Datacenters as Controllable Load Resources in the Electricity Market

Data centers, being major consumers of power, can play an important role in the efficient operation of electrical grids. This paper develops an optimization framework to allow data centers to operate as controllable load resources within the demand dispatch regime, a demand response (DR) program in which incentives are designed to induce lower electricity use not just during times of high prices but also when the reliability of the local grid is jeopardized or when the electricity supply and demand are unbalanced. Assuming the availability of geographically distributed and virtualized data centers situated in multiple regional electrical markets, the basic idea is to migrate the workload in the form of virtual machines (VMs) between these centers to maximize the expected payoff. The proposed framework addresses issues specific to the demand dispatch of data centers such as timeliness of VM migrations and the impact of geographic distance on migration times. It also explicitly incorporates risks that may cause the load curtailment operation to be ultimately unsuccessful and result in monetary losses to data center operators; specifically, variability in network bandwidth that can cause uncertainty in VM migration times as well as the uncertain payoff when participating in DR markets. A set of case studies involving datacenters participating in an economic DR program is used to validate the framework.