I don't know if this has already been posted but, here goes ...

How – and why – does renewable energy fit into this idea?
There’s a recognition that we’re going to need more and more electricity. Some of the ways we get it now might be problematic looking forward, but green energy – basically wind, solar and hydro – are incredibly attractive because they don’t pollute and are abundantly available.
And so, there’s a recognition that, if we’re going to manufacture something with renewable energy, maybe the thing we want to manufacture is data – that is, computation. That’s because it’s much less expensive to do it that way.
If you look at a data center right now – if you go out and buy a computer and put it in a room and use it for five years and pay normal amounts for energy over the first five years – on average, you’re going to spend about as much for electricity as you’re going to pay for the computing power you’ve got there. You’ll spend about as much for electricity as you’re going to pay to buy the computer and put the software on it and everything else.
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