At today’s TechCrunch Cloud Computing Roundtable event, a new storage company called Diomede launched in private beta with the goal of offering low cost cloud-based storage that is also very energy efficient. The basic premise behind the service is that not all data in the cloud needs to be immediately available, but that most people still pay for the immediate access anyway. While most data centers have their servers and disk drives operating 24/7 with near-immediate access, Diomede allows customers to designate files that they don’t need instant access to, and places them either as ‘nearline’ or ‘offline’. These files have an access time of five minutes or four hours, respectively, but cost only 1/12 as much as standard cloud providers to store and take as little as 1/60th the amount of energy. If you’d like to try it out, go to this page and enter the invite code ‘tcrunch’.

The service offers a full API to developers, and also allows them to view metrics like the power consumption of each individual file. Possible applications include allowing developers to set their redundant file backups (which rarely need to be quickly accessed) to ‘offline’, where they can be stored at only a fraction of the normal cost.

Deomede is the latest venture from Steve Iverson, who was CEO of MediaMax, a file storage company with a tumultuous history that closed its doors last year. While the company had its issues, it’s unclear if they can be attributed to Iverson or were primarily related to engineering blunders and investors.