TSO-DSO interaction in 2030/2040: scalability of the traffic light system concept in the project InteGrid

Excerpt

With the current increase of distributed energy resources (DER) connected within the distribution network, challenges faced by the distribution system operator (DSO) have also increased, particularly in terms of their scalability and replication in the network. However, once these devices are rolled out in the field, different business models arise in order to optimize the operation of such devices, and, consequently, challenges appear for the DSO. Such business models target the use of these resources as sources of flexibility for the transmission system operator (TSO) services. Hence, it is necessary to analyze the impact of including DER in the network and how these DER are to be controlled and to observe the impact of these control schemes on the network. In this context, the European project InteGrid [1] aims to provide the DSO with the ability to operate as a market facilitator while considering possible future scenarios. A traffic light system (TLS) [2] enables the DSO to become a market facilitator for energy services. The TLS aims to validate flexibility products in medium-voltage (MV) and low-voltage (LV) networks to ensure that no network violations occur when these flexibilities are aggregated and offered to the TSO. Through the deployment of the TLS in the Slovenian and Portuguese demonstrators, InteGrid examined the impact of current and possible scenarios (2030/2040) by conducting a full scalability and replicability analysis (SRA) [3]. The Slovenian SRA focused on the indirect coordination scheme between the TSO, who uses MV and LV flexibilities through a particular aggregator for the manual frequency restoration reserve (mFRR), and the DSO, who operates the MV and LV network. In this regard, a distinction between the aggregator types is drawn, as InteGrid encompasses two main types: the technical virtual power plant, which offers the flexibility sources to the DSO, and the commercial virtual power plant, which provides services to third parties, such as the TSO. The latter requires the coordination and validation of the DSO to ensure a safe operation of the flexibilities. …