Flexibility quantification and investigation of frequency support from single family houses equipped with heat pumps

This paper deals with the quantification of flexibility from space and water heating in houses equipped with heat pumps. As flexibility is determined by electricity consumption, an integrated model involving detailed representations of the heat pump, space and water heating is presented, to enhance the accuracy in estimating electricity consumption. A flexibility potential ranging between 2.1GW and 0.5GW are found, for outdoor ambient temperatures ranging between -10◦ C and 10◦ C respectively, for a power-system with a dimensioning fault of 1.45GW. Electric energy savings estimations are between 5.4GWh and 3.2GWh, when the indoor and water temperatures are reduced from 20◦ C and 55◦ C, to 18◦ C and 50◦ C respectively over 17.25hours, considering 24hours recovery period. During these conditions, the period with no electricity consumption varies between 0.85hours and 2hours. Electricity consumption as a function of time during the flexibility and recovery period, serves as valuable information for power balancing. Furthermore, a modified Nordic-32 bus system with a high share of renewable power installations is proposed. In this system, during the loss of a major generation corresponding to 12% of the load, frequency nadir reaches below 48Hz. By utilizing house heating flexibility corresponding to 5.9% of the load, limits the frequency nadir to above 48.8Hz.