[aprssig] Re: now, 1.5 Lptops Per Child : power options?
Mark A. Lewis
mark at siliconjunkie.net
Mon Dec 31 18:46:47 EST 2007
Remember, you are also using a VERY short lever. If you were to replace
the crank with one that was say, 3 feet long you wouldn't even notice
the load. Add a flywheel with some mass and you could keep it running
with a little creative gearing and a modest power source like wind or
water. Lots of alternative energy folks are using home brew contraptions
in streams with car alternators to run bunches more than a laptop.
From: aprssig-bounces at lists.tapr.org
[mailto:aprssig-bounces at lists.tapr.org] On Behalf Of Scott Miller
Sent: Monday, December 31, 2007 6:40 PM
To: TAPR APRS Mailing List
Subject: Re: [aprssig] Re: now, 1.5 Lptops Per Child : power options?
> One thing you forgot .. when you are generating electricity with a
> 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
> 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
> 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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