Natural gas oxy-fuel cycles—Part 3: Economic evaluation

Abstract

As part of the sixth European framework project on enhanced capture of CO2 (ENCAP), several novel power generation cycles with CO2 pre-capture methods are identified and the promising technologies are selected for a techno-economic assessment. For this analysis, the chemical process simulation package ECLIPSE is utilised. Following a detailed mass and energy balance calculation, the economic assessments of the Semi-close Oxygen Combustion (SCOC), Water Cycle and Graz as well as S-Graz Cycles is performed in reference to year 2004. The total capital cost estimation of the studied cycles is implemented in a bottom-up approach. Subsequently, the breakeven electricity selling price (BESP) is determined according to the net present value. Through the modification of parameters such as fuel price or capacity factor, the sensitivity analysis is carried out to assess the effect of endogenous or exogenous changes on the economic viability of the cycles. Among the systems, the S-Graz Cycle is the most cost intensive process. Yet, due to its high plant efficiency, it delivers the lowest electricity price and the lowest CO2-avoidance costs. The Water Cycle is the least capital intensive technology in this study. Due to its poorer plant efficiency however, the economics of this cycle scored third on the list.