When you think of your carbon footprint you probably think of cars, or long haul flights, or maybe even what people eat. What you don't realise is that you're missing another key culprit: data.
The immense amounts of digital information we sling around the world requires a herculean infrastructure in the form of networks and data centres. To keep this all running requires power. A lot of power.
To put the amount in perspective, the ICT industries total power consumption in 2012 - simply to support data infrastructure - was 35%. That's more than the sum total used in manufacturing, which accounted for 18%.
This allies itself with another study we read last year which blew our socks off by saying that downloading games is less environmentally friendly than buying physical copies.
Obviously we're talking about an environmentally significant amount of energy here, and Greenpeace has compiled a report entitled 'Clicking Clean', which outlines energy choices made by major internet companies. Some have been very nice, others a bit naughty.
To clarify, the report only assesses environmental soundness with regard to internet infrastructure.
In first place came consumer golden boy Apple. Teacher Greenpeace was most pleased with its star pupil, and in all of the four categories - 'transparency', 'renewable energy commitment', 'energy efficiency'' and 'development' - Apple received an A.
Why such a high rating? Well, many of Apple's data centres are powered by renewable sources and it's shown great commitment to going 100% renewable.
When you've got $160 billion in the bank, you can afford to do super swanky things, like its recently announced data center in Viborg, Denmark which will be 'designed to capture any excess heat from the data center and pipe it into the town district's heating system.'
Facebook came in second, nearly scoring top marks across the board, lagging behind slightly in the renewable energy category. Google also deserves credit, coming in at third place and leading the field when it comes to deploying renewable energy.
Whilst Apple is planning on heating the lives of locals using its waste products, other companies don't come in for so much praise, with Microsoft and Amazon Web Services both faring badly.
Amazon, for instance, says that 25% of its data centres are powered by renewable energy, but locks down information on their power sources so tightly that Greenpeace wasn't able to confirm its claims. It was however invited to share more information, which could see it slip up (or down) the ranks.
This could be bad news: Amazon servers support some of the world's largest web services, such as reddit and Netflix, and video streaming is the largest factor in the 20% year-on-year rise in internet data consumption.
Other sites that fared badly in the report include eBay, which scored a measly 10% (compared to Apple's 100% score) on the Clean Energy Index. eBay has improved from its initial count of three coal-powered energy sources and seems happy to share its data, but still needs to look towards cleaner sources.
Overall Apple has, according to the report, created a new bar for the industry and is proof that a 100% renewable internet is possible. You can access the full report here to see how all the major tech companies compare to golden boy Apple.