Energies, Vol. 18, Pages 4738: Decarbonization of the Power Sector with CCS: Case Study in Two Regions in the U.S., MISO North and SPP RTO West

Energies, Vol. 18, Pages 4738: Decarbonization of the Power Sector with CCS: Case Study in Two Regions in the U.S., MISO North and SPP RTO West

Energies doi: 10.3390/en18174738

Authors:
Ivonne Pena Cabra
Arun K. S. Iyengar
Kirk Labarbara
Robert Wallace
John Brewer

This paper estimates potential changes in the total system cost (TSC) of decarbonization of two regional transmission organizations (RTOs) in the United States (U.S.)—Midcontinent Independent System Operator-North (MISO-N) and Southwest Power Pool (SPP) RTO West. In particular, the study serves to highlight potential differences in technology costs between two decarbonization pathways at carbon reduction rates close to 100% (relative to 2019 levels) while maintaining system reliability. In Pathway A, decarbonization is achieved by replacing fossil energy (FE)-fired thermal power plants with variable renewable energy (VRE) technologies coupled with energy storage (ES). Pathway B considers retrofitting fossil fuel-fired units with carbon capture and storage (CCS) and the addition of VRE and ES. The results show that including CCS technologies in the path to decarbonization has a significant benefit from a system cost perspective. When summing up all system costs and avoided emissions over 30 years of operation of the decarbonized systems, the pathway that includes CCS is significantly more cost-effective. TSCs for MISO-N are at least USD 1279 billion (B) and at most USD 910 B under Pathways A and B, respectively. For SPP RTO West, Pathway A TSCs are at least USD 230 B, and Pathway B TSCs are at most USD 153 B. TSCs of Pathway A are 1.4–8 times larger than the total system costs of Pathway B. When CCS is not included, the cost per ton of carbon dioxide (CO2) avoided is estimated to be USD 124–489/ton for MISO-N and USD 248–552/ton for SPP RTO West. When CCS is included, the cost of avoided CO2 is projected to decrease by 29–87% (mid-point estimate of 73%) with values varying between USD 64 and 114/ton and USD 74 and 164/ton for MISO-N and SPP RTO West, respectively. These differences highlight the need for consideration of all low-carbon-intensive technology options in cost-optimal approaches to deep decarbonization and the value of CCS technologies in the energy transition.