Sensitivity analysis on UCG–CCS economics

Abstract

Underground coal gasification (UCG) facilitates the utilization of deep-seated coal seams that are economically not exploitable via conventional mining. A techno-economic model was developed to examine UCG cost effectiveness converting coal into a synthesis gas to fuel a combined cycle gas turbine power plant (CCGT) with subsequent CO2 capture and storage (CCS). Thereby, cost of electricity (COE) determination was exemplified based on a commercial-scale scenario developed for a selected target area in Bulgaria. Based on this approach, the present study discusses the results of one-at-a-time (OAT) and scenario based multivariate uncertainty analyses undertaken to assess COE sensitivity on 14 selected geological, market-dependent and technical model input parameters to quantify the uncertainties. The results show that geological model input parameters cause a COE variation of up to 2.8%, revealing a lower influence on COE than the technical components of the CCGT implementation with up to 14%, the synthesis gas composition with up to 9.8% and market-dependent parameters inducing a COE variation of up to 14.3% for CO2 emission charges.