Renewable Energy, Economic Growth, and CO₂ Emissions: A Comparison of the United States and China (1990–2024)

This paper compares economic growth, carbon dioxide (CO₂) emissions, and renewable energy use in the United States and China—the world's two largest economies and largest greenhouse gas emitters—over the period 1990 to 2024. Prepared as a capstone project for the final year of secondary school, the study draws on freely available data from the World Bank, Our World in Data, and the European Commission's EDGAR database. Percentage-change calculations, trend analysis, Pearson correlation coefficients, and simple linear regression were carried out in Microsoft Excel. The results show that the United States has cut its absolute CO₂ emissions by roughly 30 percent since their 2005 peak, while China's emissions have nearly tripled since 1990. A strong negative relationship is observed between economic growth and emissions in the United States (r = –0.78), whereas the same relationship in China is strongly positive (r = +0.96). The regression models suggest that emissions fall as the U.S. economy expands, while China has not yet reached that stage of development. In both countries, however, a rising share of renewable energy is associated with a decline in emissions.