By CATE DOTY


Start-up companies around the world are looking at Africa - where 74 percent of the population lives without electricity - as a test market for new, off-thegrid lighting technologies.

Many of these efforts involve wind or solar power. But one group in Cambridge, Massachusetts, is working to develop fuel cells made from the bacteria that occur in soil or waste.

“You can just literally make energy from dirt,’’said Aviva Presser, a graduate student at the Harvard School of Engineering and Applied Sciences.“And there’s a lot of dirt in Africa.’’

Ms.Presser is one of the founders of Lebone Solutions, which is being financed by a $200,000 World Bank grant and private investments. Lebone’s idea is a microbial fuel cell, a battery that makes a small amount of energy out of materials like manure, graphite cloth and soil, which are common to African households.

But Lebone - which means“light stick’’in the Sotho language - does not just want to make the batteries and sell them to African consumers. The group hopes that eventually each household will be able to build a battery at a cost of no more than $15.

“Africans are very, very creative,’’said Hugo Van Vuuren, a Lebone founder.“It’s very entrepreneurial, just not in the way we traditionally define entrepreneurial.’’

Mr.Van Vuuren, who is from Pretoria, South Africa, and who graduated from Harvard last year with a degree in economics, likened the simplicity of the battery to“the potato experiment that most of us did in high school class,’’a two-step reaction that produces a simple charge.

But the bacteria in a microbial fuel cell produce electrons while doing what they naturally are supposed to do: metabolize organic waste, like dead leaves or grass or compost, for energy. The electrons then stick to an electrode, like a piece of graphite, and the chemical reaction that follows creates a small charge sufficient to power a small lamp or cellphone.

“It can be made by people with minimal training,’’Ms.Presser said.“It doesn’t take a massive investment.’’

The founders of Lebone took the technology to Leguruki, a village in Tanzania, to see how the batteries work in households. For three hours each night, six families used batteries made of manure, graphite cloth and buckets, and a copper wire to conduct the current to a circuit board.

“People walk an hour or more a day to the local high schools to get their phones charged for two or three days,’’he said, noting that the phones were sources of light as well as communication devices.
The batteries are also used to power radios, Mr.Van Vuuren said, as important a medium of communication in Africa as the cellphone.

“Ideally, they would like to have a refrigerator,’’Mr.Van Vuuren said.“But right now, their key need is a cellphone.’’