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Low Voltage Power Distribution?

Posted by ryuzaki0 on from the wall-wart-motel dept.

thesp asks: "As I look around my apartment, I am continually struck by the plethora of high-voltage AC to low-voltage DC power adapters I use to power my various devices. At a recent estimate, around 30% of the power consumed in my house is via these adapters. From my laptop to my digital music player, and from my mobile telephone to my PDA, each device is down-converting its own power through its own adapter. Double this number to include my partner's devices. Many of these run hot, and are inconvenient to remove/replug to conserve power and outlets. Does Slashdot know of any moves to standardize power delivery to such devices, or of hobby/home-brew projects to distribute low-voltage power from a central power converter? Alternatively, are there reasons as to why this would not be a simple and effective solution to the proliferation of wall-warts." "On closer examination, these adapters seem to fall into four major categories, 7V, 5V and 3V, with the most common being 5V. Despite this, each device uses a different DC plug configuration, which makes efficient use of adapters difficult. It seems to me that, just as AC power is standardised, portable electronics power requirements should be also be standardised, with a standard wall outlet and car outlet at, say, 5V, and a standard device cable and interface. Electronics manufacturers would save money on power adapters, and the consumer would have the cost of the converter written in to home construction or automobile construction costs. No longer would we have to lug 4 separate power adapters with us on an overnight business stay to power our various equipment."

4 of 237 comments (clear)

  1. Low Voltage DUPE distribution? by TripMaster+Monkey · · Score: 4, Informative


    Article is a dupe...original discussion can be found here, which amusingly enough, is itself a dupe of this discussion. Even more amusing is the fact that all of these submissions share the same editor.

    Way to go, Cliff...a dupe hat trick. Zonk has nothing on you.

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    1. Re:Low Voltage DUPE distribution? by RzUpAnmsCwrds · · Score: 3, Informative

      It is VERY hard to change the voltage of DC with high efficiecy

      Not true. DC-DC converters have existed for years, and they are highly efficient. Take, for example, the DC-DC convertor on your motherboard - if it were only 30% efficient, it would be dissipating more heat than the CPU. Fortunately, DC-DC converters are generally closer to 90-95% efficient.

      Take, for example, the picoPSU - it outputs 120W at various voltages (from a DC source) and it doesn't even have a heatsink.

  2. A few reasons... by Tyler+Eaves · · Score: 3, Informative

    1. You can't (simply) transform DC voltage to a different voltage. This can be done very efficiently with AC. The 120v to 5V (or whatever) in your power supply is done before the AC is rectified to DC.

    2. Low voltage == High losses, esp. with DC.

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    TODO: Something witty here...
  3. Re:Ohm's law by toddbu · · Score: 5, Informative
    What distance? A few hundred feet throughout the house? The loss would be neglegible over that distance.

    Depends on your current draw. Check out this table. Remember that by time you wire your entire house, there will be several hundred feet of wire.

    There's a reason we feed houses with AC.

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    If you don't want crime to pay, let the government run it.