If the power consumption of a RPi for each household with someone like us is a major thing then I say we have come pretty far in reducing waste of energy. :-)

People don't want another thing to plug in even if it's low-power. IoT is still nascent and I already don't have enough outlets in my house...

I disagree. Google uses 1/4GW worldwide and that's less than a watt per user.

Where does that number come from?

One data center * 24 backup generators * 3 MW each = 72 MW per data center. Four of those = 288 MW > 1/4GW.

Google has more than three data centers.

Ah yes, that number is from 2011, published by Google. Can't find the original. But it was widely reported[1].

Assuming that they're doubling energy consumption every year they'd have reached 8GW in 2016. That's 8W per user if we assume 1 billion users. Energy usage of a Raspberry is not insignificant relative to even this.

Doing things at scale is vastly more efficient. And only a subset of Google services can be relegated to a Raspberry. Even if you host your own mails, are you ready to ditch the Google search index and Youtube?

[1] http://www.nytimes.com/2011/09/09/technology/google-details-...