Effects of interruptible load on purchasing portfolio for load serving entities

In a deregulated electric power system, multiple markets of different time spans exist with various power supply instruments and various fluctuating prices. A load serving entity (LSE) has multiple choices from these instruments to meet its load obligations. Since interruptible load can be looked as an equivalent power to support reserve service in emergency, in this paper, it is regarded as such an equivalent power as the same as day-ahead energy and forward contract energy to form a portfolio. Taking Conditional value-at-risk (CVaR) as the risk measuring index, a midterm power portfolio optimization problem with risk management is presented. The study provides an insight into interruptible load market trade and its effect on the purchasing portfolio risk. Numerical examples are carried out to illustrate that interruptible load can effectively lower purchasing portfolio loss, and also the validity and rationality of the presented model have been demonstrated.