pedal generator

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Permalink Reply by Ali on April 6, 2009 at 10:24am

I grew up working/living on sailboats, and am quite familiar with heating/solar power and DC systems. Heating has always been an issue on boats whether it is heating of living spaces, heating the water or any other. Heating by electricity requires a lot, let me rephrase; A LOT of energy. This is exactly the reason why sailors use different methods of heating other than electricity.

Take an exceptional cyclist for example, he will be generating somewhere between 300-400W of constant power output, bear in mind this guy is probably top .01% of all bikers out there.

Now let's imagine that you somehow figured out how to hook up a generator to that efficiently, and let's even assume you found a generator which is 100% efficient, you can't even get a decent hair dryer to to run on 400 Watts. Now back to the real world, when you hook up your generator to your bike you are going to lose efficiency, you will also have a hard time finding a 100% efficient generator. At best your system will be 40-50% efficient, and assuming you put out about 100W you will have 50W of usable power. Not to mention that all this power is less power that is going into your drivetrain.

So to answer your question, no you cannot run a heater off of just pedal energy. Solar energy is even less efficient, the most efficient solar panels will convert 10-15% solar energy into electricity. Even if you covered that canopy in solar panels, you will be lucky to generate 20W of power under the Saharan Sun...

-Ali

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Permalink Reply by heather s on April 6, 2009 at 12:55pm

Not to mention the inefficiency of heating a canopy that is open on two sides. Jill- it seems as though you are trying to make this more complicated than it needs to be. If you are cold when cycling and layers aren't enough, how about trying some of those heat packs you can put in your shoes and gloves? Lights and radios both operate on regular AA or AAA batteries. I admire your attempt to create your own power, but I'm not sure why you want to lug around solar panels and a 12v battery.

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Permalink Reply by koala on April 6, 2009 at 12:58pm

Ali makes a lot of good points. I'd just like to add that there are electric generators available for bikes, these often go under the name of hub dynamo, or something like that. These are typically 3-6 watts, enough to power lights, maybe a radio. But a 6 watt heater isn't much of a heater.

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Permalink Reply by Michael J Blane on April 6, 2009 at 10:02pm

You might look into induction for generating, but like others said, I don't think you'll get enough juice.
Check the lighting method at www.reelight.com.

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Permalink Reply by pistola on April 7, 2009 at 1:18pm

Have you looked into wind generators at all? I know hymini makes portable wind turbines that charges a lithium ion battery that you can use to charge a cellphone or something similiar. Not much power (1W) but you won't lose any power by pedalling to hard either.
http://www.hymini.com/html/FAQ.html#hymini_2

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Permalink Reply by root on April 7, 2009 at 5:47pm

this reminds me of my late 90's attempt to hook up a tv and snes in the back of my buick. never happened

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Permalink Reply by Ali on April 7, 2009 at 6:39pm

That is way too small of a power band to work. But this might be a little more suited to her needs.

Wind Generator

The plus side of using a wind generator such as the one I have above will be the fact that it will charge the batteries when the bike is still as well as in motion, they are designed for marine use so water penetration into the generator won't be an issue. It would look ridiculous to ride around with a wind generator attached to your bike though. And whether you like it or not, any power generation will cause drag, it is just a physical fact. Wind generators will cause aerodynamic drag, pedal, hub, or bottle generators will cause mechanical drag. You cannot generate power without a side affect of drag.

-Ali

P.S.:Eventhough I am giving you ideas this is IMHO is still a stupid idea...Just layer yourself, and attach a battery operated AM/FM radio and be done with it...


pistola said:

Have you looked into wind generators at all? I know hymini makes portable wind turbines that charges a lithium ion battery that you can use to charge a cellphone or something similiar. Not much power (1W) but you won't lose any power by pedalling to hard either.
http://www.hymini.com/html/FAQ.html#hymini_2

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