There are 3 solar panels in the back to charge the main internal Li Ion battery pack.  The battery can also be charged via AC/car.  The power is distributed by wires in hidden channels to the various pouches and pockets. 

I'm going t have to check these guys out next time I'm down in NYC!

Power...you can't ever have enough of it, especially for running your gear! 

The folks at Voltaic have created a pack not just for hauling around all that gear, but also to help keep it going.

This version is not strong enough to recharge a laptop, but it comes with all the adapters you need to keep the other gadgets juiced up.

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