This article was originally published in the September/October 1994 issue of Home Energy Magazine. Some formatting inconsistencies may be evident in older archive content.



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Home Energy Magazine Online September/October 1994

Energy Star Insomniacs

The U.S. Environmental Protection Agency (EPA) introduced the Energy Star program last year in an effort to encourage computer manufacturers to add energy-saving features to their products. The features act something like a screen saver, putting equipment to sleep when it's not actually being used. The monitor shuts off and the hard disk drive spins down, then the computer wakes up at the touch of a key, with open documents intact.

Even if it sports the whimsical Energy Star logo, however, the new computer won't save energy as it is supposed to unless the energy-saving feature is activated. Many participating manufacturers are shipping their products with the sleep feature turned off, and the products vary widely in how easy it is for the user to activate it.

The EPA started planning the Energy Star program in 1992, inviting computer industry input to ensure that the program's parameters were realistic. The voluntary, market-based program was introduced officially in June, 1993 and has since enlisted 299 computer and monitor manufacturers, and 43 printer manufacturers, representing a total of more than 2,000 products. At this point, it's impossible to tell how many products on the program's list are shipped with their energy-saving features activated because the agency only recently started tracking that statistic.

Energy Star program manager Linda Latham is working with manufacturers to address this glitch. It's a process of educating both manufacturers and the consumers. Latham says that manufacturers are concerned that many personal computer users never read the manuals, and will freak out when their expensive new machine blanks out the first time, leading to calls for technical support which cost the manufacturer time and money. Government agencies--which purchase more computers then anybody else in the world--already require that computer products arrive with the energy-saving feature activated, and an EPA Energy Star brochure suggests that individual purchasers make the same request.

While the major computer manufacturers expect to eventually ship their products with the features turned on, they don't want to do so before they, and the computer-buying public, are ready. It's a little unnerving at first, says David Lear, environmental program manager for Compaq Computer Corporation, of his own introduction to the feature on a notebook computer. You have to educate the user. There are a thousand things going on when he turns on the computer.

We've gone above and beyond to make it as easy as possible for the customer to access the Energy Star feature, Lear says. Compaq's Energy Star machines start-up the first time with the Compaq Welcome Center, which includes an icon that lets the user activate the power-management feature. Lear, who claims to know his way around computers, says he recently made a trip to his neighborhood electronics superstore to check out the competition, and could figure out how to access Energy Star only on the Compaq models. The company offers 26 models, 19 of which qualify for Energy Star. The other seven also offer power management features, but these bigger models can't power down below the 30-watt program requirement. He adds that the machines can wake up to accept or send faxes in the middle of the night, and are so smart that they turn the monitor on only when there is action on the keyboard.

Jackie Streeter, senior director of engineering interface and design at Apple Computer, says that all of her company's products offer the Energy Star energy-saving feature. Apple is shipping all of its products with the features turned off, but Streeter says the feature is easily accessed through an Energy Star icon in the control panel, a feature found under the Apple icon on the screen. We wanted to make the features voluntary, says Streeter, who foresees manufacturers eventually agreeing to ship with the feature on.

The Energy Star feature saves a considerable amount of energy. A typical setup consisting of a personal computer, monitor, and printer, might draw about 150-250 watts of power and consume about 700-1,000 kWh of electricity annually. Of this, the computer, monitor, and printer typically consume roughly one-third each. A computer is inactive most of the time it is running. Inside the computer, the major power consumers are the disk drives, power supply, processors, and memory. There's a widespread misconception that frequently turning computers off shortens their life. It is also untrue that screen savers save significant amounts of electricity. In fact, equipment life may be extended with less on-time. The EPA estimates that the Energy-Star feature may save as much as $2 billion annually.

According to Philippe Lapujude, a Florida Solar Energy Center (FSEC) research engineer, studies and educated estimates indicate that 20%-40% of the nation's 30-35 million personal computers are left running at night and on weekends. (This is more often the case in offices than in homes.) A National Resource Council of Canada study of 94 computer systems concluded that computer energy consumption could be reduced by 58% if the machines were switched off after 60 minutes of inactivity.

Lapujade monitored the performance of an Energy Star computer, monitor and printer for 86 days, after collecting identical measurements on a standard and comparable 486 system. He measured power demand in watts, power factor for the whole system, and power demand for the laser printer, every 15 minutes. Power factor was low, at around 0.66 for both the Energy Star and the non-Energy Star units (only the computer and monitor were measured). However, power quality dropped to 0.60 when the energy-saving feature was activated. Power demand was 120 watts for a standard computer and monitor, compared to an Energy Star setup in active mode. However, when in sleep mode, the Energy Star computer and monitor drew less than 30 watts.

Lapujade's measurements show that the standard computer system (computer, printer and monitor) used about 470 kWh/year, compared to an estimated consumption of 350 kWh/year for the Energy Star system. The Energy Star system used 26% less energy during the test period, as compared to the standard system, saving 120 kWh per year, or $12.00 (at a cost of 10cents/kWh). The bulk of these savings came from the printer, which saved 80 kWh and $8.00, or 38% of the standard setup's energy use. The computer and monitor cut consumption by only 40 kWh, and saved $4.00, for 17% savings compared to the standard computer. Of course, they turn off their computers at night at FSEC, and Lapujade points out that these savings estimates are conservative for computers that are used less responsibly.

Dariush Arasteh, a researcher in the windows and daylighting group at Lawrence Berkeley Laboratory (LBL), recently acquired an AST computer that arrived with its energy-saving feature turned off. After a little snooping, I figured it out, but only because I was curious, says Arasteh. I would estimate that less than 5% of users would figure it out. Turning the feature on was simple, but not obvious, and it was not documented on paper.

The computer always falls asleep on me, and takes 5 seconds to wake up, says Arasteh. I should really turn it off. Arasteh says the computer's logic is based on hard disk access time and the sleep mode is set to ten minutes. If he does not use the hard disk (either because he is not using the program or because what's in memory is sufficient), the computer falls asleep after ten minutes. If you're typing for ten minutes, the hard disk goes into sleep mode. At minute 11, if you want to save, spell check, or whatever, the hard disk is asleep.

Two computer configurations can hinder proper operation of Energy Star power-management features. Some users have reported that power-management settings configured with Microsoft Windows are lost each time the system is turned on. According to Mary Ann Piette, a staff scientist in LBL's Energy Analysis Program, users can configure the power management through their computer's BIOS set-up to overcome this problem. Future versions of the Windows program should be improved, and not all Windows users have had this problem.

There have also been snags with local area network (LAN) configurations. Many personal computers connected to LAN systems don't power down--the energy-saving feature does not get activated. Network servers typically poll each personal computer every 1 to 5 minutes, which may prevent power management from occurring. (The opposite problem may also occur: the computer may go to sleep, killing the connection to the LAN.)

Piette says one way to overcome this hindrance is to instruct the LAN server to poll only at specified periods during the day, allowing power management to occur during other periods. A second strategy to achieve power management while LAN-connected is to use a network card that stays active even when power management functions are in effect, she says.

The EPA's Latham has been pestering and prodding the reluctant manufacturers to ship the computers with the energy savers switched on, and expects most to make the necessary changes to their assembly lines to do so. She believes that, within a few years, everybody will know--well, of course your computer will go to sleep.

-- Abba Anderson

Abba Anderson, formerly Home Energy's associate editor, is a freelance writer based in Forestville, California.

Further Reading

Power to the PC, PC Magazine, April 26, '94, p.114. PC Magazine, One Park Avenue, New York, NY 10016-5802. Tel: (212)503-5255.

Lean Green Windows Machines,

Windows Magazine, May '94, p.206. Windows Magazine, One Jericho Plaza, Jericho, NY 11753. Tel: (516)733-8300.

Green PCs, InfoWorld, January 26,

'94, p.64. Infoworld Publishing Co., 155 Bovet Road, Suite 800, San Mateo, CA 94402. Tel: (415)572--7341.


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