An economic assessment method for flexibility enhancement technologies of thermal power plants

Abstract

High-level renewable energy integration imposes significant uncertainties into power systems. The negative peak load regulation (NPLR) and frequency regulation (FR) are needed for the security of the system’s operation. Thermal power plants are urgent to carry out flexibility enhancement to provide NPLR and FR. However, there are diverse flexibility enhancement technologies to be chosen. This paper proposed an economic assessment method of flexibility enhancement technologies to conduct thermal power plants to choose the best scheme. Firstly, the framework for the economic evaluation is proposed. The various flexibility enhancement technologies are classified based on the revenue model. Then, the revenue function of NPLR and FR are formulated under the ancillary service market. Finally, the economic indexes, such as, the internal rate of return (IRR), net present value (NPV), and payback period are calculated. The proposed methods are validated using a 200 MW power unit with a condensing steam turbine. The results demonstrated the effectiveness of the proposed framework.