Green PC

This is a general term for features that reduce the growing environmental impact of the manufacture or use of comput-ers. This impact has several aspects: energy consumption, resource consumption, e-waste, and pollution and green-house emissions.

Energy Consumption

The greatest part of a typical computer system’s power con-sumption is from the monitor, followed by the hard drive and CPU. It follows that considerable energy can be saved if these components are powered down when not in use. On the other hand, most users do not want to go through the whole computer startup process several times a day. One solution is to design a computer system so that it turns off many components when not in use but is still able to restore full function in a few seconds.

When applied to a personal computer, the federally adopted Energy Star designation indicates a computer sys-tem that includes an energy saving mode that can power down the monitor, hard drive, or CPU after a specified period elapses without user activity, such that the inactive system consumes no more than 30 watts. In the ultimate energy-saving feature a suspend mode saves the current state of the computer’s memory (and thus of program opera-tion) to a disk file. When the user presses a key (or moves the mouse), the computer “wakes up” and reloads its mem-ory contents from the disk, resuming operation where it left off. By 2000, virtually all new PCs were Energy Star compli-ant, though many users fail to actually enable the power-saving features.

In July 2007 stricter Energy Star specifications for desk-top PCs were adopted. Power supplies must now be at least 80 percent efficient. Meanwhile, the International Energy Agency has been promoting an initiative to reduce power consumption of idle PCs (and other appliances) to 1 watt or less.

Resource Consumption

Computers consume a variety of resources, starting with their manufacturing and packaging. Resource consumption can be reduced by building more compact units and by designing components so they can be more readily stripped and recycled or reused. Adopting reusable storage media (such as rewrit-able CDs), recycling printer toner cartridges, and changing office procedures to minimize the generation of paper docu-ments are also ways to reduce resource consumption.

E-Waste

In recent years the disposal of obsolete computers and other electronic equipment (“e-waste”) has been both a grow-ing concern and a business opportunity. There are many toxic substances in electronics components, including lead, mercury, and cadmium. Processing e-waste to recover raw materials is expensive, so greater emphasis has been placed on disassembling machines and reusing or refurbishing their individual components. Meanwhile, many communi-ties have banned disposing of e-waste in regular trash, and some have offered opportunities to drop off e-waste at no or minimal charge. States such as California have also insti-tuted a recycling fee that is collected upon sale of devices such as CRT monitors and televisions.

Pollution and Greenhouse Emissions

Fabrication of computer chips in more than 200 large plants around the world involves a variety of toxic chemicals and waste products. The Silicon Valley alone is home to 29 toxic sites under the EPA’s Superfund Program. The shift of much of semiconductor and computer component manufacturing to countries such as China that have less strict pollution controls has also exacerbated what has become a global problem.

Whether through regulation or enlightened self-interest, companies that want to reduce future emissions can use several strategies. Manufacturing equipment and processes can be modified so they create fewer toxic substances or at least keep them from getting into the environment. Non-toxic (or less toxic) materials can be substituted where possible—for example, use of ozone-depleting chlorofluo-rocarbons (CFCs) as cleaning agents has been largely elimi-nated. Finally, waste can be properly sorted and disposed of, and recycled wherever feasible.

Like other major manufacturing sectors, the computer industry is also faced with the need to reduce the amount of the greenhouse gases (particularly CO2) contributing to global warming. This mainly means further reducing the energy consumption of new PCs. In June 2007 a number of major players, including Google, Intel, Dell, Hewlett-Packard, Microsoft, and Sun, established the Climate Savers Computing Initiative. Going beyond Energy Star, the pro-gram is expected to reduce power consumption equivalent to 54 million tons of greenhouse gases annually—about the same as that produced by 11 million cars or 20 large coal-fired power plants.