Exploring the role of natural gas power plants with carbon capture and storage as a bridge to a low-carbon future

Natural gas combined-cycle (NGCC) turbines with carbon capture and storage (CCS) could be an important source of low-carbon electricity in the future. Factors affecting the market competitiveness of NGCC-CCS are examined by conducting a sensitivity analysis using the MARKet ALlocation energy system optimization model. The results indicate that widespread deployment of NGCC-CCS is better suited for a 30% energy system greenhouse gas (GHG) reduction trajectory than for a more stringent 50% reduction trajectory. Methane leakage rate, efficiency penalty, carbon dioxide (CO₂) capture rate, and natural gas price are found to be the strongest factors influencing optimal NGCC-CCS deployment, in that order. NGCC plays an important role in meeting mid-term GHG targets across all model runs. A large portion of NGCC capacity is later retrofit with CCS, indicating that NGCC can be both a bridge to a low-carbon future and an integral part of that future. Thus, retrofitability and siting near CO₂ storage should be considerations as new NGCC capacity is built. Regional results indicate that NGCC-CCS deployment would be greatest in the West South Central region, followed by the East North Central region. In a business-as-usual scenario, both regions have considerable electricity production from fossil fuels. Conventional coal and gas capacity are displaced under a GHG reduction target, opening the door for NGCC-CCS in these regions. NGCC-CCS market penetration is projected to have a mixed impact on air pollutant emissions and energy-related water consumption. Whether impacts are positive or negative depends on the technologies displaced by NGCC-CCS.