The typical computer consists of a CPU tower, a monitor, a printer and other options devices and is rated at 150 watts. The monitor consumes approximately 75% of this. With computer and Internet use on the rise, more emphasis is being placed on power management and saving energy. As a point of reference, if every computer sold in the United States met ENERGY STAR requirements, the cost savings associated would exceed $2 billion annually and the reduction of greenhouse gas emissions would be the equivalent of removing 2 million cars from the road.
Most computers bought in the past 5 years will have many power saving features built in. These features include standby, active mdoe and sleep mode. These provide energy savings when performing tasks or in standby. Low power or “sleep mode” occurs when a computer has been inactive for a period of time the length of which can be set by the user. When in sleep mode, the hard drive spins slower, which reduces power consumption. Moving the mouse or touching a key will “awake” the computer to resume its use.
Unlike with other household appliances, an ENERGY STAR label will not guarantee you are saving money or energy, as your own usage habits will determine your bills more than the computer itself. In addition, ENERGY STAR options need to be activated after purchasing the computer in order for you to take advantage of the energy saving features.
Generally speaking, in order for a computer to qualify for the ENERGY STAR label, it must use an energy efficient power supply, operate efficiently in Standby/Off, Sleep and Idle modes (see below) and include power management features and education for the user.
The criteria for operating efficiently in the various modes are as follows:
- Consume a maximum of 2 watts in Standby/Off mode
- Consume a maximum of 4 watts in Sleep mode
- Consume a maximum of 50 – 95 watts when idle (depending on the type of CPU)
For energy saving ideas for your computer, see our computer tips sections below.