How does energy trilemma eradication reduce carbon emissions? The role of dual environmental regulation for China

Realizing carbon neutrality entails a well-established secure, equitable, and sustainable energy system; the trade-offs among the above three aspects constitute the energy trilemma (ET). To this end, by using the data of 30 provinces in China during the period 2000–2019, we examine the direct and heterogeneous impact of the ET on CO2. We also creatively investigate the role of dual environmental regulation (DER) in mitigating CO2, as well as its moderation and threshold effects on the ET-CO2 nexus. We thus present the following findings: (1) the ET exerts an aggravating impact on the phenomenon of CO2, and energy inequity shows the most prominent positive impact on CO2; (2) developing DER effectively accelerates the process of CO2 alleviation; (3) DER significantly moderates the nexus between the ET and CO2 by reducing the adverse effects of the ET on the environment, and formal environmental regulation (FER) plays a more effective role than informal environmental regulation (IER) in mitigating the positive ET-CO2 nexus; and (4) DER shows a significant threshold effect, and when the intensity of DER is high, the negative impact of the ET on CO2 can be alleviated to a large extent. Based on these findings, we propose several policy implications to accelerate the ET and eradicate CO2, and develop DER simultaneously.