Novel approach to achieving net-zero carbon emissions for development and utilization of coal: Principle, methods, and cost estimation

China's energy mix is coal-dominated; therefore, it is unrealistic for the country to achieve carbon neutrality through complete decarbonization. As the world's largest carbon emitter, achieving global carbon reduction targets necessitates that China develops low-carbon, clean, safe, and efficient coal development and utilization technologies. This study proposes a new low-carbon coal development and utilization method that integrates in-situ conversion mining and mineral carbonation (ICMMC) to realize coal mining and separation, in-situ backfilling, in-situ conversion, energy storage, and carbon sequestration. This method addresses the technical bottleneck of slow mineral carbonation (MC) reaction rates that hinder the application of low-cost carbon sequestration engineering by utilizing in-situ backfilling strips to construct an in-situ carbonation repository, alongside a complementary in-situ layered carbonation process to enhance carbon sequestration efficiency. Life cycle assessment and levelized cost of electricity (LCOE) are employed to analyze the competitiveness and necessity of this new method compared to coal-fired power with carbon capture and sequestration (CPCCS) and onshore wind power with energy storage (OWPES) technologies. The results indicate that the carbon emissions of the ICMMC (0.091 kg/kWh) are much lower than those of traditional coal-fired power, and its LCOE of 0.463 CNY/kWh has a cost advantage compared to both CPCCS and OWPES over the next seven years. The findings suggest that the ICMMC system can partially replace CPCCS and OWPES, helping to reduce global carbon reduction pressure; it can serve as a transition technology that supports the decarbonization of energy systems in countries where coal is the primary energy source.