Risk-based Distribution Planning tool for a fair comparison among conventional planning solutions and flexibility exploitation

The growing presence of distributed generation and the increment of energy-intensive loads in the transport and thermal sectors have highlighted the strategic importance of the electric distribution systems, whose operation is becoming more and more complex due to power flow inversions, line congestions and voltage regulation. Future scenarios, linked to recent European strategic development plans and in general to the actual energetic transition, will require huge network investments to preserve high levels of quality and reliability on the distribution system. These investments can be reduced or deferred by resorting to flexibility exploitation offered by Distributed Energy Resources, as generators, prosumers, storage devices and electric vehicles. To assess the validity of such alternative solution for the distribution network operation is a difficult problem that requires the estimation of long-term benefits and costs, probabilistic models, and risk calculations. In the paper, a planning tool for distribution system, developed in the past years and able to consider all these aspects, has been applied extensively on several MV distribution feeders to try to give some preliminary answers to open questions related to flexibility, like how much services are needed, what kind of services, when they must be requested. All these data are crucial to design a fair flexibility market where DSOs may procure these services, as suggested by recent European directives and National regulation acts.