Solar photovoltaic (PV) products are touted as a leading solution to long-term electrification and development problems in rural parts of Sub-Saharan Africa. Yet there is little available data on the interactions between solar products and other household energy sources (which solar PVs are often assumed to simply displace) or the extent to which actual use patterns match up with the uses presumed by manufacturers and development agencies. This paper probes those questions through a survey that tracked approximately 500 early adopters of solar home systems in two off-grid markets in Africa. We find that these products were associated with large reductions in the use of kerosene and the charging of mobile phones outside the home. To a lesser extent, the use of small disposable batteries also decreased. However, solar home systems were, for the most part, not used to power radios, TVs, or flashlights. We also did not observe adopter households using these solar products to support income-generating activities.