Abstract In order to achieve the Paris Agreement target of well below 2-degrees centigrade goal, developed countries have committed to reducing their emissions considerably during the coming decades. In order to achieve the ambitious target of an 80 % CO2 emission reduction in Japan by 2050 (compared to 2013 levels), various energy efficient and low-carbon technologies on the supply and demand sides of the energy system must be deployed at reasonable cost. In this study, we investigate the possibility of achieving the emission reduction targets in Japan using the TIMES-Japan framework, which employs a least cost optimization approach. The contribution of carbon capture and storage (CCS) in achieving the emission reduction targets is studied in various scenarios as alongside the evaluation of two important emission reducing technologies in the same energy sector as CCS. Results of the analysis reveals the importance of hydrogen import on the supply side and the electrification of steel-making furnaces (EAF) on the demand side in order to obtain “feasible” scenarios. The minimum amount of CCS capacity is calculated for each scenario and the results vary between 5 and 150 million tons of CO2 by 2050. The range of minimum CCS capacity is wide and affected by the availability of hydrogen imports and EAF for steelmaking in various scenarios; while extremely low CCS capacity results in a very high energy system cost. Based on the results of our analysis, policy implications for appropriate levels of CCS, hydrogen import and EAF deployment are discussed.