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Cooking With Your USB Ports 188

tekgoblin writes "Wow, I would never have thought to try and cook food with the power that a standard USB port provides, but someone did. A standard port provides 5V of power, give or take a little. I am not even sure what it takes to heat a small hotplate, but I am sure it is more than 5V. It looks like the guy tied together around 30 USB cables powered by his PC to power this small hotplate. But believe it or not, it seems to have cooked the meat perfectly."


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Cooking With Your USB Ports

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  • by Albert Sandberg ( 315235 ) on Sunday October 17, 2010 @11:21AM (#33924038) Homepage

    Watt is. The important is how much current he can get from supplied voltage. In any case why not just use the fucking stove.

    • Re: (Score:1, Funny)

      by Anonymous Coward

      I hear a lightbulb works just fine too.

    • Re: (Score:1, Insightful)

      by Anonymous Coward

      "provides around 5V of power"

      I always knew Slashdot is full of uneducated freetards...

    • Re: (Score:3, Informative)

      by Anonymous Coward

      According to Wikipedia, 500mA per USB2.0 port.
      15A * 5V = 75W

      • Not much to work with there--even the old Easy Bake Ovens used a 100 W bulb, although it probably wasn't that efficient.

        • Umm...*sigh*

          As your AC replier said with less gumption: do you even know how an incandescent bulb works? I mean, you do know that when a circuit is inefficient the wasted power is HEAT right? And, you must also know of course, that with an incandescent bulb all of the non-wasted power is...HEAT, right? What I'm trying to say is that an incandescent bulb is nearly 100% efficient (or nearly 100% inefficient, since all power is radiated as waste heat).

      • Re: (Score:3, Informative)

        by hitmark ( 640295 )

        If it uses the recent battery charging spec, each port can allow 1.5A if there is little to no data traffic (and 1.8A if the data connectors at the female port is shorted with up to 200 ohm resistance).

        • by Barny ( 103770 )

          Sir, you scare the living bajeezus out of me for knowing exactly how much juice you can drain from a USB port.

          Never, and I mean NEVER come anywhere near the computer store where I work please!

          Although at least you wouldn't be like the tool who run 3 unpowered USB hubs, plug in 3 ipods, a mobile phone and a USB powered toaster (who the FUCK though those were a good idea) and wondered why their computer doesn't work any more.

          • by hitmark ( 640295 )

            Heh, i read wikipedia...

            So your saying the hubs, ipods, phone and toaster where all plugged into the usb ports of the computer directly? As plugging them into the other stuff into the usb hub should result in nothing more then ignored devices if they asked for to much juice. At least if both the devices and the hubs where well behaved. I can't get 2.5 drive to spin up unless i plug it into the pc directly or a powered hub.

            • by Barny ( 103770 )

              Are you using a single USB cable to run it or one of those split ones that lets it draw from 2 ports?

              Because no matter which, plugging both connections or a single connection into an un-powered hub means your trying to suck 2-3A from a 1.5A source, a source that as you know has over-current protection ;)

              If a single lead connector works on a PC but not the hub, likely the PCs motherboard is a little more tolerant of devices over-drawing (I know Gigabyte are now doing some motherboards that can pump quite a f

              • by hitmark ( 640295 )

                Single cable, never even bothered trying with a Y-cable as that will by definition not work if the hub is un-powered.

                And yes, it could be a case of the motherboard being a bit more tolerant. Hard to say without attaching a multimeter and perhaps running a protocol sniffer while attaching the drive to the hub, and then comparing that to attaching it to a motherboard port.

                Still, the drive in question specifically came with a non-Y cable. So it should not require a tolerant port, unless QA at the company sucks

                • by adolf ( 21054 )

                  Wrong assumptions.

                  An unpowered hub is not just a ball of wirenuts -- there's logic in there that needs power, too.

                  So, imagine it if you will:

                  Assume that the drive wants 500mA to spin up, and works fine when plugged into a PC, or into a powered hub.

                  Now, put a non-powered hub in series with it. Assume that the powered hub itself wants 100mA just for itself.

                  And, voila! 600mA worth of current draw, from a port specified to only supply 500mA.

                  Now, since in practice USB is all over the map with regards to availa

                  • by hitmark ( 640295 )

                    Points well made, and something i should have thought of myself. Not sure why it slipped my mind.

                    • by Barny ( 103770 )

                      500mA was USB1.1

                      But of course the rule still applies, a hub is likely pre-programmed to split the juice evenly rather than use something likely more expensive and do it properly (dynamic allocation).

                      Bravo to Mr Adolf, good find sir :)

      • Nope. Only 100mA unless you handshake with the computer to request more which he probably didnt do.

    • Re: (Score:3, Funny)

      by arth1 ( 260657 )

      Each powered USB hub supplies a maximum of 0.5 A. Using two or four USB cables against the same hub won't increase that.
      The voltage in USB is a constant +5V.

      So from each powered hub, you can get 0.5 A * 5 V = 2.5 W. Eight of those gives you 20 W, which should be enough to crisp bacon if you make the frying area small enough.

      But hooking up multiple USB cables to each hub serves little purpose (well, you lower the overall resistance a tiny bit, and I guess HiFi freaks would say that it makes the bacon more

      • Re: (Score:3, Interesting)

        isnt the current limited to 100mA per port if the device doesnt identify itself?
        • Re: (Score:3, Interesting)

          per USB spec yes, but there are plenty of hubs/ports which supply the full 500mA regardless

          honestly though, this hack is pointless, you might as well get a cheap ass 350w computer PSU, hook up the 12v to a hotplate and hotwire the thing, much easier

          • You're right. That's much less pointless than just plugging the hotplate into the outlet the PSU is plugged into.

          • Re: (Score:3, Insightful)

            by JWSmythe ( 446288 )

                Why go through the conversion losses at all? Just plug a hotplate into the wall.

              Every conversion has losses. That's why the power supply has heat sinks inside, and usually a fan. It's also why wall warts get warm.

        • by hitmark ( 640295 )

          With the recent interest in using USB as a universal charger port, there is also a added spec for 2.0 and later that allows upto 1.5A if there is little to no traffic on the port in question.

      • Re: (Score:3, Interesting)

        by hitmark ( 640295 )

        Err, no. If the hub is powered, it should be capable of delivering .5A to each port.

        If not, then the dual plug cables we see for some external drives would be useless.

    • Re: (Score:2, Funny)

      by Russ1642 ( 1087959 )
      You have to climb a flight of stairs to get to the kitchen.
    • Re: (Score:1, Insightful)

      by Anonymous Coward

      Watt is. The important is how much current he can get from supplied voltage. In any case why not just use the fucking stove.

      HA! Bitter much?

      I'm sure he was not looking for the simplest way to cook, but just for something new and fun. Looks like he got both. I say mad props to him.

      • I'm all in favor of public hangings for adults who can't get their units straight. It would have saved at least one innocent space probe.

        If you're wondering whether I'm sarcastic: I'm not sure...

    • by hjf ( 703092 )

      USB supplies 100mA 5V, and after negotiation from the USB device and host, and if the host has available power, it can send up to 500mA (in some hosts, like Gigabyte 3x boards this is over 1A). This depends on the controller and drivers - some controllers just send 500mA if available, while others are more zealous and will cut the power if it's over 100mA.

      Assuming it's all standard, this guy is getting 30 ports x 100mA => 3A. 3A x 5V = 15W. or if the host is supplying 500mA per port, 75W. I'd like to kno

      • by ngg ( 193578 )
        (Physicist here) That's correct, though in practice most powered hubs will let you take 500 mA per port without negotiation, and the newer ones that support the USB 2.0 charging spec will let you take even more (~1.8A if you touch the data lines just right). The voltage is also allowed to sag, IIRC, 5% and still be in spec, so assume 4.75 V. That gives a power of 4.75 V * 1.8 A = 8.5 W per port. Times 30, and you could have around 250 W of cooking power. Some of the cheaper hubs (which don't follow the
    • by mayberry42 ( 1604077 ) on Sunday October 17, 2010 @11:46AM (#33924228)

      ...In any case why not just use the fucking stove.

      Because some people enjoy the challenge of creating something fun, new, original and, yes, pointless.

      • Because some people enjoy the challenge of creating something fun, new, original and, yes, pointless.

        ...I'm sure it was fun and pointless, but as fo for the new and original...

        http://www.stylehive.com/bookmark/thinkgeek-usb-mug-warmer-hub-59352 [stylehive.com]

        That's like saying 5 blades is "new, original" compared to 4 blades.

      • by IICV ( 652597 )

        But this isn't pointless-cool, this is pointless-stupid. It would be cool if, say, he'd run power from, say, the PSU's 12v rail - you could actually hook that up, and maybe do a neat little case mod to expose the plug to the outside world. 30 USB ports, though? Where are you going to get 30 USB ports from? And plugging them all in has got to be a pain in the ass.

      • by GF678 ( 1453005 )

        Because some people enjoy the challenge of creating something fun, new, original and, yes, pointless.

        I think there are enough opportunities out there for people to enjoy the challenge of creating something fun, new, original and USEFUL. We have tons of pointless crap done every day that gets attention. I like reading about useful developments more, if they came from a challenge.

    • Re: (Score:2, Funny)

      by sirlatrom ( 1162081 )
      Because the fucking stove is for fucking?
    • by arielCo ( 995647 )

      In any case why not just use the fucking stove.

      Better yet, use the regular one [xkcd.com].

    • That is what I feel every time someone talks about climbing Everest. Why not develop a high altitude Everest class helicopter. Then someone can even setup a penthouse on Everest and arrange tourists to visit ( like the Russians are doing with that "Most Expensive Motel" AKA International Space Station)
    • "In any case why not just use the fucking stove."

      The fucking stove is for fucking, not cooking. Eww.

    • In any case why not just use the fucking stove.

      You must be new here.

    • by b4upoo ( 166390 )

      In a well insulated, very small, oven with a very,very long cooking time it is possible to cook almost anything.

    • Assuming standard USB ports: 5V * (500mA * 30 cables) = 5V * 15000mA = 5V * 15A = 75W. 75W could very easily heat up nichrome or similar materials enough to cook meat (ever used a hot wire cutter? the ones for Styrofoam run on single 1.5V cells! nichrome!).
    • Wot?

  • by Scareduck ( 177470 ) on Sunday October 17, 2010 @11:25AM (#33924060) Homepage Journal
    Volts measure electromotive force, not power. Watts measure power. I would think nerds would know this.
    • I wonder how many parsecs it takes to cook a whole turkey with this.
  • Where's my USB toaster?!?!
  • WTF? (Score:3, Insightful)

    by Anonymous Coward on Sunday October 17, 2010 @11:26AM (#33924074)

    This is the ALL TIME stupidest use for a computer i have ever seen and the most useless Slashdot article as well

    • This is the ALL TIME stupidest use for a computer i have ever seen and the most useless Slashdot article as well

      Definitely some kind of record.

    • Re:WTF? (Score:5, Insightful)

      by SpeZek ( 970136 ) on Sunday October 17, 2010 @12:27PM (#33924414) Journal
      You must be new here.
      • Indeed! Especially as this is a dupe. I remember seeing this on Slashdot a couple of years ago. It seemed a stupid idea then, and guess what, it seems to be a stupid idea now.

        I don't feel like this has much hack value really. Stringing $number of USB ports in parallel isn't particularly hard, it's not a particularly elegant solution (which is one of the things I put down as being key to calling something a "hack"), and it doesn't solve a problem in an smart way. I don't know if it was fun to do (because th

    • This is the ALL TIME stupidest use for a computer i have ever seen and the most useless Slashdot article as well

      With the time it took him to cook the meal...how many porn segments did he watch?

  • The secret ingredient on Iron Chef...Kobe Beef and 5 USB ports.
  • 5 volts of power? (Score:1, Redundant)

    by Sam H ( 3979 )

    I heard USB power was actually OVER 9000!!!

  • by netsavior ( 627338 ) on Sunday October 17, 2010 @11:36AM (#33924170)
    "your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should."
  • by wjh31 ( 1372867 ) on Sunday October 17, 2010 @11:43AM (#33924204) Homepage
    not only has the gizmodo article disappeared at time of post, but there is no link to the original blog post (http://xe.bz/aho/24/) which is date-stamped for 2006. This is 4 years old!
  • one word to describe this story from me: why?

    • two words: why not?

      • why not? Because it is really stupid? Because preparing food this way is stupid? Because it's stupid in a number of ways? Because there is nothing interesting in it?

        I'd be more amused by seeing some sort of a smart stove device, maybe solar powered or some way that actually is useful, this was useless and stupid.

  • Was too busy texting his buddies when his highschool teacher was explaining Ohm's law, etc.

  • if you buy a new motherboard. Because you fried it with your cooking stunt. [OK] [Cancel]''

  • For the comfort and safety of all passengers, if you are unsure as to whether or not a specific device or periferal is approved for use during the flight, please check with your flight attendant before using it.
  • 5V of power (Score:2, Informative)

    by Anonymous Coward

    Volts are not a measurement of power, I am amazed at the number of people who don't understand this.

  • So we have an article on Slashdot about someone used 30 USB ports to cook some bacon?

    Wow. Have we stooped to a new low?

    What does this article tell me? I'll tell you what it tells me; USB is woefully underpowered. I won't stop campaigning until it takes only one USB port to do the same. If I want to have a bacon sandwich from my laptop without moving from the comfort of my easy chair, then it would take an electrocution from the flying spaghetti monster to stop me.

  • For those who still have landline phones, Mike Sandman, purveyor of genuinely indispensable old-school telephony gear, has some telco line powered goodies. [sandman.com]

    Don't even try to order any of them, though.
  • but I didn't expect a story from over 4 years ago. For those of you who can read japanese the original blog post is here [xe.bz].
  • Don't forget your Thanko 80 port USB hub [akihabaranews.com].

A consultant is a person who borrows your watch, tells you what time it is, pockets the watch, and sends you a bill for it.