Originally Posted by saunders1313
Has anyone heard of any ideas on how to convert a stationary bike to be able to produce electricity to feed into the grid? I understand the concept of how solar power is fed into the grid, put what about a bike? I know I wouldn't produce too much energy, but some is better than none. I'm going to use the bike anyway might as well get something out of it if I can.
I ride a stationary bike whenever weather won't allow me to ride the real deal. I thought of configuring the bike to generate power to watch TV while pedaling. So I did math and finally concluded that it would never pay for itself. The electrical power that I could produce would be on the order of a penny a day, or not even that much.
The place that a generator on a stationary bike makes sense is if you have no electrical power, i.e. in your cabin in the hills. Or if you want to power a TV or stereo and use them as your incentive to do the exercise.
Consider that 1 horse power is 740 watts (or there abouts). That is 3/4 of a KW. If you can pedal at a rate of 1 HP for 1 hr. (you cannot) you could produce maybe 7 cents worth of electricity (@ $.10/KWH) if your machine were 100% efficient (it would not be).
Realistically you might produce 1/4 that much power if you are in really good shape. Your equipment and the transfer from pedal to electricity and then through the circuitry required to change it to 60Hz AC is probably gonna be 50% efficient at best. You are now looking at 1/8 of 7 cents for an hour of very hard pedaling. Not even a penny an hour.
Even if your equipment cost you a mere $100 it would take 10,000 hours of pedaling to break even. In that many hours your equipment would probably need replacement. You would never break even. In fact, my guess is that it would be a considerable net loss.