This study analyzes the economic and environmental performance of renewable energy using national case studies and both linear and power regression models. It explores how renewable energy impacts greenhouse gas emissions in relation to GDP per capita, fossil fuel and renewable energy use, R&D expenditure, industrial value added, and urbanization. The findings show that renewable energy promotes economic growth by creating jobs, driving innovation, and improving energy security while also reducing emissions. However, challenges such as technology limits, material scarcity, financial barriers, and public perception remain. The study emphasizes the need for strong political support, continuous innovation, effective financing, public engagement, and circular economy practices to overcome these issues. Ultimately, the research aims to inform stakeholders and support efforts toward a sustainable and effective global energy transition.