IBM is investing a billion dollars a year in an initiative to double energy efficiency, first in its own data centres, then in those of its customers.

Around half of computer hardware running costs are down to energy and that's expected to rise to around 70 percent by 2011 unless checked. In data centres, the power goes to servers, network gear, spinning disk drives and operating tape automation devices. Yet more power is needed to cool this equipment and prevent it overheating. The development and use of blade servers is exacerbating the server energy consumption and cooling problem. The continuing rise in unstructured data, and of disk-based virtual tape libraries, both increase storage energy and cooling needs.

IBM has in excess of 8 million square feet of data centre space worldwide. It both operates and builds data centres for clients - for instance designing 20 data centres in China alone, during 2006.

Its green make-over involves:

• Greater use of virtual servers to make the hardware do more with no increase in energy consumption,
• Automatically switching servers to a power-saving standby state when not in use,
• Only switching on cooling when it's needed,
• Using the heat from liquid-cooled kit to generate power and store it for use later, and
• Use of thermal engineering and 3D modelling to optimize cooling data centre air-flow

IBM aims to double its data centre computing capacity by the end of 2010 without increasing energy use. This is equivalent to saving 5 billion kilowatt-hours per year.

Forrester Research analyst Christopher Mines said this was more than just selling more efficient processing chips and servers. The technologies IBM is developing can be retrofitted to existing data centres so that they can do the same amount of work using less energy.

Other green initiatives

Sun has committed to reduce greenhouse gas emissions 20 percent by 2012 from 2002 levels. It is also presenting its Project Blackbox, a data centre in a shipping container, as a more energy-efficient data centre.

HP has said it will cut its energy use 20 percent by 2010. It believes it can make itself more energy-efficient by consolidating its data centres world-wide to just three in the US. The company is working on ways to tune data centre cooling so that only hot spots are cooled and less energy is needed to drive data centre air-conditioning systems.

Many suppliers are joining the Green Grid consortium, which is working on standards for energy consumption by data centre gear. Members include AMD, Dell, HP, IBM, Intel, Sun and EMC/VMware.

In December, 2006, Congress passed Senate Bill 3684, looking at data centre power consumption. It authorizes the Environmental Protection Agency to encourage the use of energy efficient servers and study energy usage.