The research was carried out with the aim of optimizing the parameters of the trailed sprayer to reduce the total energy costs during its operation, taking into account possible crop losses. Computational experiments were carried out using a system energy mathematical model of sprayers based on the tractor MTZ-80, 82. The system under consideration includes subsystems - tractor, operator, sprayer, field, soil and crop (TOOPPU). As a criterion for optimizing the parameters of the sprayer, the total energy costs are taken, including, in addition to direct and indirect energy costs, the energy of the crop lost when the parameters of the sprayer are chosen incorrectly. For the accepted operating conditions of the sprayer (field area Fpolya = 60 ha; head length lgona = 0.8 km; travel distance lper = 3 km; strength factor of the field bearing surface Q1=0.9; volume of work Q=1000 ha; crop - spring wheat; number of weeds - 50 pieces/m2; number of tractors employed in the operation Ntrakt = 1 piece; working day Tdnev = 14 hours; planned yield YP = 40 c/ha; application rate of pesticides H3 = 150 l/ha; pump pressure Pnasosa = 3 MPa, air pressure in tires Pw = 0.16 MPa, number of wheels on one side of the axle Zk = 1 piece, coefficient of adhesion of wheels to soil Kscep = 0.6, coefficient of resistance to wheel rolling fperek = 0.1; soil density pz=1300 kg/m3; soil hardness H=1800000 Pa) revealed the presence of a combination of values of six parameters, when the total energy costs reach a minimum. the volume of the tank for pesticides is 5000 l, the width of the sprayer wheel profile is 0.2 m, the coefficient of distribution of the weight of the sprayer on its support wheels is 0.83. When turning the unit within the field, the total energy costs amounted to 4852.9 MJ/ha. With the same values of the optimal parameters of the sprayer, turning the unit outside the field led to a threefold reduction in total energy costs to 1365.4 MJ/ha. Widely used partial performance indicators of sprayers - productivity, fuel consumption per unit of treated area do not allow to identify ways to reduce crop losses.