Office Depot has decided to exploit the growing market of the solar powered backpacks and is launching a new line of solar charging bags, produced by Volatic Systems. The bags feature three lightweight, waterproof solar panels, generating up to four watts of electric power. The bags can be used to charge Blackberrys, MP3 players, digital cameras, two-way radios, PDAs, and nearly all brands of cell phones. Unfortunately, these bags will not be able to charge your laptop any time soon, due to their power limitations. 

Each bag comes with a lithium-ion battery pack with a 4400 mAh capacity. The battery stores any surplus power generated by the solar panels to be used when solar charging is not available. Another way to charge the battery pack is to use an AC travel charger or car charger (both included). The bag itself does not feel stiff or restrictive, since the solar panels are integrated into the back pocket of the bag. Moreover, there is no need to unpack and setup the panels: they are built into the back of the bag in a way that allows them to articulate. In order to make them more durable, the panels were built on a strong but lightweight aluminum plastic composite. According to Office Depot, the solar charge of a typical cell phone is 4-6 hours in direct sunlight. 

Besides harnessing solar power, the Volatic Systems bags were produced mostly from recycled plastic soda bottles, making the bags environmentally friendly in more than one aspect. Currently, Office Depot is marketing two similar models of the solar charging bag. The first model is the Voltaic Converter, which can be used as a standalone daypack and can be easily attach to another bag using the included buckles. The second model is the Voltaic Messenger, which is aimed at the professional businessperson. Both models have padding and a nylon mesh backing for better air flow. Furthermore, both bags come with a USB adapter and at least 10 other standard adapters for common devices. A one year limited warranty is guaranteed. The bags also include a lined MP3/sunglasses pouch and high-density padding in the shoulder straps and back panel. 

Although the bags are not suited for charging laptops, they have a fully padded compartment which can protect a notebook computer. The PC compartment is a nice addition, but might  mislead potential buyers. 

TFOT has covered two other solar energy chargers: Philips' Power4Life series and the Freeloader. Other related TFOT articles include a story on new nanowire batteries, which use silicon nanowires to produce ten times the amount of electricity of a comparable Li-ion battery, and the coverage of the Air Tree, a structure that generates clean renewable energy, produces oxygen, and serves as a unique social gathering place. 

Office Depot is selling the bags  at $179.99 to $219.99. For more information, see the specification on Office Depot’s website or read about the solar charging technology on Volatic Systems' website.