This research examines the impact of energy efficiency on economic growth and environmental sustainability in the top 10 nations with the highest energy efficiency levels between 1990 and 2019. The study uses sophisticated econometric methods, including Westerlund panel co-integration tests, to analyze the relationship between energy intensity, availability, security, and depletion, as well as their effects on carbon dioxide emissions, ecological impact, and economic development. The findings indicate a positive correlation between energy intensity, availability, and security with economic growth, while a decrease in energy availability negatively impacts economic growth and increases carbon dioxide emissions and environmental impact. The research suggests that economies must balance economic and ecological goals by improving energy utilization to achieve sustainable development. The study also highlights the importance of green investments and technological innovation in promoting sustainable economic growth and environmental protection.This research examines the impact of energy efficiency on economic growth and environmental sustainability in the top 10 nations with the highest energy efficiency levels between 1990 and 2019. The study uses sophisticated econometric methods, including Westerlund panel co-integration tests, to analyze the relationship between energy intensity, availability, security, and depletion, as well as their effects on carbon dioxide emissions, ecological impact, and economic development. The findings indicate a positive correlation between energy intensity, availability, and security with economic growth, while a decrease in energy availability negatively impacts economic growth and increases carbon dioxide emissions and environmental impact. The research suggests that economies must balance economic and ecological goals by improving energy utilization to achieve sustainable development. The study also highlights the importance of green investments and technological innovation in promoting sustainable economic growth and environmental protection.