The US Environmental Protection Agency is wrapping up work on an Energy Star programme for datacentres that it hopes to launch in June.
The goals of the programme are to give organisations more incentive to improve the energy efficiency of their data centres, and also give them a way to track the results of efficiency projects over time, said the EPA's Alexandra Sullivan, who described the programme at the Green Grid datacentre conference.
Datacentres that take part will use an online tool that ranks their efficiency on a scale of 1 to 100. Those that score 75 or higher can request an audit from the EPA, which then awards the Energy Star certification.
The EPA has become increasingly active in data centres. It already has an Energy Star programme for x86 servers, a programme for storage equipment is underway, and it said it had started work on an Energy Star programme for uninterruptable power supplies, or UPS systems.
Those programmes are designed to help companies choose energy efficient products. The data centre programme is different in that it is more incentive-based. With public awareness about environmental issues so high, the EPA hopes companies will see an Energy Star rating as a potential marketing tool.
The EPA already rates the energy efficiency of 18 types of buildings, including offices and hospitals. The main criteria for those are floor space and hours of operation, but it needed a different system for data centers.
The measurement will be based largely on PUE (power unit efficiency), which measures the total power supplied to a data centre, divided by the amount that actually reaches IT equipment, rather than being lost to cooling systems and inefficient power supplies.
The EPA will also take into account the energy output from the UPS systems. That means that while data centres with good PUE scores will tend to get higher rankings, PUE will not be the only factor, Sullivan said.
The programme is likely to stir some debate. Some attendees at the Green Grid event were surprised other criteria won't be included, such as whether a data centre is located in a cool or warm climate, or the level of redundancy it provides.
"You have to take the environment into account because it's easier to have a low PUE score if you're in a cold climate," said Don Klein, vice president of marketing and business development with Modius, which makes tools for measuring data centre energy use.