A scalable model was developed based on the 24/7 Energy Hub at The Green Village. The system includes short-term balancing through a battery, hydrogen production through an electrolyzer, and winter supply from a fuel cell. The validated component models were applied to a representative Dutch neighborhood consisting of 155 households (archetype 3) with an 250 kVA transformer, under projected 2050 demand and generation conditions. A set of 320 configurations was evaluated across multiple transformer capacities and hydrogen production sources. Feasible configurations were defined as those eliminating transformer violations while maintaining a positive annual hydrogen balance. The 2050 baseline exhibited 67.9 MWh/year of congestion. Of the 320 evaluated configurations, 56 met the feasibility criteria, all requiring a transformer upgrade from 250 kVA to 400 kVA. Two lowest-cost feasible designs were identified: a PV-only hydrogen configuration and a configuration that explicitly used the grid to produce hydrogen in off-peak winter periods. Both eliminated congestion while maintaining hydrogen self-sufficiency. However, total system investment ranged between €0.7–€4.6M, significantly higher than traditional transformer reinforcement (€34k).
The results from the case study show that decentralized hydrogen storage can technically resolve transformer congestion, but only when combined with moderate reinforcement and at substantially higher cost than conventional upgrading. Under current cost and efficiency assumptions, energy hubs have a flexibility purpose rather than being an economic substitute for grid reinforcement.