Pairing Integrated Gasification and Enhanced Geothermal Systems (EGS) in Semiarid Environments

Abstract

We explore the feasibility of combining the circulation of supercritical CO2 in EGS reservoirs with integrated gasification combined cycle (IGCC) power generation. The symbiotic benefits of this pairing increase net power output over the use of either system in isolation, reduces water use per MWe, and substantially reduces fugitive emissions over conventional thermal power plants. A prototypical plant set in the arid southwestern U.S. (environs of Albuquerque, NM) could sustain anticipated circulation rates of 800–1600 kg/s of CO2 in a 200 °C reservoir, resulting in a thermal output of ∼150–300 MW-thermal to augment the 550 MW from IGCC. This design would reduce annual emissions by 8,200 tons of NOx, 20,000 tons of SO2, and 4.35 million tons of CO2 over conventional thermal plants in an optimal pairing.