Unlike developed nations, many of the places where this technology was designed to be deployed lack electricity, so the Green Wi-Fi project designed a self-contained unit consisting of a solar panel, charge controller and battery for power, and a modified Linksys WRT54GL wireless router with a high gain external omni-directional antenna for the internet access part. These boxes form the nodes of a self-healing mesh network. Connect one or more of them to the internet somehow (often via a cellular modem) and you can share that connection across the entire mesh. Since the boxes need no external power, they can be placed on rooftops anywhere to build up the mesh.

Got Wi-Fi, Now What?
Having a solar powered Wi-Fi mesh alone doesn’t get you much, so what else is needed to make this useful? Well, the most obvious thing that is needed next is computers, and the OLPC project’s XO laptop makes a perfect device for use with the mesh Wi-Fi network. The team at Green Wi-Fi have also developed solar charging solutions for these little laptops, allowing a school to have a collection of them which can be charged using a panel mounted on the roof of the school building.

Bruce Baikie, Green Wi-Fi’s CEO, just returned from a trip to Senegal along with a group of high school volunteers from San Francisco, where they delivered 25 OLPC laptops to the village school, and installed a 60W solar charging station for them too. The US high school students also trained the village’s teachers how to use and maintain the new laptops, as well as helping to repair school rooms, desks, the village health clinic, bathrooms, roofs, and anything else they could help with. Later this year Bruce will be returning to install a Wi-Fi mesh (they currently have just a single network connection provided by a very power-hungry, and somewhat unreliable, CDMA modem).

Photos from Senegal

[Senegal photos with thanks from Bruce Baikie @ Green Wi-Fi.]

In PolyFuel’s prototype, the power supply features a detachable fuel cartridge – about the size of a deck of cards – that can be swapped out while the computer continues to run. Long-distance travelers, or others needing continuous, unconnected, easily portable power for their notebooks, would simply carry spare cartridges in their pocket or purse – a someday common practice that has already been approved for commercial aircraft by the various regulatory bodies around the world.

What are the Advantages?

From an environmental perspective, a methanol fuel cell is a much better technology than the lithium ion batteries we use today. Methanol is a renewable fuel, and the cells can be made from biodegradable or easily recycled materials. While the batteries in today’s laptops can be recycled, it is a much more costly process.

But, as with many things green, the methanol fuel cell has other advantages over the batteries it replaces: with current technology, they last three times longer than a lithium ion battery; in the future that may increase to as much as 10 times. They are also much lighter than batteries, so the traveling worker now has a power source that will last for a long haul flight, and make the hand luggage lighter (that alone is a big deal if you travel regularly with a laptop!). Since they’re also refillable rather than rechargeable, should it run out mid flight you just need to swap the methanol cartridge to keep working.

Disadvantages?

Well, like any new technology there are likely to be some issues for the early adopters. Getting through security checks at the airport with a new feature like this might take some patience (ask the folks with the solid state drive version of the Mac Air).

Being away from home and running out of methanol might be a problem too. Plugging in for a recharge is usually possible today where ever you are likely to find yourself with a laptop, but buying replacement methanol cartridges might be harder, especially when you get in at midnight after a delayed flight.

As this technology becomes more common though, these problems will go away and we’ll all be enjoying laptops that last for days on a lightweight power source.

[Via GreenUpgrader]