Demand Response for Reducing Coincident Peak Loads in Data Centers

Demand response is a key aspect of managing uncertainty and reducing peak loads in electric grids. This paper considers the capability of a datacenter to provide responsiveness to grid signals through cooling system control. The strategy is based on precooling the center for provision of load reduction during demand response events, and is evaluated using a numerical model of a cooling system, validated against experimental data obtained from a small telecommunication data center. The pre-cooling strategy is applicable to a wide-range of demand response programs, but is illustrated on the example of an established critical peak pricing program; specifically the 4 coincident peak (4CP) program in the ERCOT ISO. Precooling reduced the annual cost of electricity used by the cooling system by 7.8 % to 8.6 %, while increasing the total energy use only by 0.05%. This translated into 2 % to 2.6 % reduction in the electric bill of the whole data center. The developed demand response strategy is suitable for data centers with power densities below 500 W/m2 which do not use server air containment systems.