Colloquia

Summary

The rapid electrification of transport, heating, and residential energy storage,driven by decarbonization goals, is expected to at least double electricity demand by 2050. This dramatic increase will place significant additional stress on Low Voltage (LV) distribution networks, many of which are already operating near their capacity limits. This thesis explores both the technical and socio-economic implications of a proposed strategy to mitigate congestion in LV electricity grids under a scenario of 100% penetration of distributed energy resources (DERs). The strategy focuses on deploying decentralized Home Energy Management Systems (HEMS) in each household, combined with a Direct Load Control (DLC) mechanism centrally managed by the Distribution System Operator (DSO).

The system leverages the ability of HEMS to optimize household energy usage by shifting consumption to periods with lower day-ahead electricity prices, theoretically alleviating congestion. However, when multiple HEMS units react simultaneously to the same price signals, they can unintentionally create new peak loads during low-price periods, further stressing the network. To address this challenge, a decentralized DLC mechanism is introduced. This mechanism dynamically and uniformly limits the power capacity of household grid connections during periods of voltage limit violations, triggering HEMS units to reschedule flexible loads accordingly. These limits are based on real-time voltage measurements obtained from monitoring units installed at both the substation and the end of the feeder.

Simulation results show that this approach effectively stabilizes grid voltage and ensures fair and efficient use of the network's capacity across all households. Crucially, this is achieved without requiring access to smart meter data, thereby maintaining compliance with Dutch privacy regulations. Furthermore, the strategy ensures equitable distribution of DERs along the feeder, preventing shutdown of DERS due to voltage violation. The performance of this proposed system is shown to be comparable to physically upgrading the network with 4x240 mm² XLPE cables. This proposed system can speed up the energy transition by utilizing the existing grid without the need for labor-intensive interventions and the infrastructure permitting process required for a cable upgrade. Finally, the thesis evaluates the cost-effectiveness, environmental impact, and scalability of the proposed approach.