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Google Calls For Power Supply Design Changes

Posted by ryuzaki0 on from the reality-would-you-mind-shifting-a-bit-for-us dept.

Raindance writes "The New York Times reports that Google is calling 'for a shift from multivoltage power supplies to a single 12-volt standard. Although voltage conversion would still take place on the PC motherboard, the simpler design of the new power supply would make it easier to achieve higher overall efficiencies ... The Google white paper argues that the opportunity for power savings is immense — by deploying the new power supplies in 100 million desktop PC's running eight hours a day, it will be possible to save 40 billion kilowatt-hours over three years, or more than $5 billion at California's energy rates.' This may have something to do with the electricity bill for Google's estimated 450,000 servers."

10 of 377 comments (clear)

  1. No... by rsilvergun · · Score: 5, Insightful

    google hires experts on Electrical Engineering to figure out how to reduce the power bill on those 450,000 servers. Hell, I'm all for it. Less power means less heat means quieter fans (w/o spending an arm/leg on an Antec Sonata or whathaveyou).

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    1. Re:No... by sillivalley · · Score: 5, Interesting

      The early S-100 systems (Altair, Imsai, Poly, Northstar) used linear supplies and ran unregulated DC on the S-100 bus. Most designers aimed for +8 to +9 volts to feed the onboard +5 volt regulators (and the3 volt or so headroom for 7805 regulators). Can't think of any that ran high current AC on the bus. Some systems, such as the Poly, ran a squared-up 60 HZ signal for real-time clocks.

      The heat losses in S-100 on-card linear regulators were immense! That and the weight of the (linear) transformers helped make the Apple ][, with its switching power supply, so popular (I still have an old Poly power transformer; makes a great doorstop).

      Some mainframe computers used the scheme mentioned by others -- polyphase high-frequency AC distribution. High frequency (think 800 Hz) power transformers are small and efficient; that's why switching supplies run at high frequencies (in the hundreds of KHz range).

      Efficiency is not only about wasting less power, it's about generating less heat!

  2. Re:Big ego department by purpledinoz · · Score: 5, Insightful

    I would bet a lot of the employees at Google have Electrical Engineering degrees. Don't underestimate the brain power Google has in its employee base. But the power supply issue they're trying to address isn't a technical challenge, but a political challenge.

  3. Re:What in a modern computer actually uses 12V? by Anonymous Coward · · Score: 5, Insightful

    Video cards use a ton of 12v power, enough that high-end cards get a dedicated connector featuring two wires of it.

  4. I've wanted this for years. by dgatwood · · Score: 5, Insightful

    The ability to have all my machines powered by a heavy cable carrying 12VDC would be pretty useful for several reasons.

    • The UPS could be integrated into the power supply, avoiding lots of energy lost in converting it up to 110VAC and right back down again.
    • The power supply would then be external, where it could be a fanless brick instead of being inside the case where it adds heat that must be dissipated.
    • A switching power supply is theoretically more efficient than a wall wart. If everything were 12V, all those stupid little outboard devices could draw power off of the same supply source, resulting in better overall efficiency. More importantly, I would never let out the magic smoke when I accidentally plug a wall wart into the wrong device. :-)
    • A 12V system can more easily be integrated with solar panels to reduce load on the power grid.

    *sigh*

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  5. here it is by TheSHAD0W · · Score: 5, Informative

    n/m found it.

    http://services.google.com/blog_resources/PSU_whit e_paper.pdf

  6. Re:Big ego department by ve3id · · Score: 5, Insightful

    I have been saying this for years. We lose 10-20 % of energy charging a battery in a UPS with 117V, we lose another 20-30% in the inverter to get it back to 117V, and then we lose another 10% getting the 117V back to usable voltages for the PC.

    It does not take an expert in electrical engineering, just common sense.

    Can I sue google for stealing my idea?

  7. Re:What in a modern computer actually uses 12V? by zootjeff · · Score: 5, Informative

    If you look at just routing 12 volts everywhere, you just would have to put the regulators in the hard drives, and CDROMS so they don't need 3.3 and 5 volts. Then what do you do about +5 Stanby that allows you to hibernate? Do you still need a stand by voltage? It isn't and easy answer and will take the whole industry to adopt it. Checkout formfactors.org for ATX and BTX specifications that Intel is pushing. What's also interesting is the 600 and 700, etc Watt power supplies just keep their 3.3 and 5 volts at around 30 amps max, but keep adding +12V1 +12V2 +12V3, etc.. Looks like the industry is already going to mostly 12 volts for distribution anyway. But don't you still need PS_ON, PowerOK, etc.. You're just trying to phase out the +5 and +3.3, and -12 which hardly any motherboards use these days, and maybe the +5 Standby, then it's going to happen eventually anyway. Most of the power is going on the 12 volt lines anyway, so having inefficient +3.3 and +5 isn't really a big deal. I've studied this for a while as my big hobby is computers in cars, I built a power supply called DSX12V that takes a 8-16 volt input and makes a solid 12v output that I got over 97% efficiency on. This is good for people sticking computers in cars or running them off banks of batteries for solar power applications etc.

  8. Re:What in a modern computer actually uses 12V? by Jahz · · Score: 5, Interesting

    Actually I would bet that Google servers DON'T have a video card, and that all of them have RJ-45 SOL support (or something like it). The reason being that Google has admitted that they fully embrace the commodity distributed server system. Google will periodically host talks at my university where they explain all this in [too much] detail.

    Basically, when a machine fails, it is pulled from the rack and replaced with an identical machine with a cookie cutter image. Kinda like the Borg :)

    When a box fails it is probably instantly detected by some machine monitor and taken offline (think: the 'crop' tenders in the Matrix I). The sysadmins arent going to waste time plugging a video cable into the rack... just pull it. Toss the box into a repair queue and let the tech's put a video card into it if needed. Remeber: 100's of machines fail for them every day. That's a fact from the Google talk in 05.

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  9. This is about voltage to the boards, not the box by Animats · · Score: 5, Interesting

    Most of the postings so far have it all wrong. Google is not proposing 12VDC into a desktop PC or 12VDC distribution within the data center. What they're proposing is that the only DC voltage distributed around a computer case should be 12VDC. Any other voltages needed would be converted on the board that needed it.

    This is called "point of load conversion", and involves small switching regulators near each load. Here's a tutorial on point of load power conversion.

    It's been a long time since CPUs ran directly from the +5 supply. There's already point of load conversion on the motherboard near the CPU. Google just wants to make that work off the +12 supply, and get rid of the current +5/-5/+12/-12 output set.