On Wednesday 17 September, the Agency for the Cooperation of Energy Regulators (ACER) validated the new Harmonised Allocation Rules (HAR) for long-term transmission rights, proposed on 27 March by the transmission system operators (TSOs).
The TSOs’ proposal included the introduction of a 15-minute market time unit on the ‘day-ahead’ electricity market.
Following a public consultation in spring 2025, ACER had until 29 September to give its opinion on the TSO proposal (see EUROPE 13628/24). It approved the proposal but also issued a number of clarifications and proposing additional revisions.
In particular, the Agency recommends that TSOs and national regulatory authorities review the arrangements between designated electricity market operators (NEMOs), which should “establish transparent rules for defining the single ‘day-ahead’ reference price in the event of decoupling”.
It also recommends that they review the rules applicable to the nomination of physical transmission rights, taking into account the introduction of a 15-minute market time unit on the ‘day-ahead’ market.
TSOs and regulators must now review the nomination rules and agreements between NEMOs to take account of the latest ACER updates.
To see ACER's decision: https://aeur.eu/f/ij4 (Original version in French by Pauline Denys)