Originally Posted by
ModoVincere
All you need is an automobile alternator, a deep cycle marine battery, a rectifier, and some additional hardware to connect everything up to your trainer....costs...maybe $200.00. Then you could use an LCD TV made for RV's/Boats whose electrical systems are often 12V DC. You could charge the battery while riding the trainer or you could run the TV directly (using the Battery to stablize the output for the TV's electronics).
If you are really strong, you might be able to charge the battery while watching the TV, but I don't think most of could do that.
Basically, an average cyclist could produce about 150 Watts in a steady state for about an hour maybe two....at 14V, this would be about 10.5 amps of electricity.....check the current requirements on the electrics and match everything up, and it should work fine.
I am not sure of using a car alternator. I thought about doing this. First a car alternator is designed to put out current at idle of the engine, Say 800 rpm (at crankshaft) most car altenators I have seen have a much smaller pully then what is on the crankshaft. So I would say the altenator is running twice as fast. (1600 or more) This would mean you would have to be running to very tall bike gear. Consider your "crankshaft" RPM would be 100 (cadence).
Next, I don't know how low of a wattage car altenator is out there, but a small one these days I have seen is 60 AMP @ 12+V. 60X12=720 watts. This would be max of the altenator. But a very large load (big hill) in a very tall gear.
I suppose if you limit its current out put in the 200w range it might be doable, but I don't know if you would get a good output at a slow alternator speed.
Has anyone done this?
Jeff