Experimental analysis of flexibility change with different levels of power reduction by demand response activation on thermostat controlled loads

This paper studies the flexibility available with thermostatically controlled loads (TCLs) to provide
power system services by demand response (DR) activation. Although the DR activation on TCLs can
provide power system ancillary services, it is important to know how long such services can be
provided for when different levels of power reduction are imposed. The flexibility change with
different levels of power reduction is tested experimentally with domestic fridges used by real
customers with unknown user interaction. The investigation quantifies the flexibility of household
fridges and the impact of DR activation in terms of deviation in the average temperature. The
maximum possible power reduction with the cluster of refrigerators is 67% and the available
flexibility with the cluster of refrigerators is 10%. The resulting deviation in the average temperature
is 14%.