Abstract: This article covers the problems of energy saving in air blowers of biological wastewater treatment plants. The parameters of the aeration system of air blowers and their energy saving studies were analyzed. By determining the parameters of the effluent in the aeration tank, the parameters of the aeration system of the air blower were determined. Energy values were compared by comparing the frequency of the asynchronous motor with the speed rectification method depending on the load of the propulsion devices, and energy saving capabilities were identified. Results of the research are given in tables and graphs.