Human powered generator...motor/coil?

Question

I asked a while ago about this, but I there was still some confusion in my mind. My ultimate goal is to use power electric heating coil from human powered bike. I was wondering, I will I be able to create enough power to power the coil?

Here's what I have so far: I took the motor out from an old fan, and I was thinking about directly connecting that to the bike. My question is would that work? If so, about how much power will I be able to get out of it? Am I going to need anything like an inverter? or can I just connect to the two end terminals to the coil, and that would work? Also, am I going to need a diode? Basically, what I am trying to ask is how would I put everything together? I have bits of info, just need to figure everything out.

Also, as for the coil, how does the wattage rating work? I am thinking of using maybe like a teapot coil..

Thanks for all your help in advance!!

Answer 1

Another answer is correct, you are unlikely to be able to generate more than 200 watts for any length of time. Most small heating appliances are rated from about 600 to 2400 watts. If an electric kettle rated at 2000 watts takes 4 minutes to bring a quantity of tap water to the boil then a 200 watt input would take 40 minutes to do the same, barring losses of heat. With losses you could be looking at an hour or more

A fan motor may generate some power but it you will have to energise the rotor or stator coils. This might only need a little rewiring. Best thing is to weld up a connection to the chain or rear wheel and find out what happens. You are unlikely to get a mains voltage output though.

Another possibility is a DC generator from an old car. These were generally rated at somewhere between 20 and 50 watts and produced about 8 or 14 volts. Most cars since about 1960 have used alternators so to get DC you will need to go back quite a way.

In 1928 -29 Alf Traeger in Australia developed a pedal operated generator to power small radio transmitters and receivers.

Search "pedal radio" for more details.

Answer 2

The power will not be constant because of how people use bicycle (sometimes they stop, etc...). Of course, the faster the motor turns, the more power you get out. Technically, depending on the heating coil, the more cycling the hotter the coil.

As for the other questions, that's a little out of my range, sorry :P

Good luck with your project though!

Answer 3

Unless you're a professional-level cyclist, you're unlikely to generate more than about 200 watts for any length of time.