How green is my download?

The Observer magazine has an interesting article by Lucy Siegel in the "It's not easy being green..." series - pondering if downloading is more carbon efficient than buying a CD.

Can I download and be green?
Downloading a music album exacts the same environmental price as making tea for 12

As we hurtle through the digital age, we tend to do so confident that new technology makes everything cleaner and greener. Kate Craig-Wood, founder of Memset, a managed hosting and cloud-computing provider, has taken a closer look at music downloads.

She based her calculations on a large sample group of servers, factoring in cooling and infrastructure losses in data centres although not the energy used to run the home network and PC or laptop. The headline news is that she found you could drive two miles in a small electric car or make tea for 12 people on the energy required to download and deliver a music album.

The point is that there is a carbon penalty for downloading, despite the physical lack of a CD. The energy used by downloads is around 7kWh per gigabyte (the average album will be in the region of 100MB). But downloading is still 40-80% more carbon efficient than buying a CD.

Alison Tickell, founder of juliesbicycle.com (strapline: taking the heat out of the music industry) is of the opinion that the CD-versus-download green debate should be retired. The march of downloads is inevitable – one track might be stored on multiple MP3 players or servers or burned on to CDs and all require different amounts of power. Responsible downloading isn't a sexy title but it's the next big hit.