Closing the digital divide with solar Wi-Fi

Two colleagues develop Wi-Fi technology designed to work where sources of electricity are unreliable. Photos: Green Wi-Fi

Bruce Baikie and Marc Pomerleau are putting an earth-friendly spin on wireless networks.

Their nonprofit organization, Green Wi-Fi, is trying to bring Internet access to schools in developing countries via cheap, solar-powered Wi-Fi networks. The newly formed venture came out of a wish to which many parents can relate: showing their kids there's more to life than the daily grind of corporate politics.

"When you have children, you start really thinking about what you want to tell them that you do with your life," Pomerleau said.

Pomerleau, who until recently was a member of the marketing team for Sun's identity management products, quit his day job to focus on Green Wi-Fi, the nonprofit he started with Baikie, who kept his own day job at Sun.

The technical concept behind the Green Wi-Fi network is fairly simple. Each node in the network consists of a battery-powered router and a solar panel to charge the battery. The nodes are mounted on rooftops, and the network's Wi-Fi signals are transferred over a grid using a wireless network standard known as 802.11b/g.

The first seed money has arrived, enough to produce and test prototype nodes. It came from the One Laptop Per Child initiative (OLPC), which aims to construct a $100 laptop to be distributed to children in developing countries. OLPC showed immediate interest in the Wi-Fi initiative, Pomerleau said.

"We've heard that the strongest criticism they get when they evangelize their laptop is 'What do you do about the network?' If you have a computer but no Internet, you can play games and do spreadsheets, but accessing the world's information is really where the value is."

Green Wi-Fi

The two men decided that Wi-Fi technology would make the most sense, since it is standardized, relatively inexpensive and simple to deploy. The trick to operating a Wi-Fi system in many developing countries is to find a consistent source of electrical power. But while billions of people don't have reliable electricity, most of the developing world doesn't lack sunlight.

One of Baikie and Pomerleau's main challenges was to develop a solar-powered system that would function under variable weather conditions. A commercial solar-based system can run for as long as a week without incoming light. A monsoon season in India or a rainy season in the tropics, however, can last for a month.

Elegant degradation
The developed-world response might be to get a larger battery and a bigger solar panel to charge it, but that increases the cost. Baikie and Pomerleau set their cost ceiling at $200 dollars per node and went for a solution they call "elegant degradation."

"What we bring to the table is an intelligent charge-controller. We put the router on a diet," Pomerleau said. The controller sits between the battery and the router and regulates power to the router depending on the charge level of the battery and the amount of incoming sunlight.

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