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Power generation and storage

  1. Mar 25, 2004 #1

    I am unsure which forum is most appropriate for this query but i'll start here. I am interested in building a device which works on the principle of using a stationary bike to drive an electrical generator to produce electricity, and, if practical, store it efficiently. Ultimately the energy produced by peddling the bike (by myself) I would like to use to power a set of 4x55watt flourescent bulbs in my hydroponics setup. I am a complete beginner and therefore do not expect a thorough technical plan on how to build such a setup more a point in the right direction for resources on which you think may be helpful. Also is this project a feasible one or would the power produced via peddling (a reasonable amount of exertion) be futile? Any suggestions would be greatly appreciated.
  2. jcsd
  3. Mar 25, 2004 #2
    Bike Generator

    I'm no expert at all, I'm a beginer too, I was looking for the same thing you were except for a moving bike, My trouble is finding the whole storing concept. by the way if you plan to power up your what sounds like four 8'lights (I am a lighting sales asscociate) your right the do run at 55W but keep in mind they are made to hook up to a 120V AC system. Theres a transformer (balest) that converts it to the voltage and current required. I have no idea weather you can make something that powers straight to the bulbs.

    As for your what you were looking for, here is a good link I found while doing my "research"
    http://users.erols.com/mshaver/bikegen.htm [Broken]

    Good luck, if you find any good info out there let me know
    Last edited by a moderator: May 1, 2017
  4. Mar 25, 2004 #3
    Brilliant! Cheers for the link it had just the type of information I needed. I am also doing my own research and will post my findings from time to time if I find anything useful. Thanks once again.
  5. Mar 25, 2004 #4


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    Staff: Mentor

    DC generator->car battery->inverter->lights.
  6. May 4, 2004 #5


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    Building it off the grid eh?? Sounds like a plan. I hope you've got good insulation, heat sucks.

    Anyhow, russ has it. Bike chain turns a gear on a generator (dc motor) to which the output charges a car battery.

    However, you will probably need some kind of voltage regulator to make sure you don't overcharge the battery.

    Anyhow, hook up an invertor (you can get them at walmart, advance auto, or pretty much anywhere the sales batterys)

    Probably need a beefy invertor, my 750w does pretty good, but only has 2 plugs.

    All in all, you'd probably have about $1000 tied up in the setup. Any ole cheap bike will do the trick. One thing I had considered was rigging the gearing system of a mountain bike on the generator shaft so I could shift gears.

    However, for what I think your trying to do, i do not think it will work. The lights have to be on for quite sometime, and will burn alot of power. If you've nothing better to do then peddle for 6 or 8 hours a day, shoot. The only way I could see it working is if you have some ole horse stamina, popeye legs and can run 2 generators at once charging several batteries at once. One car battery will likely last about 30-45 minutes running a single bulb you describe. You would probably need about 6-10 batterys, which could get costly. You may consider a large industrial battery, or large boat/heavy equipment batteries.
  7. May 6, 2004 #6
    Home power with a stationary bicycle

    Energy cannot be stored efficiently. If it could, no one would bother using grid power; they would simply purchase energy storage devices and then have energy delivered to their homes by truck on a regular basis -- say, monthly or yearly. However, excellent tips regarding storage batteries (and everything else home-power) can be found at Home Power magazine. The short story on batteries is that, for minimum operating cost, you will require high-quality deep-cycle batteries along with high-quality charging and protection circuitry, a well-ventilated room for the batteries to occupy by themselves (sometimes referred to as a "battery closet" or "battery room"), and extensive knowledge on your part regarding the care and upkeep up of industrial-grade storage batteries.

    That is 220 watts, which (roughly accounting for losses in your home-power energy production, storage and translation system) will require about 300 watts of out put on your part. Continuous output at this level is about half of what a farm horse can manage (one horsepower = 748 watts, which is famously an overestimation {by the inventor of the watt and the steam engine, James Watt, to make his engines seem not so unbelievably powerful relative to horses that people might call him a fraud} of the typical ability of that particular draft animal). It would help if you are already a serious athlete with extensive biking experience and legs that look like this. And just like extreme-high-output bicycle riders, you are also going to require relatively massive cooling. This can be handled by your own sweat, but this sweat is going to be streaming out of your body at a high rate -- gallons in short periods of time. You will require regular water intake to adequately replace this fluid loss. You will also require replacement electrolytes, such as ordinary table salt, without which you will quickly die.

    You will require approximately 8000 calories per day to do this work, if the caloric intakes of forest firefighters are good standards to go by of extreme work output. To calculate your food costs, adjust your present food costs to account for any discrepancy between your present caloric intake and the 8000 calorie figure.

    Performing this amount of work every day, you will also significantly shorten your potential lifespan by prematurely burning out your mitochondria. However, you may possibly be able to protect your mitochondria with one or more of the exogenously administerable mitochondrial antioxidants PBN, N-tert-butylhydroxylamine, N-acetyl-carnitine, liopic acid, idebenone, and coenzyme Q10.
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