But first, some background, because this is fascinating stuff. The typical household in rural Africa is “off the grid.” With no electricity, such households spend a significant fraction of their income on kerosene for lamps. Yet for about $20, they can buy a solar light, which provides a superior source of light and charges their cell phones. (Yes, cell phone use is common, even in rural households with no electricity; they simply walk to the nearest town and pay to charge their phones.) Given that the light pays for itself in about 6 weeks and lasts for about 3 years, purchasing one seems like a no-brainer. Yet few households have done so. These intrepid economists are trying to figure out why, and want to see whether the barriers to adoption can be overcome in a profitable way. In order to do so, they are running controlled experiments in rural Ugandan villages using various combinations of incentives and financing arrangements.