Last month, Greenpeace launched a series of coordinated protests at Amazon, Apple and Microsoft locations to draw attention to the companies’ use of GHG intensive fuels in powering their data centers. The protests were a follow up to their recently released report, “How Clean is Your Cloud,” which criticized the companies for expanding their data centers without regard to the source of electricity. While some have questioned the report’s details, it nonetheless highlights an important issue. Major IT and cloud computing companies have been working to improve energy efficiency in their data centers, and yet mitigation of GHG impacts from power use has lagged. This matters, because recent growth of the internet and cloud-based computing is resulting in rapid proliferation of data centers and massive incremental power requirements.