Low-carbon transition paths and benefits for the power sector at city level: A case study in Zhengzhou, China

Abstract

The power sector significantly contributes to global greenhouse gas emissions, making its transition to low-carbon energy crucial for achieving carbon neutrality. Zhengzhou, recognized as one of the China's "National Central Cities", has a high energy demand. Its power sector, which is primarily reliant on coal, is responsible for half of the city's CO2 emissions. The low emissions analysis platform (LEAP) model serves as an effective tool for exploring the power sector's transition to low-carbon sources. However, studies on the combined reduction in air pollutants and CO2 at the city level are scarce. This study focuses on Zhengzhou's power sector, examining the power composition, coal usage, CO2 and air pollutant emissions, social costs, and employment effects across five scenarios using LEAP. The five scenarios are the business-as-usual scenario, the reference scenario, the carbon neutrality scenario, and two optimization scenarios with different carbon peak and carbon neutrality time. CO2 emissions will peak in 2030 at 34.6 Mt in the reference scenario, and in 2022 at 32.4 Mt in the carbon neutrality scenario. Emissions in the reference and carbon neutrality scenarios will decrease by 64.8% and 75.2%, respectively, from those in the business-as-usual scenario due to emission reduction strategies. In the carbon neutrality scenario, coal power reformation is the most significant measure, accounting for 45.7% of the total CO2 reduction compared to that in the business-as-usual scenario, followed by the integration of external electricity (17.8%) and solar energy (13.6%). This scenario also demonstrated a strong synergistic effect on reducing air pollutants and CO2 emissions. Although the carbon neutrality scenario incurs costs 60.4 billion yuan higher than those of the reference scenario, its CO2 mitigation cost is 66.1 yuan/t lower. This indicated that more rapid CO2 reduction, despite higher economic inputs, is justified by ambitious CO2 reduction goals and environmental benefits. Enhancing the use of renewable energy technologies for research and development to lower costs could increase the economic feasibility of the carbon neutrality scenario. In the two optimization scenarios, complete elimination of CO2 and air pollutant emissions is achieved by 2060, with all the electricity generated from renewable sources, although issues of uncertainty and stability need to be addressed. The study also highlights that renewable energy development will significantly boost employment, with an estimated 1.19 million jobs in 2060 in the carbon neutrality scenario. Finally, the paper concludes with a sensitivity analysis and offers policy recommendations for the power sector's low-carbon transition.