Oxy-combustion of coal, lignite and biomass: A techno-economic analysis for a large scale Carbon Capture and Storage (CCS) project in Romania

• In-depth techno-economic assessments of oxy-fuel combustion power plants.
• Oxy-combustion delivers reduced carbon capture energy and costs penalties.
• Evaluation of fuel quality influence on oxy-combustion power plant performances.

Power generation sector is facing important challenges to develop energy efficient solutions at the same time with reducing the greenhouse gas emissions (mainly CO2). Oxy-fuel combustion is a promising power generation technology for reducing both energy and cost penalties for CO2 capture. This paper presents a detailed techno-economic analysis for oxy-combustion power plant to generate about 350 MW net power with a carbon capture rate higher than 90%. Both fossil fuels (coal and lignite) and renewable energy sources (sawdust) were used to fuel a super-critical power plant (live steam parameters: 582 °C/29 MPa). The assessment is based on numerical analysis, the models of various power plant sub-systems being built in ChemCAD and Thermflow software. As benchmark option used to quantify the CO2 capture energy and cost penalties, the same super-critical power plant without CCS was considered. The investigated coal, lignite and sawdust oxy-combustion cases show an energy penalty of 9–12 net efficiency percentage points, 37–50% increase of total capital investment, the O&M costs are increasing with 7–15% and the electricity cost with 54–95% (all compared to coal-fuelled non-CCS case). Sensitivity studies were also performed to evaluate the influence of various economic parameters on electricity and CO2 avoidance costs.