Big Blue is about to go green. IBM Personal Computer Co. is preparing to introduce a compact computer that addresses key issues of environmental interest -- energy conservation and electromagnetic radiation.
The typical desktop computer uses 250 to 300 watts of power. But IBM's offering belongs to a new generation of computers, popularly called "green PCs," that will cut energy usage to less than 60 watts.
Many of these new computers, as well as printers and monitors, are expected to be introduced next month as part of the Environmental Protection Agency's Energy Star program for encouraging conservation in the PC industry.
In terms of energy costs, IBM Personal Computer's green PC -- it has not been named -- will use about $15 in electricity a year. Conventional office PCs have an annual electric cost of $125 to $150.
"In corporations that have hundreds or even thousands of PCs, the savings in energy costs can be substantial," noted Steven Anzovin, author of "The Green PC" ($9.95, Windcrest McGraw-Hill), a new book of ideas for minimizing the environmental impact of personal computers.
Beyond the power consumption of the computers, "there will also be significantly reduced cooling costs for offices," Mr. Anzovin said. "Conventional computers generate a lot of heat."
And because the green machine does not need an internal cooling fan, as conventional PCs do, it is also quieter.
Whether the energy cost savings will be offset by higher prices for Energy Star products is not certain. When the IBM subsidiary showed its green PC prototype last year, it vowed that there would be no cost penalty for buying green.
Technically, IBM may be able to keep that promise. The computer itself, which is powered by an Intel 486 microprocessor, may not cost more than other PCs using the same chip. But the display is another story. The version shown earlier used an impressive flat-panel, active-matrix color display, the same 10.4-inch screen found on IBM's classy Thinkpad 720C notebook computer. These screens are not cheap.
Another costly feature could arise from the computer's expansion slots. The green PC uses a relatively new technology that requires a plug-in card about the size of a thick credit card, a standard known as PCMCIA (for personal computer memory card industry association). Many of the PCMCIA cards now available are quite expensive.
Companies committed to environmentally friendly policies will find another reason besides costs to consider the green PC. IBM says the active-matrix color screen emits none of the very low frequency and extremely low frequency electromagnetic radiation produced by conventional monitors that use a cathode-ray tube.
Electromagnetic radiation from video display terminals has long been suspected, but never proved, as a possible cause of cancers and other health ailments among PC users.
Still, some people say it is too soon to judge the green PC as risk-free.
"It's certainly not going to have the ELF and VLF fields that come off the deflection coils of the cathode ray tube monitors," said Louis Slesin, editor of the newsletter VDT News in New York.
He added, however: "I'd like to see some measurements. There might be some other electronic mechanism there. I don't want to see a risk under every rock, but I'd like to see some data."
The machine is also likely to gain friends because it is so small and lightweight -- 12 inches square by about 2 inches tall. It can slip neatly into a desk drawer or be tucked on a bookshelf, and including the screen weighs 8 pounds. The main system comes with a bolt to fasten to a desk.
The IBM green PC draws heavily from technologies developed for portable computers. The computer "goes to sleep," for example, after a period of inactivity.
When all its components are in use -- hard disk, floppy disk, keyboard, mouse and processor -- the computer uses just 30 watts of power, and the display 21 watts. At full capacity, it uses less energy than a 60-watt light bulb.
The real savings come when the computer is inactive but still plugged in. According to IBM, a typical end-user duty cycle -- the time a worker actually spends using the computer on the job -- is about 3 hours a day. The rest of the time the computer sits idly, drawing power.
Once it has detected no activity for a certain period, typically 10 minutes but longer at the user's discretion, the green PC begins a gradual drift into sleep.
The PCMCIA cards turn themselves off, and the hard disk and floppy disk stop spinning. Power consumption falls to 16 watts, just enough for the computer to snap back to life when the user touches the keyboard.
The monitor, meanwhile, has four stages of operation. After about 10 minutes of inactivity, the back lighting goes off. Back lighting is a voracious consumer of power, which explains why many notebook and laptop computers run only a couple of hours on a single battery charge. Ceasing the back lighting saves about 10 watts of power. A touch of the space bar brings the screen back instantly.
If the inactivity continues, the monitor drops to the next level, 5 watts, and eventually to 3 watts. In these stages it can take several seconds for the screen to spring back to life. For most users the wait is insignificant.
The screen itself is quite pleasant, unlike some other color liquid-crystal-display panels. It is a VGA-level screen, which means it has 640 dots of resolution horizontally and 480 dots vertically. Windows and other graphical applications are easy to use on the screen, although some larger type sizes are not very crisp.
Earlier this year, IBM exhibited a prototype of a 12-inch active-matrix color screen, a size more suitable to standard business applications. The prototype boasted XGA-2 graphics, with a screen resolution of 1,024 by 768, much sharper than the VGA screen. Color images on this screen approached photographic quality.
IBM may introduce this screen later in the year, but the cost is certain to be much more than conventional color monitors.
An alternative may be "power managed" monitors, which are conventional cathode-ray displays with the added ability to reduce their power consumption when not in use. An IBM researcher said the green PC was designed to work with any power-managed monitor.
In its maximum configuration, the green PC can have a 50-megahertz 486SLC chip, a math co-processor, 16 megabytes of system memory, an internal 120-megabyte hard disk drive, an internal 3.5-inch floppy disk drive and a keyboard with IBM's Trackpoint II pointing device.
The use of PCMCIA cards in a desktop unit is intriguing. The cards can be used for data and facsimile modems, solid-state data storage, network adapters and even miniaturized hard disks with capacities approaching 100 megabytes, all in the credit card size. (One company is experimenting with a miniature PCMCIA video camera, for videoteleconferencing.)
Because many portable computers now come with PCMCIA slots, the slot on the desktop will allow a user to easily take the hard disk from one computer and insert it in another.
(Peter Lewis works out of the New York Times' Austin, Texas, bureau:  328-8258.)