This figure is clearly wrong.  Similarly erroneous figures have been debunked at extreme length  in the past, see:

http://enduse.lbl.gov/Projects/InfoTech.html

for more.  I am actively engaged in work on this topic; anyone who has data is encouraged to contact me -- BNordman@LBL.gov .  I would discourage characterizing energy use of "The Internet" as the sum of the consumption of any device connected to it -- I think this confuses rather than enlightens people.  More useful is to report the consumption of key types of devices, such as network equipment, servers, storage, PCs, displays, etc.

--Bruce 

This must be wrong.  For one thing this survey cannot possibly understand what percentage utilization my computer and monitor is when connected to the Internet.  Besides my power consumption is already monitored and reported in other locations.  Let's try to come up with some more realistic numbers.  -doug

It may be 'wrong' but it might still be useful, if only for provoking some discussion about what the real figure is - what we want to measure, and how, and what we can then do with that information.  Doug's right that simply including the electricity consumption of my laptop because it is connected to the network doesn't really help - but it is a starting point.

The real danger is that this  5% figure is nice and round and easy to remember, so it is likely to become folklore, reproduced in innumerably powerpoint presentations around the world and never updated. One of the useful things we can do on wattwatt is, of course, ensure that better figures are both calculated and known about!

I agree, this is only a starting point.  However, Bruno's assertions were not presented in this manner. 

If we are interested in learning just how much power is consumed in Internet matters we can only make estimations based on spot checking and auditing "typical" users.  And don't forget that the Internet is orders of magnitude larger than just the world wide web.  I may be wrong but it is very likely that email alone is the largest piece of the pie.  -doug

By the way, I have two monitors and both are flat screens.  One is used whereever I go and the other is used intermittently.  The question is, "Am I a typcial user?" The answer is "Maybe."  -doug