The Seattle Times reports it used enough electricity to power 24,000 homes.
The software company is looking to reduce its power bill by finding other ways to cool the acres of computer servers that handle e-mail and digital transactions over the Internet.
The data center was the third-largest customer last year of the Grant County PUD. Microsoft and other tech companies have located in Grant County to take advantage of the utility's relatively low rates for electricity from two Columbia River dams.
With data centers all over the world, Microsoft has been experimenting with cooling methods to reduce power demand.