The future interaction between virtual aggregator-TSO-DSO to increase DG penetration

The increasing integration of massive quantities of generation from Renewable Energy Sources (RES) constitutes a challenge for the pan-European system. Reserve provision for the balancing of the network is an important service that, in principle, should be provided by all the units connected to the network, including RES generators themselves as well as flexible loads and storage systems. However, these resources have big peculiarities tied with their relevant technologies and could, beyond providing local services within the distribution grids (e.g. voltage regulation, congestion management), be available to provide reserve for the entire system, through the connection points to the transmission grid. This paper shows a more advanced dispatching management of distribution systems by resorting to more advanced Information and Communications Technology(ICT) systems able to transform distribution from a “passive” into an “active” system and market architectures able to incorporate scattered bids coming from distributed generation and active load. A delicate point is the interface between transmission and distribution that has to be managed in a coordinated manner between Transmission System Operators (TSO) and Distribution System Operators (DSOs) in order to achieve an overall efficiency target. ICT should also be key to allow a strict real-time coordination of the different subjects that are in charge to actuate the provision of ancillary services. Further, the paper shows as new actors could appear in the system like the “aggregators” who interface with the Market Operator to submit the bids for the provision of the services, with the local TSO to receive the consequent dispatching orders, with to the aggregated distributed resources (generation, flexible demand, storage) and with to the involved DSOs, in order to communicate how each dispatching order will in turn be dispatched among the distributed resources it aggregates.