The Adaptive Fridge – Comparing different control schemes for enhancing load shifting of electricity demand

Load balancing in electricity grids becomes a more sophisticated problem by the increased availability of timevarying stochastic availability of electricity from renewable resources. Demand side management by load shifting is one attempt to cope with this problem. In this paper we discus and compare two control strategies to use the thermal storage of electrical household appliances as balancing power. For this objective we analyze a simulation model of 5000 controllable refrigerators with respect to the ability to shift their energy demand depending on parameterized external signals. Both control strategies can be used for short term reserves with delivery within 15 minutes of time, but they differ in possible shapes of the resulting load curves and in the reaction time of the controlled system.