Simultaneous Imbalance Reduction and Peak Shaving using a Field Operational Virtual Power Plant with Pumps

The Dutch electricity infrastructure is challenged by the deployment of large numbers of heat pumps in newly-built domestic residences. An example is the apartment complex of Couperus in The Hague where 300 apartments are heated by individual heat pumps. This building was operated as a Virtual Power Plant for ten months. Using the PowerMatcher as a coordination mechanism, the VPP balanced a near-by wind farm providing a peak-shaving service to the local distribution station. Flexibility was provided by shifting the operation of the heat pumps in time, which is dependent on a certain bandwidth in the indoor temperature in the households. In this way up to 21% of the power drawn by the heat pumps was made flexible without infringing user comfort. Using this flexibility, 94% of the wind farm imbalance was reduced. Further, the system successfully performed peak-load reduction at the LV-to-MV substation simultaneously to the VPP operation. During the test indoor temperatures and the status of the heat pumps were recorded to secure user comfort. The Couperus project is one of a few smart grid demonstrators that did not include friendly users only, as all occupants in the apartment building were included in the demo. Therefore, the operational temperature bandwidth was set to a conservative value of 0.4 °C to avoid any loss of comfort. As a result, no complaints of the inhabitants with respect to the temperature were reported