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Was Thomas Edison Right about DC Power?
Declan McCullagh writes "Everyone knows the alternating vs. direct current wars ended with Thomas Edison and Nikola Tesla. But now DC power is being seriously considered for data centers. DC advocates say that plugging servers into AC power is inefficient, and switching to DC cuts down on waste heat and component failure. The University of Florida has even bought 200 DC servers."
I heard of this new power system. Seems like a mix of AC and DC, to create the ultimate power form. AC *lightningbolt* DC was the name, and with a lightning bolt in the name, it has to strike you like thunder.
Brilliant!
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Uhh.. is a fucking arrogant subject line and even worse when you're fucking wrong.
"Ever try to drive a nail with a screwdriver?"
Nope, but I've put in screws with a hammer, even when I had a screwdriver on hand.
I used to read Caltizzle. I was a lot cooler than you.
Wrap the casket in copper, replace the headstone with a magnet, and expose corpse to this article. As Tesla turns in grave, free power.
As long as there is a Second Amendment, there will always be a First Amendment.
Back in black!
Yes, I'm back in black!
[tap tap]
Hey, who turned off the microphone?
In other news, astrophysicists have announced that they now know what all that dark matter is: it's stupidity.
"220, 240. Whatever it takes."
"The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
I don't understand this whole issue with AC and DC. Both require massive investments in overhead wiring, which despoils the beauty of our suburbia, causes copper shortages, introduces losses from line transmission, requires odd things to be done to trees, and gives birds a comfortable place to sit directly above your car.
Why not just deliver the electricity off a truck like everything else in life? This country has gotten so "addicted" to current electricity that we've forgotten that static electricity even exists. A single charged capacitor can supply enough power to run a modern datacenter; the only limitation is capacitance. Say your datacenter runs on 10 kilowatts (that's just a guess) so you need 240 kWh of power a day, or 864,000,000 Joules of energy. Can a capacitor deliver that amount of power?
Sure it can, if it has enough capacitance. Energy storage is 0.5*C*V^2. Say the cap is 1 Farad, and we choose a reasonable charge voltage of 500 kV. How much energy is that? 125,000,000,000 Joules! WOW! That will keep you all set for 144.675926 days of continuous uptime! Every couple months, the electricity truck arrives and delivers your charged cap, and you give your spent cap back to the electricity man to be recharged at some high-sulfur coal plant in another state. (That means recycling which will help get the "greens" on board.)
Of course then, you have the nitpickers. "But what about the gasoline for the truck? Isn't that a wasteful means of electricity transmission?" Just use the energy in the caps to run the truck! It's like hydrogen! Hydrogen has already been shown to be politically viable.
Is this a new Slashdot cliche in the works? Will it be added to soviet russia, elderly koreans and the like?
In Soviet Korea, elderly dead people spin YOU!
Considering that it would be storing the energy equivalent of 30 tons of TNT, if you were to notice the lid starting to bulge on that cap, it would be wise to run like hell.
Considering that many rural homes have large above ground propane tanks that store a sizable fraction of that energy in the backyard, I don't see a problem. A 350 gallon propane tank is storing about 32,200,000Btu. That is 33,972,799,980J or roughly a quarter of the speculative 144 day capacitor backup.
That tank is also equivalant to a bit over 8 tons of TNT to continue the sensationalist stats. Good god, they let just about anyone have these things! I used to play on one as a child and bang it with sticks and tools because it made a cool sound! [sarcasm]Where the hell is Homeland Security! We must eliminate this terror threat from our counties![/sarcasm]
1 ton of TNT = 4.185x10^9 Joules
1 gallon of Propane = 92,000 Btu
92,000 Btu = 97,065,142.8 Joules