Abstract
Industrial electrification efforts and the expansion of renewable generation, combined with lengthy grid infrastructure permitting processes, have created extensive queues for connections across European electricity systems, limiting the ability to connect new customers under existing market structures. This paper develops a coordinated flexibility trading mechanism, operated by an independent aggregator, that mediates trades between customers and the grid operator. The mechanism is formulated as a two-stage optimisation model, including a day-ahead scheduling stage followed by a flexibility market that coordinates capacity and energy trades under network constraints. Using a case study of an industrial distribution network with six customers, we show that coordinated flexibility trading can reduce load shedding and allow for additional non-firm connections without grid reinforcements by reallocating capacity rights and sourcing of flexibility. In network-wide coordination scenarios, the mechanism reduces total system costs by up to 15% compared to local-only coordination, with outcomes depending on the congestion type and magnitude. Our framework demonstrates that existing grid infrastructure can accommodate substantially higher connection capacity through coordinated flexibility mechanisms, offering a practical intermediate solution between costly grid expansion and nodal market efficiency.