On Mon, Dec 8, 2014 at 8:24 AM, parisse <bernard.pari...@ujf-grenoble.fr> wrote: > > > Le lundi 8 décembre 2014 16:24:30 UTC+1, Emmanuel Charpentier a écrit : >> >> How do you reach your estimate of 16 Wh/Google search ? Any source ? >> > In French: > http://www.planetoscope.com/electronique/980-emissions-de-co2-par-les-recherches-sur-google.html > 7g CO2/request. > Google's own published estimates are much lower (0.2g/request), but I'm not > sure we can trust them.
Here is Google's published estimate: http://googleblog.blogspot.com/2009/01/powering-google-search.html The published estimate ends with "The Sunday Times clarified its article on the energy consumed by a Google search, accepting our calculation that a single search accounts for about 0.2g of carbon." > Google power consumption is 260e6 W according to > http://inhabitat.com/infographic-how-much-energy-does-google-use/google-energy-use-infographic-2/ > for a little more than 200e6 requests to 1 billion requests per day (who > knows), that's 6Wh to a little less than 30Wh per request. Of course Google > does more than answering to requests, but one should also take care of all > the energy used outside google in the net. If the question is to compute the energy used per request, it is unfair to compute the energy used by *all* of the internet ("the energy used outside google in the net"!). That can only give you a very non-tight upper bound. > Therefore the 16Wh per request > estimate is probably in the right range. > I'm curious what the estimates would be for a server-centric computing model > for teaching. > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. -- William Stein Professor of Mathematics University of Washington http://wstein.org -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.