PNNL

Abstract

By combining the capabilities of two separate energy and economic models, the top-down MiniCAM and the bottom-up Battelle CO2 -GIS, the authors are able to demonstrate the significant impact that policies to stabilize atmospheric concentrations of CO2 at 450 ppmv and 550 ppmv would have on the existing asset base of the U.S. electric utility industry. Using the so-called “WRE” emissions stabilization pathways, the authors show that in the WRE450 case 98 percent of the capital stock of U.S. fossil power plants must be replaced with state of the carbon dioxide capture and storage (CCS)-enabled power plants by the year 2050. However, in the WRE550 case while the burden is less, it falls squarely on the shoulders of the U.S. coal-fired units which need to be completely replaced with Integrated Gasification Combined Cycle (IGCC) + CCS units while conventional natural gas-fired power generation and resulting emissions are allowed to grow during this time period. By 2050, these two cases result in approximately 54,780 million tons of CO2 being stored in various geologic formations in the more stringent 450 ppmv case and 23,800 million tons of CO2 being stored in the 550 ppmv case. Because of the heterogeneous distribution of the U.S. electric power sector’s assets, this demand for CO2 storage places varying demands on candidate CO2 reservoirs with the storage capacity of some reservoirs being significantly depleted by the year 2050.