Integrating more renewable electricity into the power system may increase carbon emissions

Abstract Increasing renewable integration in power systems is an important way of mitigating emissions in the Chinese power sector. Generally, coal-fired power plants are required to provide large-scale deep peak regulation (DPR) services in order to integrate more renewable energy. However, the carbon intensity of coal-fired power plants will significantly increase when providing DPR services due to inherent technical constraints. As a whole, the total carbon emissions of power generation may increase if the process of renewable integration cannot be coordinated with the operation of coal-fired power plants. This study examines the influence of increasing renewable energy integration on carbon emissions using plant-level data from a provincial power system in southern China. Under the existing DPR operation mode in China, increasing renewable energy integration can reduce emissions only when the minimum generation limits of DPR service providers are reduced below a certain threshold. Otherwise, more renewable integration will lead to more carbon emissions in the power system.