My computer, the toaster, a light bulb… If I have a generator hooked to a bicycle wheel what can I power by cycling?
You can probably power a peak load of about 200 watts or so for a short time, say, about 10-15 seconds before pooping out. Continously, you can probably manage 40-60 watts or so. If you’re in top physical, Lance Armstrong, condition you might be able to double those numbers.
Correction: Make that a peak load of about 400 watts - that’s just for a second or two, max. 200 watts is sustainable for maybe 15-20 minutes, not seconds. I misspoke there, sorry.
In any case, here is a previous thread on this subject.
Hmmm …you’d need 20-40 people cycling at once just to get a regular household level of power. I wonder how much juice a notebook PC + cable modem uses? Also, since the power delivery rate would vary somewhat as you got tired what would you use to keep it from damaging equipment by “browning out” all the time?
Some sort of energy storage device, such as a battery or a capacitor bank, similar to systems used in other fluctuating power generation technologies, like wind power.
A science museum I went to as a kid had a simple no gear bicycle and as a kid I managed to get a TV enough power to be on, and that was a big old tv. I think with gears you can get a pretty decent amount of power.
Kinda. Power is equal to energy divided by time. Gears can increase the amount of deliverable power, but there will be a corresponding decrease in the amount of time you can sustain that level.
A reasonable rider might be able to deliver perhaps 200watts continuously, that will not run much, couple of medium wattage lights, that’s all.
However, you could use it to charge up a bank of batteries, and use that collected energy to run other things.
Your main problem when trying to run an alternator is not actually the electrical output, human beings need to keep within certain body temperature levels, and without the cooling air that free cycling provides, a pedallist will get hot very quickly and sweat heavily, this can bing its own issues, from electrolye losses, to losing traction on the tyres due to copious amounts of sweat, and a greatly increased heart rate.
The fitter you are, the easier it is, but it is pretty much the same as riding an indoor trainer.
For an average person, not wanting to become uncomfortable, I reckon 100watts would be plenty.
I thought the informal power unit for a person is the un-PC term - the manpower.
As I said it is used informally but as a rule of thumb, a person can generate one tenth of a horsepower which is about 55 foot-pounds per second - or about 75 watts. (Incidentally, is a bike generator 100% efficient? Just something else to consider).
Incidentally, is there a generator made specifically for a person to operate manually that could produce 75 watts of power and would produce a regulated 120 volts AC? If nothing else you could power a small lamp, a small television and a radio. Heck, it would be nice to have a small chunk of civilization at your disposal.
(Air conditioners and microwave ovens would be completely out of the equation !!!)