Social Welfare Maximization in Transmission Enhancement Considering Network Congestion

Transmission enhancement in a competitive electricity market is analyzed in terms of its impact on the social welfare. A formulation of social welfare and the utility functions are derived in this research. Variations of supply and demand during a year are considered in transmission enhancement decisions. The proposed social welfare optimization problem is solved to determine the transmission congestion status under the optimal condition of the existing system. Transmission enhancement options are compared quantitatively to demonstrate their ability to increase social welfare, which provides valuable information for long-term transmission. The proposed method provides a systematic and quantitative tool for social welfare evaluation that is not available in industry today.