But the environmental group is recognizing that some firms have taken meaningful steps to reduce their dependence on fossil fuels.
Energy regulations make it harder to consume renewables than it should be, and there's not yet a "cookie cutter" approach that can be applied from one project to the next, said Bill Weihl, who runs Facebook's sustainability efforts and previously had the same job at Google. But utilities are becoming more open to partnerships with data center operators, he said.
It helps when you're as big as Facebook and Google, who can apply pressure in return for the promise of their business.
"If we're going to bring you millions of dollars in revenue, we really think we should get the product we want," Google's Demasi said.
The imperative to make cloud services greener is great. Almost half the world's population will be connected to the Internet by 2017, according to research from Cisco. And if the cloud computing industry were a country, it would already be the sixth-largest consumer of electricity, just behind Russia, Cook said.
Efforts like the one to create a new energy tariff in North Carolina could pave the way for other utilities to take similar steps, Cook said, but the work is far from complete.
"The story's not yet been written; it's being written now," he said.
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