Non-uniform electrical networks (meshed included), providing more reliable supply of electric energy to consumers, have greater losses than uniform ones. To upgrade such a network by reducing losses, special measures are provided, which should be done at the least cost. An effective measure of the kind would be introduction of opposing voltage or complementary reactances in some branches of the network. In this case, to determine the required parameters, a non-uniform meshed network should be disintegrated into separate cells – closed loops with equivalent node loads, which are the sum of node loads and the flows not belonging to a given cell. Then the circulating power of all cells is calculated, and the cell with the maximum circulating power is selected to be upgraded. For this purpose, in this cell the pre-defined opposing voltage or complementary reactance is brought. If the total power loss in the network after the first step of upgrading is not satisfactory, a next similar step should be taken, and a next cell singled out for upgrading. Such cell upgrading should be continued until the total losses stop decreasing.