[pct-l] Recharging electronic devices while out hiking

[greg mushial]

> Message: 1
> Date: Wed, 27 Oct 2010 10:06:08 -0700
> From: John Abela <pacificcresttrail2011 at gmail.com>
> Subject: Re: [pct-l] Recharging electronic devices while out hiking
> To: pct-l at backcountry.net
> Message-ID:
> <AANLkTi=c5HrnXKRty-UA0DvqRSbaE8vgbcY4htHfbwPS at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> http://www.npowerpeg.com/personalenergy/specs
>
> This page states that it produces 2.5 watts.
>
> That is pretty much half of what most smartphones these days require to
> charge.
>
> My iPhone pulls a constant 5.0 watts during recharging (as does a kindle)
>
You need to be careful in how you read the website. If you do the physics, 
it appears that the generator generates something in the 30-50ma range, 
which is stored in the 1000mAh battery - which is in fact what is used to 
charge your device. For it to "generate 2.5 watts"... you wouldn't want to 
carry the beast. Personally I've gone a similar route, but with solar, ie, 
use small flexible 2oz waterproof panels sewn to the back of my pack (seems 
I'm mostly a NoBo hiker), which charge batteries, which are then used to 
charge a phone and flashlights. The principle is the same: gather a little 
charge here, a little there, and then pretend to be a USB port when it comes 
to recharging devices which are used to/expect such. The next step in this 
experimentation is to learn which phones will accept a trickle charge, 
thereby eliminating the need for the intermediate storage battery, and the 
associated weight. Some phones expect and will only work with a 500ma 
capable "USB" port - one Nokia (N5230) seems to be happy down to the 30ma 
range...  but I have a lot more work to do on this (time permitting). [one 
discovery I've made is: at 10-15ma, 9v NiMH batteries can't be overcharged 
(cooked/destroyed), ie, one can leave them connected all day, not worry 
about charging/autodisconnect electronics, and simply unplug them and use 
them at night - which is sweet, ie, less electronics involved, less to fail, 
and less weight, though only an oz or two.]
TheDuck