ERCOT zonal congestion management

Abstract

This paper introduces the method of ERCOT congestion management and settlement. This method has some limitations if there are not enough bids to resolve all the zonal congestions when ERCOT implements the direct allocation method for settlement of zonal congestion cost. An enhancement for zonal congestion management is proposed to introduce artificial balancing energy bids into the optimization function to ensure a feasible solution and reasonable and consistent zonal market clearing price and shadow price. A case study is conducted to illustrate the ERCOT congestion management and settlement process as well as the proposed enhancement.