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solar bud

Commercial pedal generator

Probably best to make your own if you can, but if not I found this commercial pedal generator in the States:

http://www.econvergence.net/Merch...t_Code=PAWA-1&Category_Code=5

You just slot your bike in and away you go . . .
adam2

Human powered generators can certainly be useful for small scale, short term or emergency power needs.
Most people though, until they have tried it, have a very inflated idea of how much power can be produced.
I recently asked a number of people* "what is the value, per hour, at normal retail prices, of the electricity that a person could generate by pedalling"
The answers ranged from 50 pence up to several pounds.
The answer is one penny! possibly two pence if you are very fit!

I recently produced 150 watts on a cycle generator VERY briefly, I could not sustain more than 50 watts. Someone fitter than me would produce more, but I doubt that many could sustain much more than 100 watts for any time.

*All members of a very green group
Blue Peter

adam2 wrote:
I recently produced 150 watts on a cycle generator VERY briefly, I could not sustain more than 50 watts. Someone fitter than me would produce more, but I doubt that many could sustain much more than 100 watts for any time.

*All members of a very green group


Is the wattage measured differently than on a normal exercise bike? Judging by the ones at our gym, it shouldn't be too difficult to generate 150 watts for an extended period of time,


Peter.
adam2

I suspect that it may be measured differently, although I am not familiar with excerise bikes they probably measure watts of mechanical effort,  not watts of electric power.
If the generator was 100% efficient then these two figures would be the same.
Since in practice the generator is not 100% efficient, the watts of electricity will be less than the mechanical input, perhaps by as much as 50%

It is also possible that the watts display on an excerise bike is optimistic in order to flatter the paying customer.

Alternativly you may be much fitter than the average, I would consider 150 watts achievable by an athlete, but not by mr avaerage (other than very briefly)
Blue Peter

adam2 wrote:
I suspect that it may be measured differently, although I am not familiar with excerise bikes they probably measure watts of mechanical effort,  not watts of electric power.
If the generator was 100% efficient then these two figures would be the same.
Since in practice the generator is not 100% efficient, the watts of electricity will be less than the mechanical input, perhaps by as much as 50%

It is also possible that the watts display on an excerise bike is optimistic in order to flatter the paying customer.

Alternativly you may be much fitter than the average, I would consider 150 watts achievable by an athlete, but not by mr avaerage (other than very briefly)


50% efficiency would make sense. I reckon, when on top form, I could do about 300W for 15 minutes, which would translate nicely to your 150W electrical,


Peter.
Eternal Sunshine

Just think if all the exercise bikes in the land were linked up to generators somehow tho - that may produce a decent amount of energy.  Laughing

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