Development of carbon capture and storage (CCS) hubs in Kazakhstan

• Kazakhstan's CO 2 emissions come from electricity sectors concentrated in the North. • Eight CCUS hubs in Kazakhstan aim to capture 115 Mt of CO 2 annually by 2060. • Ammonia and natural gas plants are prime candidates for CCUS. • Atyrau hub shows high CO 2 capture rates at relatively low costs. • Kazakhstan's CCUS hub infrastructure needs US$84.2 billion. The competitiveness of both the power and industry sectors in Kazakhstan is due to the use of cheap fossil fuels. Due to the projected large-scale deployment of renewable energy sources in the future, some portions of cheap coal and hydrocarbon use are planned to be phased out in Kazakhstan. In its net-zero journey, the country still intends to have GHG emissions from reduced use of fossil fuels and “hard-to-electrify” industries such as chemicals, cement, and iron/steel sectors. Carbon capture and storage (CCS) is a decarbonization solution to existing fossil fuel-fired power plants and other hard-to-abate industries in the net-zero age, which Kazakhstan officially plans to reach by 2060. This study covers three major research tasks on large-scale CCS deployment in Kazakhstan. The study first reveals the “low-hanging fruits” of CO 2 capture in the natural gas processing and ammonia production industries, with a low cost of capture of $29 per ton of CO 2 captured each, by comparing the costs of capture in Kazakhstan with those of power plants, steel factories, cement plants, refineries, and hydrogen plants. Secondly, this work shows that developing CCS projects in hubs of multiple emitters can bring cost-efficient deployment of CCS in Kazakhstan. Lastly, we presented our vision of how CCS could be a part of Kazakhstan's big net-zero plan in 2060. Our estimates show that 8 CCS hubs in Kazakhstan with a total capacity of 115 Mt CO 2 /year could cost $87 billion in capital expenditures (CAPEX) until 2060. While CO 2 capture remains the most expensive component of CCS process chains globally, compressing and transporting CO 2 poses significant cost challenges in Kazakhstan due to the long distances between emission sources and storage sites. Future research endeavors could explore automated tools to optimize logistical considerations and enhance the accuracy of cost estimations. Moreover, further studies should incorporate site-specific data to reduce assumptions and refine CCS potential assessments in Kazakhstan.