Some facts as I understand them snarfed from the web - corrections welcomed...
rough cost of (wholesale) energy per kilowatt hour (kwh): ~5c
CO2 cost per kwh: ~1kg (coal power: http://cdiac.ornl.gov/pns/faq.html)
time for my (small) 1 litre (~ 1kw) kettle to boil when full is ~ 5 minutes which compares well with the theoretical energy for a 1litre at ~350kj, or 350 seconds time for 1kw . Hence power for a small boiled kettle is a killowatt for 1/10 of an hour, or 0.1 kwh
So I get...
Kettle boiling: costs ~.5c, and ~ 100g, ... the article says a kettle take 15g, which I don't get even close to; maybe clever people boil just enough to make single cups only?
If the article was true, Google doing "more than 200m" searches a day would spend ~ $20m a day on power, or ~ $7billion a year, consuming 100,000 megawatt hours, or a continuous drain of 4,000 megawatts (about the power output of a small US state). On the authors figures, total power consumption would be ~ 650 megawatts, which is still pretty huge, and would still be spending ~ $1billion a year.
Google use cheap, mass produced low power units in gigantic numbers - estimates are hard to come by, I will estimate 200,000 based on inflating some public estimates (e.g. http://arnab.org/blog/how-many-computers-does-google-have).
Energy cost of networking is significant, but I do not believe as great as machines; I'll add 50% for good luck. Utility server machines are dropping in power (~100-200w) but also require cooling, UPSs and network etc., so let's call it 500w all up (figures are difficult to get; everyone is selling something power center wise) - so I get 100 megawatts; or 1/6th of the author's estimate, or 1/40th of the true kettle figure.
I'd say that the author is overstating the case to make a political point - if I was cynical I'd point out the author has also just launched a business to 'green your web site' by installing monitoring software, estimating the energy cost of searches to it, and then buying carbon offsets on your behalf, so it is in his interests to overestimate such usage..