'Modern MacGyvers' Build Dirt-Batteries, Bionic Rice

June 5, 2010— -- Resourceful as he was, it's doubtful that even the MacGyver of television fame would know how to make a battery powered by dirt.

Thursday night, at a World Science Festival presentation in New York, Hugo Van Vuuren, a Fellow at The Harvard School of Engineering and Applied Sciences, explained how he and his partners, who met as undergraduates at Harvard, figured out how to harvest power from some of the most abundant stuff on Earth: soil.

During an event featuring "modern MacGyvers" -- inventors, biologists and engineers innovating for the developing world -- Van Vuuren described how the microbial reactions in a bucket of mud could be used to provide electricity to approximately 500 million people in Africa who don't have access to it.

Van Vuuren said that so-called "microbial fuel cells" are based on science that was discovered about 80 years ago, but until now it was considered too weak to use.

"It's just a technology, a science, that creates very small amounts of electricity -- a trickle charge -- that up till now has not been useful for us because we needed to power refrigerators and cars and big things," he said. "But now, we as a people, all of a sudden, we realize that there are 4 billion other people who live on less than $5 a day and they are a market."

Building on research into microbial fuel cells, Van Vuuren said he and his partners created a battery that derives power from the energy created as soil microbes break down organic matter. As long as the soil stays moist enough, he said the soil can continue to generate energy for eight to 12 months (in the lab).

The team created a start-up called Lebone (which means light, lamp or candle in Southern Africa's Northern Sotho language), and in 2009 they won the Popular Mechanics Breakthrough Award for their battery design.

It's a prototype now, but Lebone is working to scale production of the battery to move the cost to about $10 per battery, down from about $30 or $40, so that it can start distributing the battery in sub-Saharan Africa.

Van Vuuren wasn't the only "modern MacGyver" recognized on Thursday. Meet three others.