Businesses and home users can help the environment and save money at the same time by making better use of basic tools for desktop PC power management.

It's a simple message but one that's sometimes hard to get across, especially to home users who don't realize how much electricity their computers waste if they don't take steps to manage consumption, said Mark Bramfitt, head of the consumer energy efficiency group at Pacific Gas & Electric, a California utility.

Power management tools ship with virtually all computers these days but the U.S. Environmental Protection Agency reckons that most home users turn them off within a few months of buying a PC, Bramfitt said.

"There's a tremendous opportunity for energy efficiency and environmental improvements, but influencing individual PC users is a very difficult thing to do," he said at an energy efficiency seminar arranged by the Business Council on Climate Change.

The management tools can yield annual energy savings of $25 to $30 per desktop computer, according to Bramfitt. For big companies that operate thousands of PCs that quickly adds up to a lot of money.

The tools allow the computer to turn off the processor and hard drive after they have been idle for, say, 15 minutes, and put the whole computer into standby after 30 minutes. That reduces the energy consumed by a PC from roughly 100 watts to 40 watts with the power tools enabled, Bramfitt said.

To enforce power management, companies can use network-based tools that allow the settings on a PC to be controlled centrally. PG&E and other utilities give rebates to companies that use these tools because it helps them to avoid having to construct new power plants.

The tools, from companies like Faronics, Scriplogic and Veridiem, range in price from $15 to $20 per computer, said Alena Gilchrist [cq], a senior project manager with the City of San Francisco's SF Environment group. PG&E will subsidize the cost to the tune of $15 per PC for businesses, and the City of San Francisco gives slightly more.

PC makers could do more to help. Around half of the energy PCs consume is sucked up by inefficient power supplies, Bramfitt said. More efficient supplies are available but cost about $20, compared to $5 for the cheap ones, so PC makers don't use them.

Much of the wasted energy pours out as heat, which adds to air conditioning bills. "The PC that sits under your desk at home or in the office kinda looks like a toaster to PG&E," he said. "Half the energy that goes into it comes out as heat."