This paper mainly studies the algorithm of load optimal distribution with both economy and environmental protection of thermal power units

and establishes a multi-objective load distribution model taking valve point effect into account.The algorithm of autonomous writing is applied

then to be decided Pareto Front(PF) is obtained.The core part of this algorithm is the combination of multiple objects

the removal of similar individuals at the same layer and the reservation of different individuals at different layers.The load optimal distribution examples of 6 units are given in this paper.The simulation results verify the rationality of the model and indicate this method can further reduce the fuel cost of thermal power units and the emissions of pollutants.Finally

by combining with the TOPSIS theory and discussing the differences between the load distribution schemes applying different target weights

this paper proves the determination of the TOPSIS-based multi-object load distribution schemes depends on the significance of their goals in decision making.