A method for determining power consumption in a data storage system is provided. The method comprises determining data access patterns for at least a first storage device in a storage system based on operations performed by the first storage device; and calculating power consumption for the storage system by interpolating costs associated with the operations performed by the first storage device, wherein the cost associated with each operation is determined based on: (1) various levels of activities for the first storage device and a mix of workload characteristics, and (2) predetermined power consumption measurements obtained from one or more benchmarks for same operations performed by a second storage device in a test environment.