The theoretical part of this final paper describes distribution networks, their characteristics and specificities. Special emphasis is placed on low-voltage distribution networks, which, in addition to phase conductors, also have a neutral conductor, and earth as a return conductor. In this paper, the Backward-Forward algorithm was used for calculating the power flows of the low-voltage network, which is based on Kirchhoff’s laws and the calculation of voltage drops on all busbars of the network. This algorithm is convenient to use because it converges even in cases of large R/X ratios that are characteristic of distribution networks. In the experimental part, this algorithm was implemented in the Python program package. The BF algorithm was used to calculate the power flows of the radial distribution network of 9 buses and a network of 906 buses. It is shown that the developed algorithm is a powerful tool with which we can calculate the power flows of an arbitrary distribution network. To verify the accuracy, the results were compared with the OpenDSS software package and the accuracy was confirmed numerically using a very low percentage error of the order of 0.0001%.