Greent IT is not just about making data centers run more efficiently (see Businesses Riding First Wave of Green IT). Reducing PCs' power use an also have a huge impact on a company's electric bill.

As much as 55 percent of IT power consumption could come from peripherals and PCs, according to a new study by Forrester Research. And with the recession now underway, cutting IT power costs is no longer an issue for only the facilities staff, but also for the CIO. 

That is the message from Forrester Research's Doug Washburn, the lead analyst on the report.

Thus far the most common way of cutting PC power costs has been asking employees to turn their computers off, Washburn told eWeek.com. More than half of the 91 IT professionals in the Forrester study rely on this method. 

But now the interest for more sophisticated products, like fee-based power management software is increasing, he said. Power management software is used to control and monitor the electrical use of PCs and peripherals. It could put the machine in a low-power state when inactive, for example. It can also reduce cooling requirements, prolong battery life for portable devices and by this reduce operation costs and environmental effects.

The Forrester study shows that 7 percent of responding companies already use fee-based power software, but 20 percent are evaluating products and 37 percent would consider it. And today's methods for cost control among IT departments are not always smart and strategic, so there is room for improvements. 

"When we asked how they're doing it, it's very much being done on an ad hoc basis," said Washburn. 

If power-savings chips and software were hot technologies for greentech VCs before, now there are even more opportunities (see How Many PCs to a Global Brownout). 

And the beneficiaries could be companies like Verdiem with its Surveyor software and Powervation with its Auto-Control technology.

 According to an earlier estimate by Gartner, there will be 2 billion PCs in use by 2014 which will double the number of PCs turned on at the same time in the world.

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