Solar backpack (Solar charger)

[Al Johnson]

The panel is too small to generate a reasonable amount of power, even if you 
were by some chance to spend all your walking/cycling time in direct sunlight, 
with your back to the sun, leaning forward to keep the panel at right angles 
to the sun. You can get flexible fold-up panels that could be strapped to the 
outside of a backpack or paniers, but they work much better when you're 
stationary and they can be pointed at the sun. For a worthwhile power output 
they aren't cheap.

If you want something effective for emergencies or extended periods away from 
power a mechanical device is probably more effective. For cycling a good 
dynamo will provide more, and more reliable, power than any bike-mounted solar 
panel. Other than that there are some good quality hand cranked generators 
available, along with a lot of bad ones. There are even a few devices that 
will take energy from irregular movement, a bit like a self-winding watch.

On Thursday 21 May 2009, Daniel.Li wrote:
> Dear All,
>
> Solar backpack absorbs solar energy and turns it into electric energy
> storing in storage battery. It can charge different specification mobile
> phones through corresponding connectors.
>
> I'm really interested in this. And I think solar backpack is much more
> suitable for emergency situation when there is no electricity
> outdoors.This product is easy to operate ,safe to use ,convenient to
> take and fashionable.
>
> Solar backpack is an ideal product for living and traveling. It's much
> more convenient than solar charger, as I don't wanna hold solar charge
> when I'm biking or mountain climbing :)
>
> What do u think? Any idea or comment on this?
>
>
> http://jdhysm.cn.alibaba.com/athena/offerdetail/sale/jdhysm-1037354-1609592
>15.html