The body first announced its existence last year, when it named its backers as Hewlett-Packard Co, IBM Corp, AMD and Sun. Since then it has kept a very low profile, but this week it said that it has finalized its charter, and it named new members – Intel, VMware, Microsoft, APC, Dell, Rackable Systems, and SprayCool.

In fact Intel and Microsoft were a part of the body last year, according to the Green Grid, but until now have not been prepared to reveal their backing for the group.

There are still sizeable gaps in the support however. Cisco for example is notable by the absence of its enormous data center networking bulk, as apparently are major storage players such as EMC or Hitachi.

Cisco yesterday however said that it is very interested in joining the consortium. EMC meanwhile is already is a member, via its subsidiary VMware.

The Grid said that engineers from EMC’s storage business have already been present in the consortium’s working groups. But the consortium’s bye-laws will not currently allow EMC to buy a second membership, and so add its name to the Grid’s roll-call. That is ironic, given that VMware usually likes to project itself as an independent company to EMC.

The self-declared aim of the Green Grid be achieved primarily by publicizing best practices in data center energy management and developing metrics or measures of power consumption and heat generation for data center equipment.

The Grid cited a Gartner prediction that by 2008 half of the world’s data centers will run out of power. Since that will put a significant dent in customers’ desire to buy any more IT gear, it is in the industry’s interests to address this issue. And of course the vendors that address it the best will make the most sales.

The risk is that the Green Grid will turn into a mere marketing tool, one that will generate yet more hot air. A spokesman for the Grid said however: This is not about marketing, it’s about engineering. We’ve already had members that could have used it for marketing when they were launching products over the last year, and they didn’t. It’s a gentlemen’s agreement.

There is also the possibly that commercial politics will see the body forced to settle on metrics that do not embarrass or expose certain vendors. The Grid’s answer to this is that its constitution has been designed with checks and balances that will eliminate any possibility of political de-railment (where have we heard that before?) and that it will also be recruiting customers or end-users as Grid members.

Suppliers already detail the power consumption and heat generation of their products. But Grid board member and HP employee Roger Tipley said that these numbers are not useful, because they represent power consumption at full-tilt, 100% workloads that are never seen in real use, and very conservative over-estimates of heat generation.

They’re wildly high. If you based your data center calculations on those numbers, you’d only be able to get about half your gear into the data center, he said.

Neither can the specification numbers be used to compare one product to another, because they do not give even a rough indication of how much power will be consumed or heat generated at real-world part-loads, Tipley said.

We’ve seen one box that didn’t reduce power consumption at all [when the load was reduced from 100%] and another that did, very well, he said.

The US government’s Environmental Protection Agency’s Energy Star scheme only provides a yes or no, pass or fail rating of IT hardware, and does not cover non-desktop servers. Any future effort by the EPA to create more sophisticated standards is bound to see the agency consult the IT industry, and as such the efforts of the Grid to establish standards can be seen as simply anticipating that situation.