Energy loss estimation in distribution networks for planning purposes

Because of increasing economical pressures on network operators, the losses in the subtransmission and distribution systems are becoming more and more important. It is usually not economical to exchange equipment for the sole purpose of reducing losses; however, it is an important criterion when deciding to implement changes in the network. The computation of the energy loss with a network simulation program is very laborious and the required data is usually not available. In the paper, an energy loss estimation method based on readily available data (i.e. peak power, average power, power loss at peak load) will be derived and implemented. For this purpose already developed approximation formulas will be reviewed for the use in current networks with today´s load characteristics. The estimation is used to obtain the energy loss for different networks as well as for the possible reduction of energy loss due to reconfiguration of existing networks. To compare and verify the results of the energy loss estimation, a computation of the losses with a network simulation program is implemented and a time period of one year is analyzed.