Abstract: A method for controlling operation of a vapour compression system (1) is provided, the vapour compression system (1) comprising two or more refrigeration entities, such as display cases. A signal representing a reference power consumption is received and compared to an actual power consumption of the vapour compression system (1). Based on the comparison, local controllers (3) calculate a setpoint temperature for a corresponding refrigeration entity, in order to obtain a power consumption which is equal to the reference power consumption. Each refrigeration entity is controlled in accordance with the calculated setpoint temperatures.