Short term multi-objective hydrothermal scheduling

This paper investigates the short-term environmental/economic hydrothermal scheduling problem. The multi-objective optimization framework is proposed to model the Short-term Hydro Thermal Scheduling (SHTS) problem, while two competing objective functions are supposed to be minimized, simultaneously. The first objective function is to minimize the cost and the second one is to minimize the emissions caused by thermal units. In order to solve the presented multi-objective optimization problem and generate the Pareto optimal front, lexicographic optimization and Normal Boundary Intersection (NBI) method are employed in this paper. The main positive point with this approach is that it avoids the selection of arbitrary parameters and produces a set of evenly distributed points regardless of the objectives' scales. Afterwards, the most preferred solution among all Pareto solutions is selected utilizing a fuzzy satisfying method. The proposed model is implemented on a sample test system comprising four cascaded hydro generating units as well as three thermal units. Furthermore, the proposed method is implemented on IEEE 118 bus test system. The obtained results show the efficiency of the proposed multi-objective method to solve the SHTS problem compared to other methods recently employed. (C) 2014 Elsevier B.V. All rights reserved.