468543 Optimal Scheduling of Advanced Energy Plants with CO2 Capture
It is anticipated that the CO2 capture targets will need to be satisfied over a period of time, denoted here as ‘base time’, which is expected to vary from region/country to region/country. The base time for CO2 capture may be several months to a year or more. Therefore, any discrepancy in the CO2 captured and the target during the previous time instances can be accounted for in the future time instances. This is unlike typical control objectives where the deviation from the set point in the past might be completely neglected or be considered with lower weights in the future. Thus inclusion of CO2 capture in the scheduling problem requires the solution of an optimization problem with a large horizon. One challenge for this class of problems is the large size of the online optimization problem. Efforts to reduce the horizon can lead to undesirable closed-loop characteristics such as bang-bang actuation or inventory creep. In addition, the input sequence for a reduced horizon formulation may be suboptimal when compared to an infinite horizon control formulation. Our work has evaluated the optimal scheduler profile for CO2 capture rate over time by considering three penalty/tax scenarios including the possibility of a cap-and-trade policy. The presentation will include a proof for the
stability of the developed scheduler algorithm and highlight its application to an integrated gasification combined cycle (IGCC) power plant with CO2 capture.