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    I've thought about trying to build a bike generator. You could just replace the 
    rear wheel of an old bike with a motor, add an energy storage/AC inverter box,
    and presto, you'd have free power (and get good exercise too).

    When I learned how much power can be generated by a human body though, 
    I got discouraged. For instance, a super-fit, Tour de France-caliber bicyclist 
    can sustain about 400 watts over several hours. But even that would barely 
    be enough to run the portable theater.

    The main problem is the projector, with its super-bright lightbulb. A quick 
    google search reveals the average projector consumes about 250 watts. Add 
    a sound system and factor in generator inefficiencies, and you'd probably 
    need Lance Armstrong to power this thing. And he'd be pretty tired by the 
    end of the film.

    For the average "fit" adult, you could count on around 150 to 200 watts being 
    available (after inefficiencies, maybe 100 watts). So you could power the 
    theater with three or four such riders, or maybe 6-7 kids. The effort would be 
    similar to riding a real bike (with wind resistance) at about 20mph for a few 
    hours...

And here's what local alternative energy guru Dave Strenski had to say:

    Human powered generators would be the best option for safety and 'coolness' 
    but can be expensive…

    If I'm reading your mind correctly, this is what you want.

    You can find DIY plans for bike generators here, here, here, and here.

    You can also buy finished bike stands here or here.

    Keep in mind that a healthy/fit person can produce about 100 watts of power 
    for maybe 30 minutes. I think you would need 10 to 20 bikes plus a line of 
    would-be pedelers. Each bike would have it's own small battery to smooth out 
    the power coming from the bike and to handle people switching riders. All the 
    power would then be collected behind the screen (some place safe) and 
    combined and sent to an inverter to convert the DC power to AC to run the 
    projector.

    Sounds like a great event, but would be costly to put on. Maybe you could sell 
    the bike stands after the show to recover some of the costs. I could see 
    people sitting on the Riverside Park's sledding hill watching a movie with a 
    line of bikes in back...

And then there's my friend Eric, who suggests that maybe we just have people bring their own bikes. Or, better yet, we scrap the idea of bikes altogether. He suggests we locate some old paddleboats and create recumbent pedal-power stations. And, as I'm not an engineer, I'm not sure that his would work, but he also seems to think that maybe we could do it with one big crankshaft, where everyone worked together to feed a single generator. I was skeptical, but he reminded me that 3-person bikes exist. So, maybe he's on to something.

So, let's say we want to do this – is it possible to do it now, this spring? As I see it, we'd need at least three working groups to pull it off. One to handle the math, engineering and implementation. One to handle the pr, marketing and fundraising. And one to handle the logistics, permits, etc.

My guess, just looking at the notes from Paul and Dave, is that we could probably do it with 14 bikes, if we had a constant stream of fresh riders to rotate in. I know that we could get 14 used bikes donated. I even suspect that we could find someone here in Ypsi to contribute space to store them and work on them. And, if we're lucky, I bet we could even find some local mechanical types to help us put all the pieces together. So, all we'd really need to do is raise money for the motors and City's $100 fee. My friend Homeless Dave just built out a system in his house (see his video further down) and I suspect he'd be willing to help us cost everything out.

Another approach that may be worth considering is getting a number of local businesses, not-for-profits, high school classes, social groups, neighborhood associations and the like to each sponsor a bike. We could give them the plans, and help them out, but they would each be responsible for getting the bike there on the day of the event, having it staffed with riders, etc. It could be pretty cool.

So, here's the question… Am I stupid to think that this might be possible? Is it unreasonable to think that we can get 20 bike riders to rotate in and out for the duration of a two-hour movie? Is the cost of 14 or more motors going to be too much?

I don't know. There are a lot of components and a lot of unanswered questions. It's exponentially more complicated than something like the Shadow Art Fair, but I think it might be worth it. (I'll tell you more about the Shadow Art Fair in my next post.)

How cool would it be to get something like this off the ground? And, once it's up and running, there's no reason it couldn't be done on a regular basis. (Unless we follow Dave's advice and sell the bikes afterward, which is also a good idea.)

Once all the pieces are together, we could break everything out several times a year if we wanted to. We could even use the bikes to generate energy for other events. We could run the PA at the annual Heritage Festival. We could use it to power the lights at other city-sponsored events. We could even keep them somewhere, like at the Senior Center, for people to charge their phones and laptops with…

I'm sure there are other things that need to be said, but I'm going to leave you now with Homeless Dave's video on bike power while I start my letter to Al Gore (inviting him to Ypsi to show An Inconvenient Truth in the park). Watch it, imagine the possibility of what I've laid out here, and let me know whether or not you'd be interested in helping out. Or, better yet, come on out and have a beer with me this Friday, April 18, at the Corner Brewery. A few of us will be there at 7:00pm, talking about the project.