Solar energy systems have emerged as a viable solution to meet electricity needs in rural areas of Nigeria where access to conventional power is limited. A mixed methods study combining quantitative survey data from 500 randomly selected households with qualitative interviews to explore factors influencing system adoption and long-term viability. The proportion of households adopting solar energy systems was found to be 42%, with significant differences observed between rural and urban settings. Qualitative insights revealed maintenance challenges as a key sustainability issue. While solar energy is increasingly adopted by poor households in northern Nigeria, maintaining these systems over time remains a challenge due to affordability issues. Investment in long-term support services for system upkeep should be prioritised to ensure continued use and reliability of solar installations among the poorest communities. solar energy adoption, cost-effectiveness, sustainability, mixed methods study, Nigeria