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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."
What kind of service will allow you to suck down $9 worth of electricity in 5 minutes?
Good point. Let me slap some math on it.
At $0.25/kWh, $9 is 36kWh. You would have to pass 432kW of power. At 120, 240, 480 and 600 volts, this would be a current of 3600A, 1800A, 900A and 720A, respectively.
At $0.04/kWh, it is much worse. At that price, $9 buys 225kWh, which, to pass in 5 minutes, requires a power of 2.7MW. At the same voltages as above, this would be 22.5kA, 11.25kA, 5.63kA and 4.5kA, respectively.
Hell, even at 13.2kV, this would be a fairly big current, somewhere between 32 and 205 Amps.
I'll take the slower charge, thank you very much.
www.wavefront-av.com
Should this become the path the energy comsuming manufacturers take (cars, laptops, tools, etc), anyone who is not familiar with electronics, please tatoo the following thought in your mind for your own sake:
A capacitor can discharge at an equally alarming rate as this charge time suggests. To take a phrase from Mohamar Khadafi in the eighties, you cross this line, you die.
Seriously - discharging a capacitor will kill you instantly without the proper safeguards in place. Get into a choice car-accident where this connection is made and kaboom! It will explode - if you are the connection, you will die.
A tank of gasoline has nothing on a charged capacitor. Just ask any poor fool who has mucked around with the innards of a television set shortly after unplugging it.
You are checking your backups, aren't you?
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.
Gasoline, in liquid form, is not explosive, nor does it burn all that fast. That's why gasoline fires take so damn long to extinguish.
It only becomes a powerful explosive in vapor form. Cars force tiny trickles of it at a time into vapor with carberators or fuel injections systems. Otherwise, the stuff is just as safe to be around as pretty much any flamable liquid, including vodka, paint thinner, lamp oil, etc.
The kind of wattage we are talking about to charge these cars, however, is the sort of thing utility companies typically put barbed-wire fences around to keep people the fuck away from it.
Maybe you could rig up a system where I park my car on a conveyer belt, and go inside the station for a nice cup of coffee while it is pulled into a fully-automated charging station and then rolled out to be boarded when it's done.
Information wants to be anthropomorphized.
> $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
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.
OK -
The patent applied
and received is US Patent: 7,033,406
Feel free to yank the patent off the USPTO web site.
Issue Date: April 25, 2006
(Hopefuly they are not 24 days late.)
Unit described in the patent:
Weight = 336 pounds
Capacitance = 31 Farads
Peak Voltage on the capacitors = 3500 V
Energy stored = 52 KwH
Size of Unit = 1 cubic foot (its in there read the fine print)
The patent also describes an energy distribution system that includes "fuel stations" that use the same capacitor storage, and charges capacitors at the fuel station during graveyard shift. (double conversion losses, but that can be argued, and there are MUCH better ways to do this)
The "ultra fast charging" as per the marketing/media blurbs are commented on in the patent, "if sufficient cooling for the charging and wire interconnect is avaialble...." so the guy writing the patent was aware of the issues with the resistive losses in the system.
The capacitince structures are a ceramic technology, using special dielectrics. A lot of content there on the chemistry and fabrication technology.
Not sure if this is vaporware or the "next big thing" - we shall see.
Jerry
www.effectiveelectrons.com "chips that work" Analog, RF, Mixed Signal
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.