Ancillary services provision by aggregators and impact on distribution network operation

The growth of distributed energy resources (DER) connected at distribution network level and the current legislation concerning the participation of DER to the energy and ancillary services markets, are a huge opportunity to get flexibility services from these resources but at the same time a great challenge from the technical point of view. According to the latest indications from EU Directives, demand response and generation flexibility are encouraged in order to meet network balancing needs, but a new actor is required: the aggregator. This new participant has the duty to aggregate consumption and generation in order to offer flexibility products in the ancillary services market, while ensuring the technical feasibility and assuring revenues for its clients and itself. This work focuses on the structure and the business model of aggregators and discusses the technical implication that such role has on the distribution network.