Nigeria faces an urgent energy challenge marked by chronic electricity shortages, dependence on fossil fuels, and worsening environmental degradation. This study examines the economic and environmental benefits of transitioning to renewable energy in Nigeria, adopting a mixed-methods approach that combines a systematic literature review, policy analysis, and synthesis of empirical case studies. Findings reveal that Nigeria possesses vast potential for solar, wind, biomass, and hydropower, capable of transforming its energy landscape. Economically, the adoption of renewable energy can generate employment, stimulate industrial growth, expand rural electrification, attract investment, and stabilize public finances by reducing vulnerability to global oil price shocks. Environmentally, it can reduce greenhouse gas emissions, improve air quality, conserve biodiversity, promote sustainable waste management, and enhance resilience to climate variability. Case studies demonstrate the effectiveness of decentralized solar mini-grids, biomass utilization, and hybrid systems in meeting local energy needs; however, persistent barriers, including weak policy enforcement, financing gaps, and infrastructural limitations remain. The study concludes that a comprehensive framework is required, built on policy alignment, financing innovation, institutional strengthening, infrastructure development, and social inclusion. Renewable energy transition thus represents not only a climate responsibility but also a strategic pathway for Nigeria’s sustainable economic and environmental future.