power is about 145 kilowatt-hours. This energy is delivered in 5 minutes according to the article. 145 KWh / 5 minutes = 1.74 megawatts AVERAGE charging power.
But that's AVERAGE. Because this is a capacitor (albeit an "ultra" one), it charges in an exponential fashion. The peak charging power during the first few seconds of charging is going to be SIGNIFICANTLY higher than 1.74 megawatts. How MUCH higher depends on the impedance of the charging system.
The real value missing here is capacitance. If we knew that, we could work out peak charging currents for given fixed charging voltages, or vice versa. According to Wiki, the "largest capacitance" of an ultra capacitor is 2.6 kilofarads. Using this as a reasonable but arbitrary number, we can set the total energy equal to CV^2 / 2 and figure out the charge voltage: 633 volts.
Okay, so we have a capacitance of 2.6 kilofarads, a charging voltage of 633 volts, and a charging time of 5 minutes. Further, we have to assume some percentage charge on the capacitor -- it never reaches 100% charge because it charges exponentially, so let's say it charges to 99%. We can use that to figure out the impedance of the charging system using the equation for a charging capacitor: 1-exp(-t/RC)=0.99. Let t = 5 minutes, C = 2.6 kilofarads, and we get a charging impedance (value of R) of 0.06 ohms.
Whoo! Now you can compute the peak charging power (at the very beginning of the charge cycle), which is V^2/R = about 6.5 megawatts. That's 10550 amps. And some of that power is lost as heat in the (very large) wires you'll need to do this -- what fraction of the total is lost as heat is left as an exercise for the reader ;-) But suffice it to say, that heat loss will be at a MAXIMUM when the wire resistance is equal to half the charging impedance, so it implies that the resistance of the wire has to be a lot less than 0.03 ohms.
Feel free to work through it using your own numbers pulled from your own butt, if you want.
>The problem is that the ultra capacitors haven't been quite ultra enough yet.
Up to now the advantage of ultracapacitors over batteries has been power density, not energy density. Power == energy / time. Getting energy in and out quickly in modest quantities is wonderful for cars: you can keep up with the spectacular pulse of energy from a panic stop (do the math, you'll be amazed) and power a quick acceleration to freeway speeds. But they've not stored as much energy as a battery so far. You can get a farad cheap, but they've been limited to low voltages (e.g. 3.6) and energy storage is linear in capacitance but quadratic in voltage.
If these people are storing as much total energy as a battery pack they've made a breakthrough.
What ratio would you propose? 1000A at a mere 60KV (many industrial sites use 30KV distribution lines - strung out with 2' long insulators)? You'd need a monster cable and a 2' air gap around it. You probably can't go much over 1-2KV in practice (I'm no expert, but if 30KV towers have huge insulators to ensure an air gap you can't go anywhere near that), so now you're talking 10KA - that is a LOT of current. You'd need very low resistance to avoid melting the cable.
60 Megawatts is the kind of power that is transmitted over towers. There is no easy way to transmit that kind of power unless you have superconductors.
Agreed that you can trade-off volts for amps - but any way you slice it you have a big problem at those power levels.