In a last hurrah for dying physical disc formats, Blu-ray can finally claim it has (definitively) won the format war. This is thanks to Facebook sharing, yesterday, that it uses Sony’s disc format as a means of cold storage.

With more than one billion users uploading photos, it’s a big challenge to maintain storage for all of those digital files – especially in a way that’s efficient and affordable. Facebook’s vice president of engineering, Jay Parikh, detailed the company’s latest storage prototype at the Open Compute Summit.

Rather than using hard disks, Facebook’s new storage system uses Blu-ray disks to archive older data. It’s not removed from the active network, but it’s put onto the slower disc-based format because it’s unlikely to be accessed any time soon. Parikh says that the system is only 50% of the cost of a similar hard drive-based solution, and saves 80% in energy usage. In current form, it can store up to 30 petabytes, though it’s active for only 1 petabyte of storage at the time. That’s around 10 000 Blu-ray discs. The system can be seen in action, in a video that Facebook posted.

If anything, it highlights the needs for companies to be innovative with their data centre solutions. Many storage providers still rely on hard drives, which, with their spinning motors, consume a lot of power. Solid state storage is all well and good when performance is required, but it’s a very cost-inefficient solution for long-term storage of data that’s not accessed often.

So, when’s the last time you accessed your profile photos from 2007?