Interesting. I'd like to see a similar test for OS X - at least anecdotally, Chrome seems to destroy my battery life compared to Safari (though to what extent App Nap helps Safari in that regard, I'm not certain.)
Get 4h45m with Chrome versus 6h30m with Safari doing the same tasks daily on a 2011 MBP i7.
Not overly bothered as I work right next to a power socket all day every day but it's an interesting statistic.