Economic dispatch (ED) problem is one of the most important issues in the operation of power systems. The objective of ED problem in electric power generation is to schedule outputs of all generating units so as to meet load demand at minimum operating total fuel cost, subject to equality constraints on power balance and inequality constraints on power outputs. Modeling valve point effects leads to non-convexity into the mathematical models. The mean squared error (MSE) of an estimator is one of many ways to quantify the difference between values implied by an estimator and the true values of the quantity being estimated. MSE is a risk function, corresponding to the expected value of the squared error loss or quadratic loss. MSE measures the average of the squares of the errors. This paper proposed an efficient approximation for non-convex ED considering the valve-point effects and presents a solution by approximation based MSE on non-convex objective function of this problem in order to determine the feasible optimal solution. The proposed methodology is applied on different test systems and compared with the most of the recent methodologies. Obtained results confirm that the proposed approach is capable of obtaining higher quality solution efficiently, especially in large scale power systems.
