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University Switches To DC Workstations
An anonymous reader writes "Researchers at the University of Bath, UK are undertaking an in-depth study of energy consumption within the new network, with the aim of demonstrating that running a large network of devices on DC rather than AC is both more secure and more energy efficient. AC electric power from the grid is converted to DC and runs 50 specially adapted computers in the University Library. Students using the system have noticed that the new computers are more compact and much quieter than the previous systems. The immediate advantages of the new system are not only for the user but for the energy bill payer and the environment."
Tesla is giggling in his grave
which is totally what she said
The only thing inside a computer that actually runs on AC is the computer's powersupply. The powersupply regulates this to DC voltages! The powersupply is also quite bulky and noisy compared to the other components.
"Initial tests show that the system in Bath emits approximately half as much energy as heat than the previous AC powered system while running much faster."
Yes, I'm sure it'll generate less heat when most of that heat comes from converting AC to DC, but why the hell would it run faster when everything else in the computer is still the same?
Selective quotes from TFA:
Researchers at the University are undertaking an in-depth study of energy consumption within the new network, with the aim of demonstrating that running a large network of devices on DC rather than AC is both more secure and more energy efficient.
The new DC network also offers greater security. DC power supply units have a simpler design, with fewer parts that could fail and need replacing. The system at the University also charges a number of batteries when usage levels are low to allow the system to run independently from the grid for up to eight hours should a cut in power be experienced.
The above two paragraphs are the only I could find in TFA that mention security. I gotta ask -- can anyone speculate how centralizing the PSU would lead to a more secure system? Is it possible that there is a regional definition of "secure" to mean "very reliabile" or "very available." As in, we have "secured" a constant municipal water supply?
I guess I could swing either way on this one.
Todd: I hope it proves as delicious as the farmers that grew them
Too bad, if he was rotating it would probably generate some power.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Edison: "Genius is one percent inspiration and ninety-nine percent perspiration."
Tesla: "If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search. I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety percent of his labor."
Truthfully both approaches are valuable, and we would be a poorer planet without either of these men. It's a shame they disliked each other so much.
Edison: "Genius is one percent inspiration and ninety-nine percent perspiration."
Edison contracted out all his perspiration. That's genius.
Today if you blow a power supply (one of the most common computer failures) you lose one computer. If you blow the power supply for the office floor you might lose 100 or 200 computers.
For reasons which are a long story, I have had several servers up and running on 12V for many years now. The powerstream guys are pretty much the gold standard of ATX 12 volt power supplies, as far as I know:
http://www.powerstream.com/DC-PC-12V.htm
Note that these are "honest wattages" not the "marketing wattages" seen in the AC power industry. The price of a 300 watt DC supply seems high compared to a 100 watt AC supply from China that has a sticker claiming 300 watts. However its not too bad compared to a AC supply that actually only provides 300 watts despite having a sticker labeled 800 watts or a million watts or whatever marketing felt necessary. Also the powerstream supplies, to the best of my knowledge, are some of the few computer power supplies you can buy that do not have forged FCC and UL registries, which is worth something to me. In summary, expensive, but strongly recommend based on years of experience.
Anyway, what happens when the primary rectifier goes down, is my battery bank will run the asterisk PBX and friends for something like half a day, during which time I can source a generator and charger, or perhaps casually purchase a new supply, etc. Also I have multiple supplies any of which could theoretically power the whole works (at a cost of high heat and much shorter capacitor lifetimes, etc). So you Y-cable them to run multiple plants off one supply. Guess what, the same Y cable can be used to run multiple plants off one battery, if one fails. Etc.
Theoretically, I could run the entire phone system off an idling car, assuming you have enough gas in the tank. Unfortunately my entire plant draws just a little too much for the cigarette lighter plug, probably 15 amps total. If I could invest in new phones / new servers / etc and get total plant draw down to 5 amps, not only would my batteries be 1/3 cheaper or last 3 times longer in an outage, but I could also run the works conveniently off a car cig lighter port.
Obviously if you have zero battery capacity then you are instantly in deep doo doo, but given three or so figures of amp-hours you're good to go for a very long time.
Wire everything in Amphenol power poles, exactly like the ham radio guys so you can use their DC products, and keep a stock of extension cords and Y cables and other gadgets. Use fuses, and as a subset of that rule, only use automotive fuses because they are infinitely available. Use 12 volts as your standard because you probably own a mobile 12 volt generator (aka your car). Perhaps if you're in the .mil and have a 24 volt humvee, do 24v instead, whatever.
A DC powered system is frankly pretty straightforward and simple.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Tesla was the one who advocated for AC power. Edison was the one who argued for DC as the safer choice, and publicly electrocuted horses and other animals using AC to show how unsafe it was.
You see? You see? Your stupid minds! Stupid! Stupid!