Pay As You Go Solar Energy Finds Success in Africa Scientific American Nov 23 2013

Selling solar energy on an installment plan is an affordable alternative to kerosene fuel.

A creative way of selling solar energy is gaining traction in sub-Saharan Africa: customers can pay as they go.

Only one in six rural inhabitants in sub-Saharan Africa has access to electricity. For households living off the grid, kerosene lamps are the primary lighting source—an expensive technology that is also unsafe, because kerosene is flammable as well as poisonous when inhaled or ingested. . . . Across the U.S. and U.K. electricity from a utility costs between 10 to 15 cents per kilowatt-hour (kWh). A villager in rural Kenya or Rwanda, however, pays an equivalent cost of $8 per kWh for kerosene lighting. . . .

http://www.scientificamerican.com/article.cfm?id=pay-as-you-go-solar-energy