Storing syngas lowers the carbon price for profitable coal gasification.

Integrated gasification combined cycle (IGCC) electric power generation systems with carbon capture and sequestration have desirable environmental qualities but are not profitable when the carbon dioxide price is less than approximately $50 per metric ton. We examine whether an IGCC facility that operates its gasifier continuously butstores the syngas and produces electricity only when daily prices are high may be profitable at significantly lower CO2 prices. Using a probabilistic analysis, we have calculated the plant-level return on investment (ROI) and the value of syngas storage for IGCC facilities located in the U.S. Midwest using a range of storage configurations. Adding a second turbine to use the stored syngas to generate electricity at peak hours and implementing 12 h of above-ground high-pressure syngas storage significantly increases the ROI and net present value. Storage lowers the carbon price at which IGCC enters the U.S. generation mix by approximately 25%.