[aprssig] Re: now, 1.5 Lptops Per Child : power options?

Scott Miller scott at opentrac.org
Mon Dec 31 18:40:13 EST 2007

> One thing you forgot .. when you are generating electricity with a crank 
> generator .. you are doing *work*.

Yeah, I learned that as a kid, with an old field telephone dynamo, a 
knife switch, and some light bulbs.  You can crank like crazy until 
someone closes the circuit, and you'd just about break your arm if you 
were going fast enough.

> My point is that a windmill or anemometer needs to overcome this 
> resistance to generate electricity .. and it is a considerable amount of 
> resistance believe me. Unless your windmill or anemometer has 15 or 20 
> foot arms .. or you plan on waiting for a hurricane .. I don't think it 
> will work.

It doesn't scale down to small sizes well, you're right.  I was hoping 
it'd be feasible for low-power devices, even if it wasn't very 
efficient, but it's not looking good.


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