Renewable Energy, Economic Policy Uncertainty and Climate Policy Uncertainty: New Evidence for Environmental Kuznets Curve from Emerging and Developed Countries

Recent events, such as the financial crisis, oil price shocks or fluctuations, Brexit, the US–China trade war, the COVID-19 pandemic, the Russia–Ukraine conflict and the subsequent energy crisis, have surged global economic policy uncertainty. As climate change has recently been more pronounced around the globe, discussions about climate policies and related uncertainties have also become a major concern. This study investigates the role of economic policy uncertainty (EPU) and climate policy uncertainty (CPU) on climate change (environmental degradation) for selected emerging and developed economies, expanding the IPAT framework and merging it with the Environmental Kuznets Curve (EKC) hypothesis. The IPAT framework examines the impact (I) of population (P), affluence (A), and technology (T) on the environment, whereas the EKC hypothesis proposes an inverted U-shaped curve between affluence and environmental degradation. Two models were created and tested for emerging and developed countries, namely Model 1 with EPU and Model 2 with CPU. A Pooled Mean Group (PMG) estimator is employed to investigate the interrelation between carbon dioxide (CO₂) emissions and selected variables; namely the real Gross Domestic Product (GDP) per capita, squared real GDP per capita, renewable share in consumption, the EPU, the CPU and population. Test results indicate that the EKC hypothesis is verified only in Model 1 and for emerging countries, whereas population escalates climate change in both country groups. Furthermore, in line with the consumption effect theorized earlier in the literature, EPU is negatively related to carbon emissions in emerging countries. Thus, the EPU leads to a decrease in the use of energy and pollution-intensive commodities and mitigates climate change in EMEs. Compatible with our ex-ante expectations, renewable energy consumption alleviates climate change in both country groups in the short term. In Model 2, with CPU, we find no evidence supporting the EKC hypothesis for any country groups. However, we reaffirm that renewable energy consumption decreases CO₂ emissions in developed countries, which is in support of the argument that energy transition holds the key to tackling climate change. Finally, CPU is associated with a decrease in CO₂ emissions in emerging countries in the short term, potentially leading to a reduction in overall economic activity and alleviating climate change. This might also be attributable to the fact that the decisions of economic agents substantially rely on current and future policy (both economic and climate) expectations. Overall, verifying the EKC hypothesis for emerging countries in Model 1, we might argue that there is good potential for emerging countries to save money and time on environmental costs via the adoption of clean technologies and related policies. Last but not least, on a global scale, energy transition with better utilization of renewable sources holds the key to tackling climate change and reducing emissions.