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Energy Star and the PC

What Does Enery Star Mean On a PC?


ENERGY STAR was a program that was first developed back in 1992 by the US Environmental Protection Agency as a voluntary labeling program. Essentially, products that met a specific power criteria could display the logo as a means inform consumers they were more energy efficient than the traditional product. They first began this labeling with personal computer products that tended to be left on at all times by corporations.

In 1995 the program expanded beyond computers to include other consumer electronics and appliances. The next year, the US Department of Energy became involved in the program for specific product categories. Most people are probably familiar of ENERGY STAR because this partnership brought the yellow energy guide labels to home appliances such as washers, dryers, refrigerators and dish washers.

Why Does it Matter?

Personal computers and home electronics may seem like they don't use a lot of power, but unlike a light that is switched off when not in use, most people leave their computers turned on. The combined effect of millions of personal computers even in standby mode can use a fair amount of power. All of this power usage translates into greenhouse gases from the various sources used to generate the electricity. By creating a system that promotes power efficiencies, consumers can help to reduce the amount of electricity consumed thus reducing greenhouse gases and cost savings for the consumer.

New Qualifications For PCs

As technology has changed over the years, the ENERGY STAR program has updated the requirements for the ENERGY STAR program. After all, a PC built four years ago is going to have very different power requirements from systems today that use multiple processor cores and feature a greater number of integrated devices. As a result, a new 4.0 specification was created for computer systems effective July 20, 2007. The new specifications set three new requirements that all new computers must meet to display the logo.

The first and probably the most important of the changes is in power supply efficiency. Computer components run at lower voltages then those provided by an outlet. To do this, a power supply converts the voltages down to those the computer can use. During this process, some of the energy is lost as thermal heat. The more efficient the power supply is, the less power is lost as heat. For example, a 65% efficient power supply would convert 100W of wall current to 65W of power for the internal components. The new ENERGY STAR requirements are that all internal and external power supplies must have a minimum efficiency rating of 80% across all rated output. This is a very significant change.

The second change is what they call “Operational Mode Efficiency” requirements. Essentially this defines how much power a desktop or notebook computer can use when it is in standby, sleep and idle modes of operation. The amount of power for the standby and sleep are set at specific levels no matter what the notebook or desktop hardware is. Idle power levels can vary depending upon the hardware that is inside the PC.

To give a better example of this, a desktop computer system is allowed a maximum of 2W while in standby and 4W when in sleep modes. A basic desktop is allowed to use up to 50W when in idle while a multiple core desktop with dedicated graphics card can use up to 95W. Notebooks are even lower with 1W for standby, 1.7W for sleep and either 14 or 22W for idle.

The final change is for a power management requirement. Users may be somewhat familiar with this settings in Windows control panels that can adjust the delays between sleep and standby for the monitor, drives and the whole system after it has no user interactivity. New computers must have a power management setting of 15 minutes to put the monitor into a sleep mode and a 30 minute setting to put the entire computer into sleep mode. Of course, these are only requirements for the settings when the computer is shipped and they can be changed by the user after they receive the PC.

What Consumers Can Do

The total cost of ownership for a computer is more than just the cost of the computer system. Consumers also pay for the power to run their computers. Then there are other factors to the use of a computer such as the resources made to produce the computer and the cost of properly disposing of the computer. The ENERGY STAR program can help let consumers know that they are taking a step at reducing some of the costs of ownership by reducing the power usage and also helping to save the environment by reducing power generation.

When purchasing your next computer system, look for the ENERGY STAR logo either on the packaging or materials for the PC. If they are displayed with the computer system, then you know that the computer meets the minimum requirements to earn that logo and will typically use less power than one that does not have the logo.

If you already have a computer system and are not looking to replace it, you can still help reduce the power consumption by adjusting your usage patterns and changing the Power Management settings in the operating systems. By helping to reduce the power used by the system when it is idle, you can also help save on power bills and the environment.

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