Why? Because apart from cluttering our headspace, it’s quietly sucking energy away in the background. Global data centres are storing exponentially more data each year, with a wopping leap predicted from 2% of the world’s electricity consumption to 8% by 2030.. Every bit of data contributes to that. So the killers are not so much the spam emails, but the work ones where we hit ‘reply all’ or ‘cc’ the world, along with a heap of attachments.