Asymmetric impacts of nuclear energy on ecological sustainability: Evidence from the load capacity curve in major nuclear economies

Abstract

This study examines the asymmetric effects of nuclear energy consumption on ecological sustainability in major nuclear‐powered economies. It investigates whether increases and decreases in nuclear energy consumption have different impacts on environmental quality, measured by carbon dioxide (CO ₂ ) emissions, ecological footprint (EF), and load capacity factor (LCF), while also testing the Environmental Kuznets Curve (EKC) and Load Capacity Curve (LCC) hypotheses. The empirical framework initially considers three environmental indicators: CO ₂ emissions, EF, and LCF, while long‐run asymmetric effects are estimated for the LCF and EF models, for which cointegration is established. The analysis uses panel data for 27 countries over 1993–2022, representing 97.4% of global nuclear energy consumption. A panel ARDL framework with pooled mean group (PMG) and mean group (MG) estimators is employed, and nuclear energy consumption is decomposed into positive and negative shocks to capture asymmetric effects. The results reveal asymmetries in the LCF and EF models. Positive shocks to nuclear energy consumption enhance ecological sustainability by increasing the LCF, whereas negative shocks raise EF. Moreover, the environmental benefits of positive nuclear energy shocks are stronger than the adverse effects of negative shocks. The findings confirm the LCC hypothesis and support the EKC hypothesis for the EF model, while no long‐run cointegration is established for the CO ₂ model. These results highlight the practical importance of expanding and maintaining nuclear generation, particularly where it substitutes for fossil‐fuel‐based electricity. Carefully governed nuclear energy policies can therefore support ecological sustainability and advance progress toward Sustainable Development Goals 7 and 13.