Several studies have addressed the impact of renewable energy and economic growth on environmental quality. This study adds to the existing literature by estimating their quadratic role (non-linear impact) on the environment within STIRPAT perspective. The analyses are based on data for the panel of Asian-five countries of high population, covering the period of 1983-2019. The aim is an identification of the factors that had contributed to regional’s environmental quality or deterioration. Two models are used; at first quadratic term was added for GDP per capita within the STIRPAT perspective and then the quadratic term for renewable energy. The study's findings revealed that factors including urbanisation, per capita GDP, and the use of renewable & non-renewable energy all had an impact on CO₂ emissions. The urbanization and renewable energy are influencing factors with nominal effects. In contrast, the use of non-renewable energy and GDP per capita was found to be the main source of CO₂ emissions in the region. The results also revealed that the square term of GDP per capita and renewable energy significantly reduces CO₂ emissions.