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How Solar-powered Backpacks Work


Solar-powered Backpack Applications
The Voltaic Generator has enough power to charge a laptop.
The Voltaic Generator has enough power to charge a laptop.
Image courtesy of Voltaic Systems

If we have solar technology and we know that the modern human is wired and always on the go, it seems like a no-brainer to bring the power of the sun with you. Some clever backpack manufacturers have done just that. Solar-powered backpacks have small solar panels attached to the outside of the pack so you can harness the sun's rays to charge your cell phone, PDA or MP3 player. The panels are lightweight, waterproof and can produce up to four watts of power. This means that just one hour of direct sunlight can produce enough energy to power a cell phone for about an hour and a half.

The key to the solar backpack is the fact that it has a lithium-ion battery pack inside to store this energy. One hour of sunlight might charge your phone for a short time, but a full 10-hour charge provides up to 55 hours of stored energy. For those cloudy days, the packs also have an AC adapter that allows you to charge the battery using your car's power. The packs come with a variety of cell phone adapters and a USB plug for your MP3 player.

There are several companies manufacturing solar backpacks and they range in price from $75 to $250. The less expensive models generally only have a single panel and, as a result, less overall capacity. One company has even introduced a more robust version in the form of an over-the-shoulder bag that can generate a whopping 15 watts of energy -- enough juice to charge your laptop. That kind of versatility comes with a heftier price tag. You can plan on spending $500 for anytime, anywhere laptop power.

For more information on solar-powered backpacks, solar-powered backpack applications and other travel gadgets visit the links on the next page.