Are solar mobile lanterns really mobile? What sensor data reveals about women's lantern use in refugee camps

Solar mobile lanterns are among the most widely deployed energy interventions by humanitarian organisations in refugee camps. Recent UNHCR guidelines advocate multipurpose lanterns that provide both lighting and phone charging, reflecting ongoing design efforts by humanitarian actors and manufacturers to enhance night time mobility and safety. This study examines how solar lanterns are used for night-time mobility in a protracted refugee camp, using embedded sensor monitoring, alongside household survey data analysed through a gender lens. Distributed in Rwanda's Nyabiheke refugee camp, we find that lanterns are predominantly used as stationary household lights, with the median lantern journey involving only 17 steps and lasting 1.72 min. These findings show that night-time mobility in refugee camps is shaped less by individual movement than by household-level energy practices and constraints. This disconnect between how solar lanterns are justified in humanitarian energy policy and how they function in practice, highlights the value of sensor-based monitoring for policy design, procurement, and evaluation.