Bike for Power!

The OHM is a hand-held sized energy device for cyclists. As it’s explained below, this device uses magnets and a dynamo to collect energy which can in turn be used to power up your phone or other chargeable device. Now you too can declare yourself independent of power plugs and cigarette lighters forever!

The designer, Xavier Unwin, explains the OHM as such:
“Based on electromagnetic induction, ohm harvests, stores and converts human power into usable energy.

1. The user attaches ohm magnets to bicycle wheel spokes. The N42 neodymium magnets provide the optimal balance of durability and magnet strength (current output).

2. The user fixes ohm holder to bicycle seat stays, ensuring the holder is in line with the ohm magnets. The ohm energy device is then placed inside the holder to provide protection from dirt and moisture.

3. The user begins to cycle. As the wheel spokes turn, the magnets pass the ohm internal coil of wire (dynamo) inducing a current. The current is stored in the internal 1200 mAh lithium ion battery.

4. Once the user finishes cycling, the ohm energy device can be removed and used to recharge, with suitable adapters, any portable electronic device under 5 volts. Approximately 45 minutes to an hour of cycling produces enough energy to fully recharge a mobile phone.”

As with all bicycle devices, the OHM is subject of the scrutiny of the riders who have been victim of bike theft; bikes sit out in the open quite often, how realistic is it to attach any device to a bike without fear of it being thieved? Perhaps making the magnets look like baseball cards or the like: things that don’t look shiny and black-market-worthy.

On the other hand, charging up your electronic stuff with your own blood sweat and tears is totally steampunk. Also, how awesome is the dynamo? Power up your mouse-sized Iron Man suit much?

Designer: Xavier Unwin


  • LJN says:

    This would be perfect for me. Gimme gimme!

  • 11hawkinst says:

    This would be perfect for my bike ride to work! I’m sure 15 miles each way would be plenty to charge it, but to bad winters comin’ up and it’s only a concept :p

  • tech-tard says:

    Why can’t this be applied to shoes so that when they pass each other while you’re walking it generates a little juice?

    • Mr.DuckSauce says:

      That sounds like a good idea that also goes with dance floors that generates electricity when people dance on it.

  • craighyatt says:

    I have been looking for something like this. I was thinking of putting a model plane prop on a little motor to generate juice, but the magnet idea is more elegant.

  • Felix26591 says:

    Perfect for my mountain biking, take it out for long periods of time keep ipod charged all the way

  • powers says:

    As long as it’s easy to take on and off I don’t see why theft would be a problem as it’s small enough to toss in a pocket while grabbing a grandé frappé. This is such an obvious concept I would be surprised if it was the first of it’s kind, but you never know. There are bicycle wheels with hub generators. Might as well build the functionality into the bike – but that’s just me; I hate having stuff in my pockets.

    • zippyflounder says:

      versions of these have been around for a longgggggg time, in fact if you have a cycle computer (time, speed, distance) there is a little tiny one that counts wheel rotation. The problem with these is simple, power output, its generaly very small. The power output is a function of the magnetic field strenth (number, strenght, airgap) and coil size. If you wanted to build one, its not hard, a hand full of super magnets, a coil of wire and a diode…but dont be surprized that your going to need a lot of “stuff” to get even a few milli amps out.

  • Texlenin says:

    Already been done! check out:
    Not quite as slick, but cheap

  • Chris says:

    Umm, why attach something to your spokes/fork that could easily become misaligned when there are generator hubs (see ) that are well engineered and are relatively maintenance-free.

    Only thing this concept has going for it is the battery.

    Oh keep in mind the power generated is proportional to how fast the wheel is moving. Hopefully the charger unit takes this into account.

    Good concept, if I could hook this up to a dynamo hub I would love it.

  • Josef Lim says:

    Where is this available?

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