4-E and life cycle analyses of a supercritical coal direct chemical looping combustion power plant with hydrogen and power co-generation

Abstract

Present work evaluates hydrogen and power co-generation of a supercritical (SuperC) steam based coal direct chemical looping combustion (CDCLC) power plant using high ash coal. Different cases of hydrogen co-generation have been considered with 0–900 MW of hydrogen production and 462-157 MW of electric power generation. In this study, CDCLC plant using iron based bimetallic oxygen carrier with co-generation is compared with CDCLC plant without co-generation and conventional SuperC coal fired plant without CO2 capture. The overall performance of all cases is compared based on 4-E (energy, exergy, ecological, economic) and life cycle analyses (LCA). A sensitivity analysis is conducted to optimise the operating conditions of CLC reactors. The levelised cost of hydrogen from CDCLC plant with 50% hydrogen and 50% power co-generation is estimated to be 1.94 €/kg. Further, the LCA conducted on the cogeneration plant by considering important stages reveals that the CDCLC plant stage is the highest contributor in greenhouse gas emissions (GHG) emissions and primary fossil energy consumption (PFEC). The key outcome of the study is that the CDCLC power plant configuration with higher hydrogen co-generation is energetically, exergetically, environmentally and economically efficient.