1. A method of optimizing a query, comprising: receiving a query submitted for execution; determining a plurality of execution plans for the query; for each execution plan in the plurality of execution plans: determining a power consumption value for the execution plan; and determining a monetary cost for executing the query according to the execution plan, based on one or more pricing values and the determined power consumption value for the execution plan; and selecting a first execution plan from the plurality of execution plans to use in executing the query, wherein the first execution plan is selected based on the determined monetary cost for the first execution plan.