Oct. 11, 2007 IBM has launched a program that shows mainframe customers precisely how much energy their machines consume for work actually performed.

The new metering system calculates a machine's watts per hour similar to automobile miles per gallon estimates or appliance kilowatt per year ratings. These power statistics, which can either be observed in real-time or summarized to establish long-term trends, enable customers determine their exact cost savings from energy efficiency programs.

To help customers with future planning, IBM also released a Power Estimator Tool that calculates how any changes in system configurations and workloads might affect a user's entire energy "envelope," including the power needed to both run and cool the machines.

IBM says it will also begin publishing energy consumption data for its System z9 mainframe, derived from field measurements of about 1,000 customer machines. Data collected for August and September show that energy use typically averages at 60% of the maximum, or "label," rating for the z9.

"The mainframe's high utilization rates and extreme virtualization capability may help make it a more energy-efficient choice for large enterprises," says David Anderson, a green consultant for IBM. "A single mainframe running Linux may be able to perform the same amount of work as approximately 250 x86 processors while using as little as 2% to 10% of the amount of energy."

The mainframe metering program is a project of Big Green, IBM's $1 billion investment in improving the efficiency of its products. The initiative recently netted the Green IT Initiative of the Year award from CNET.