SageBrush wrote:So on average, Search today (presuming no advances in computing efficiency -- obviously not true) is 0.00085% of the world's electric footprint. I estimate a search query as consuming one watt-hour of energy, although Google's commitment towards powering its data centres with renewable energy drops the actual carbon footprint dramatically.
I'm willing to give Prof. Wierman the benefit of the doubt based on his credentials. I highly doubt that he was trying to deceive anyone. At the same time, he may have made some very questionable assumptions. I don't know.
That Guardian article also mentions that efficiency at Google has improved 3.5x since 2011, so Dr. Wierman (a CS/Math professor at Caltech) may have been using old information. Further, a single Google search actually involves quite a number of operations besides straight text search. They are searching as you type (multiple searches), running ad servers, and checking/loading shopping data, for instance. Further, there are significant costs to all of the web spidering to gather the data to be searched, so perhaps Prof. Wierman may have been thinking in terms of amortizing those costs across all Google searches (who knows). He may not have been accounting for the use of renewable energy. He may have been lowballing the amount of energy used on short distance flights.
So, while I'm skeptical that 1000 characters' worth of Google searches (or a single search with 1000 characters?) really would generate the same carbon footprint as a LAX-->LAS flight, I'm also very skeptical that searches use only a few watt-hours of energy in total.
Anyway, I'm not terribly concerned about this particular point, as I'm not going to change my online behavior one way or the other. The big picture is that data centers have become a rather significant part of the world's energy usage!