A consortium of IT industry suppliers and users has formed with commendable speed and intends to cause nothing short of a revolution in datacentre, design, operation and management so as to radically increase the power efficiency of datacentres. The Green Grid has formed in response to several realisations about datacentre power:-

Datacentre power problems

1. Power costs are rising. An IBM source said commercial power costs had risen 30 percent in the last five years in the UK. The era of cheap power is over.
2. Urban datacentres are increasingly running up against power-delivery limitations. Some have already found, and more will find, that they simply can't plug in any more equipment in datacentres.
3. The power that is consumed by large datacentres is huge, and said to be equivalent to the power used by the entire city of Leicester.
4. This power is generally dirty, in that its generation causes Carbon Dioxide (CO2) emissions into the atmosphere and thus contribute, it is generally agreed, to global warming.
5. Consolidated servers - virtual servers, blades, virtual blade servers - and consolidated storage packs a lot of power-consuming devices into datacentres, increasing power demand both for running the kit and cooling it.

A Gartner research VP, Michael Bell, said: "It's now possible to pack racks with equipment requiring 30,000 watts per rack or more in connected load. This compares to only 2,000 to 3,000 watts per rack a few years ago."

The era of cheap power is closing and the prospects of simply bringing more power into any given datacentre remote. So datacentre owners, in order to cope with this situation, need to be able to see what power is being used by devices in the datacentre, to measure it, and to improve its utilisation, avoiding where possible power waste. The Green Grid has been formed to help this happen.

Its members include AMD, APC, Dell, HP, IBM, Intel, Microsoft, Sun, VMware and others. They all agree that standard measures and standards themselves are needed in this area and, further, that they have to co-ordinate their efforts if they are to be formed.

Its aims include the definition of sensible models and measures for power efficiency, measurement methods, processes and technologies to improve power-efficiency in IT devices and processes, and the promotion of standards for efficient power use by datacentres and their devices.

Datacentre power consumption characteristics

The power that comes into a datacentre feeds both IT and non-IT equipment: air-conditioning, lighting, chillers, transformers, uninterruptible power supplies (UPS), etc. If IT equipment ran cooler less power would be needed for datacentre cooling. Much power is lost through inefficient cables and computer power supplies.

Gartner research VP Rakesh Kumar reckons that up to 60 percent of the power needed by cooling equipment is wasted. The power supply units used by computers are inefficient; efficient ones costing more and server acquisition prices needing to be low - until now. The total cost of ownership (TCO) of IT equipment is going to come to the fore as IT buyers get datacentre power usage and cost awareness.

Typical power supplies waste 30-35 percent of the input power. Better, and pricier, ones lose only 10 percent or less. A background problem here is that the IT department generally doesn't pay the business' electricity bill and datacentre power costs are not broken out in that bill.

Even if these power costs were known there is a lack of ability to measure individual device power use and efficiency and to compare overall datacentre power efficiencies between businesses to arrive at benchmarks for best practise.

Datacentre power efficiency metrics

The Green Grid believes that tools to measure and improve datacentre power efficiencies with performance and energy metrics are very much needed. This means device-level instrumentation so that measures can be made of power in, work output, and power loss.

There needs to be a standard set of datacentre performance and energy efficiency metrics, comparable to a road vehicle's miles-per-gallon metric. These metrics must start at the electricity inlet supply to the datacentre and include all datacentre electricity use, including lighting, air-conditioning, UPS', etc as well as actual computing equipment.

The near-term aim of having the metrics is threefold:-

1. Minimise datacentre power requirement
2. Maximise the use of the incoming power for direct IT work and
3. Minimise the power needed for non-IT work.

The longer term aim of the Green Grid is to create a power-efficiency roadmap for the datacentre to guide CIOs along a road of continuous improvement. This will entail the provision of datacentre instrumentation and control devices to measure, monitor and manage datacentre power efficiency and optimise it.

It will be a difficult and problematic multi-year effort. Fortunately every organisation involved in the Green Grid has a datacentre and is suffering the same type of problems with regard to power as everybody else. For those members involved in supplying datacentre equipment the involvement of user organisations should provide a good reality check to prevent a focus on partial solutions.

Both these factors indicate that the Green Grid, unlike other cross-industry standards bodies, may produce the goods in short order from a unified body and not result in damaged and impractical standards such as those associated with the various Unix standardisation projects in the past.

Let us sincerely hope so; the stakes are a little higher this time around.