This report presents first of all some considerations for greater harmonization of resilience assessment methodologies developed by distribution network operators. Harmonization is important to ensure the use of consistent metrics to evaluate resilience indices, its improvement requirements, the selection of interventions to be carried out, the benefits of interventions and economic rewards for network operators.
Afterward, the document reports possible strategic lines for coordination between the resilience plans of distribution network operators and that of the transmission network operator. Coordination was requested by ARERA [Italian regulatory authority for energy networks and environment] itself, to achieve greater efficiency and effectiveness of the plans both in the planning phase and during operation. To this end, it is necessary to consider network interactions in detail: notably, interventions on distribution during operation can alleviate or worsen (and also trigger cascading processes) transmission conditions, while multiple transmission faults can make reverse current feeding impossible in distribution networks.
Ultimately we want to identify the optimal interventions for resilience, a very complex and delicate problem also due to information confidentiality and different operators’ strategies. The characteristics of an integrated framework for intervention optimization, the barriers to be addressed and a possible roadmap are then outlined.
In the case study, which concerns two distribution networks and the transmission network, some potential benefits that coordination between distribution and transmission resources can bring to the resilience of the overall system are illustrated in a didactic manner.