Smart control of flexible end-user loads for managing electricity shortage situations, FHNW School of Engineering and Environment

Technologies

• OSTRAL
• Electricity shortage situations
• Flexibility
• Demand-side load control

In autumn 2022, large parts of Europe faced the risk of electricity shortages. In Switzerland, contingency measures for such situations have been prepared under the framework of OSTRAL (Organisation for Electricity Supply in Extraordinary Situations). At the highest escalation level, distribution system operators would be required to disconnect entire sections of the distribution grid on a rotating four-hour basis in order to significantly reduce electricity consumption within their service areas.

An alternative to disconnecting entire grid sections is the targeted control of flexible end-user loads, such as heat pumps, electric water heaters, and electric vehicle charging stations. Within Repower's distribution network, these devices account for a substantial share of the total winter electricity demand—approximately 50%.

Coordinated control of these flexible loads can help avoid widespread power outages. Although customer comfort cannot be maintained at its usual level during such emergency situations, essential household services would remain available. Customers would still have lighting, be able to cook, and maintain communication, while only selected flexible loads would be temporarily reduced or shifted.

To extend the Smartpower load management system for operation during critical grid conditions, several fundamental research questions must be addressed:

• Define and implement a centralized control signal for power demand management.
• Achieve controlled reductions in electricity consumption while minimizing impacts on end-user comfort.
• Design a stable closed-loop control system for adaptive load management.

Following comprehensive simulations and laboratory testing, the proposed approach will be validated through a field trial within Repower's distribution network.

This innovation will contribute to increasing the resilience of the electricity grid by enabling the management of extreme supply situations without the need for complete network shutdowns.