Computation and uses of the energy flows for the distribution system analysis over time intervals

The liberalisation of the electricity markets has increased the need for a better knowledge of the time evolution of the system operating conditions. In particular, the shape of the load diagrams plays a relevant role in the definition of the market transactions among the market operators and in the possible formulation of dedicated tariffs to be applied to noneligible customers. A basic tool for introducing the time variable in the study of the distribution system behaviour is the computation of the "energy flows", requiring a well-defined model of the evolution of real and reactive power loads and generation. The paper presents an application of the "energy flow" computation to the formulation of energy-based indicators and to quantify the effects of the introduction of local generation sources into the distribution system.