The Hungry, Hungry Cloud
Here's a startling statistic: If all the cloud computing services in the world were an actual country, that nation would be the about the sixth-largest electric power consumer in the world.
NPR reports that researchers at Greenpeace place the cloud right after Germany and before Russia.
That staggering volume of power consumption is driven by the massive data centers that store data around the world, allowing users to pull up documents and apps anywhere. The New York Times reported that in 2012 the cloud consumed 30 billion watts of power, as much as is produced by 30 nuclear power stations.
This has already led to some drastic measures by big data center users. Facebook has located a data center just outside the Arctic Circle to take advantage of the naturally cooling temperatures. Apple Inc. (Nasdaq: AAPL) now powers its cloud with a mix of solar, hydro-electric and wind-generated electricity.
The trend towards more distributed data centers might make it easier to co-locate the storage end of the data center with solar power set-ups, wind farms and hydro-electric power plants. The front-end servers and a fast connection would be in urban areas, while the storage would be in rural areas where it easier to find and fund a power source. (See Reliance Rebrands With Its Head in the Cloud.)
Nonethless, it's worth asking just how we'll keep powering the cloud as it continues to get bigger.
— Dan Jones, Mobile Editor, Light Reading

Let me give you an example: http://engineering.osu.edu/news/2013/06/ohio-state-pushes-clean-coal-technology-ahead
This could make coal of all things one of the best sources of clean energy that we have. I think assuming that technology won't change all of this is bad. If I use nuclear as an example, I lived in South Florida for about 15 years. Turkey Point Nuclear Plant took nearly a direct hit from Hurricane Andrew and was just fine. The Japanese plants got hit with their issues and that was a problem.
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Let's keep that one out until someone figures out how to neutralize nuclear waste... you really don't want to leave in a 2mile radius from a nuclear plant, and you don't want a nuclear waste facility in your backyard either, so what would you do?
Question is, does the cloud need to be the giant we're building today, or can we live with less?
Hydro is considered such an environmental issue that nobody (in the US anyway) is building new Hydro power. Solar has the capital and space issues. Wind has space, sightlines, and killing birds issues. Both wind and solar have storage issues. Nuclear has waste and other safety concerns. Fossil fuels have global warming issues.
And of course costs are not equal between sources: http://en.wikipedia.org/wiki/Cost_of_electricity_by_source
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