The idea of using solar power for off the grid electricity is not new. But the Econet Home Power Station, being developed for the African market, tells us a lot about the integration of cellular networks, payments, and the electrical grid in the developing world. The device’s developer is Econet Wireless, a mobile carrier with operations from Botswana to Burundi, and the solar generator contains a SIM card to allow customers to pay wirelessly for the power generated. Mobile payments have had far greater success in Africa because people have cellphones, but don’t have credit cards or laptops. Paying for off the grid power wirelessly is an important innovation that makes it easy for companies to charge for deploying renewable energy to places like Africa, where 70 percent of people don’t have electricity.