Computers, carbon emissions and hot air

In a brief and informative note published last week, the UK Parliamentary Office of Science and Technology (POST) reports that greenhouse gas emissions from information and communication technologies (ICT) are comparable with those from commercial aviation. Of course the figures may be out of date within a few months, but still they nicely illustrate a negative environmental impact of our much-lauded information society.

The energy consumed by ICT includes that used in home and office PCs, many of which are left running overnight for no good reason. But the bulk of the electricity goes into powering the rapidly expanding data centres that hold the emails, blogs, photo and video albums of millions of ordinary ‘netizens’, and on which government agencies and private businesses rely. Data centres currently account for around a quarter of ICT emissions, and some 2–3% of the UK’s total electricity use. We should expect this figure to rise dramatically in the next few years.

POST says that PCs should be switched off at night, possibly through the action of centralised “active power management” software. The report also notes that energy-efficient hardware such as multi-core processors has so far not been matched with operating system and application software that makes full use of the hardware features. Replacing desktop PCs with laptops is another good idea, given that they consume as little as a third of the energy of a typical desktop machine.

My own humble proposal would be for computer users to forego the questionable convenience of so-called ‘cloud computing’, in which personal data such as emails, calendars, browser bookmarks and shopping lists are held on centralised servers, only to be lost for ever when overworked hard drives fail or stoned operators press the wrong buttons. It would also help if Comment is Free and spEak You’re bRanes commenters were to shut up and get back to work. Millions of tonnes of hot air would not be emitted, and what a blessing that would be!