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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."
I'll say the same thing here that I said on tribe.net when this came up.... How much electricity is "$9 worth"? Is that at 4 cents per kWh, or 25 cents per kWh? Electricity is found at both thos prices, and every price in between, in different places in the US, and I want to know how much electricity this car uses, not how much it costs some undefined person at some undefined location.
www.wavefront-av.com
As long as you get the ultrafluxcapacitor car going at 88 mph, you can go anywhen... ahem anywhere.
Where were you when the voynix came?
$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?
Remember, there were no nuclear weapons before women were allowed to vote.
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."
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?
Behold the future.
Information wants to be anthropomorphized.
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.
This is simply shocking news.
The theory of relativity doesn't work right in Arkansas.
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
Javascript + Nintendo DSi = DSiCade
Exploding laptop batteries are one thing, but exploding fully-charged ultracapacitors, now you are talking real damage.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Energy content of gasoline is 45 MJ/Kg. That means you are storing 1.35e09 Joules of energy. You are charging it in 5 minutes? So dividing by 300 seconds, the Power rating for the charger is 4500000 Watts or 4.5 MW. If you try to charge it from your friendly neighbourhood 110V line, the amp rating for the plug is drum roll please, 40909 Amps
Now think when you are pumping 25 gallons of gas into that Hummer in 3 minutes, you have a 8 MW device in your hands!
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
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 thinking of a system more like this...
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'
The idea of replacing the batteries in electric and hybrid electric cars is not a new one. BMW was at one point determined to use ultracapacitors in it's hybrids, rather than batteries, because without chemical reactions taking place, the storage of electricity is much more efficient than batteries. BMW has apparently abandoned that in their alliance with DCX and GM on their hybrid system, but since BMW hasn't announced any of their own hybrids, we can't exactly tell yet. I believe also that it would allow greater maximum output from a car, if one were so inclined to let a couple/few hundred kilowatts go to the electric motors.
The problem is that the ultra capacitors haven't been quite ultra enough yet. I'm no expert on capacities of capacitors, but you're limited by size/surface area in the capacitor and 'they' seemed to 500 miles is quite a claim, and unless they have a specific car, it's not a usefully specific claim. And if they do have a vehicle, it's best to make sure it's not a lightweight go kart like an Elise (or the new Tesla car, which is an Elise), as those cars tend to not please typical automotive tastes.
There is still potential out there to make much more effective capacitors. I believe MIT students/professors/people of some sort came up with a Carbon Nano-fiber fuzzy capacitor that multiplied many times the surface area inside a capacitor on which the charge is built up by making the charge holding surface out gagillions of those little fibers. That sounded like a hilariously expensive proposition to me, but perhaps it's not as expensive as my imagination makes it out to be, or it could even inspire others to find similar and less expensive ways to make significant advances in the field of ultracapacitors.
At the very least, companies who make outrageous claims like this one bring awareness to different technologies and methodologies such as capacitors vs. batteries. I'll be interested to see if/when someone brings a capacitor driven car to market, be it these guys, or BMW, or whoever.
you cannot dodge the quad laser. jumping is useless.
> $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..
Worse. Imagine a 'gas station' of the future with a dozen 'pumps' hammering away. Imagine the electrical feeder line that will be needed going into the station. Now imagine a city, where 'gas stations' are usually on at least one, perhaps two corners of any major intersection. Now imagine one out on a lonely stretch of Interstate. All hammering away at the electrical grid by the Gigawatt/hour. Where do we get all that additional electricity? With all the major upgrading of infrastructure, increase in power station fuel costs, etc. required I wouldn't expect electric rates to remain constant, that $9 will become $50 by the time it moves from early adopter status to mainstream.... and any remaining savings on the gas bill will be more than offset by the higher electric bill.
If we start a major program of building nuke plants NOW we might be able to get ahead of the demand curve but we will still be looking at a major upgrade of the distribution grid. Everybody will have a megavolt line running through their neighborhood.
Democrat delenda est
5 minutes = 1/12 of an hour. So required current to transfer that much energy in five minutes would be 4909 amps.
Of course, the recharging stations might be very high voltage. High voltage transmission lines are routinely 110 kV and up. At 500 kV, transferring the current might only take 11 minutes. Don't know that I'd want to play around with voltages like that!
What was once true, is no longer so
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.
Let's expand the math for a little bit. First, let's assume a national (USA) average of $0.09/kWh, as that makes the math a little easier. Nine bucks divided by 9 cents per kilowatt-hour equals 100 kilowatt-hours. 100 kilowatt-hours of energy dispensed over five minutes represents a power draw of 1200 kilowatts, or 1.2 megawatts, roughly one one-hundredth the capacity of the now-decomissioned Trojan Nuclear Power Plant near Porland, Oregon. Divide that by the standard US voltage of 240V AC, and you have a current draw of 5000 amps.
That requires some fat-ass wires.
As most homes in the US have a 200A electrical service, this represents the power draw of approximately 25 homes loaded to capacity. Further considering that the National Electrical Code requires that continuous load of a circuit be 20% less than the rating of the circuit (typical peak load would therefore be 160A), and that average peak load will probably be closer to 100A, this battery will represent to the electrical system a load equal to 30-50 homes!
I guess it's time for everyone to build nuclear power plants in their back yards.
Give me my freedom, and I'll take care of my own security, thank you.
Don't forget that only 15-20% of the energy stored in gasoline is converted to mechanical energy to drive the car. The other 80-85% of energy is waste heat.
According to the Wikipedia article on Ultracapacitors>, they have a cycle efficiency of 95%.
I don't want to work that into your calculations, but it amount of energy needed to drive a car X miles is far less that what is contained in a tank of gas that will drive you X miles.
With the first link, the chain is forged.
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.
Pfft. That will barely get you to the store.
Fnord.