Nairobi, Sept. 13 -- In Kenya, the energy transition arrives on a phone screen as a 20-digit number. That number is what a growing number of households see when they buy prepaid electricity. And as the country moves toward another election in August 2027, that number could become a more powerful measure of the government's energy record than any statistic about renewable power.

Kenya gets more than 90 percent of its electricity from renewable sources, led by geothermal, hydro and wind. It is one of the world's cleaner electricity systems. But clean does not necessarily mean cheap. For the consumer, the question is much simpler: How many units did their money buy, and how long did they last? That is where Kenya's energy success story beco...