Sally Kayoni, the shopkeeper, stands on tiptoe to be seen over a counter lined with car batteries, radios and DVD players. Yet the prime retail space on the eye-level shelf behind her is given over to small solar lamps presented in a neat row. They get pride of place because they are among her bestsellers.

“I had so many customers asking for them,” she says. Each month she sells more than 200 of the simple devices, which cost a little over £6 and when charged in direct sunlight will light a small room from dusk to dawn.

The 34-year-old runs one of the busiest shops in Bomet, a fast-growing town of four streets and clanking construction two hours’ drive from Kenya’s world-famous safari destination, the Masai Mara. With its paved roads and electricity, it is typical of east Africa’s new boom towns, servicing a hinterland of small farms that operate off the grid, accessible by dirt roads plied by motorcycle taxis.

Kayoni first started to notice the solar lamps when they were brought to the area in 2012 in a striking canary-yellow van owned by SunnyMoney, a subsidiary of the UK-based charity SolarAid.

They were initially distributed through the area’s schools, where head-teachers were persuaded to pitch the lamps to parents as a way of helping children to do their homework. One year on, a conventional market for the lights has been created and they are sold in shops.

Fewer than 20% of Kenyan homes have access to electricity and are therefore forced to use fossil fuels such as kerosene for lighting. Households that give up the kerosene lamps they used previously can expect to make a saving of roughly £40 a month, which can be spent on school fees, food and other goods. “Previously the money was leaving the community and going to global oil companies [through kerosene sales],” Andrews says. “Now it is going to local businesses.”

The educational impact of thousands of solar lights in once-dark homes can be measured around Bomet. Christopher Sigei, the area education officer, has been doing just that: “In the evening it has been working small miracles.”

Asked about local access to electricity, he smiles and describes it as “zero point something”. The average mark in national exams in the poorest neighbourhood, he points out, has risen from 215 to 233 in the first year since the lights went on sale.

To read more, click here.

Photo credit: Nicole Sobecki