Efficiency of Power Supplies in the Active Mode
Power supplies are one of the crucial building blocks of a modern society, converting high-voltage alternating current (AC) into low-voltage direct current (DC) for use by the electronic circuits in office equipment, telecommunications, and consumer electronics. Over 2.5 billion AC/DC power supplies are currently in use in the United States alone. About 6 to 10 billion are in use worldwide.
While the best power supplies are more than 90% efficient, some are only 20 to 40% efficient, wasting the majority of the electricity that passes through them. As a result, today’s power supplies consume at least 2% of all U.S. electricity production. More efficient power supply designs could cut that usage in half, saving nearly $3 billion and about 24 million tons of carbon dioxide emissions per year. If you are looking to purchase some, here is an electronics voucher to save on your new power supplies.
The Purpose of This Web Site
This Web site was created by EPRI and Ecova to initiate a global dialogue about energy efficient power supplies. Our focus here is particularly on the issue of energy consumption in the active or “on” mode of product operation. According to our research so far, nearly 75% of all the energy used by power supplies occurs in active mode. For those interested primarily in standby power consumption or other low-power modes, please visit Lawrence Berkeley National Laboratory’s Web site on that topic at http://standby.lbl.gov.
In 2003, the California Energy Commission’s PIER (Public Interest Energy Research) program has funded Ecova and EPRI to assess the efficiencies of modern power supplies and recommend strategies for improving them. An open exchange of design information, test methods, measured results, and other related documents is essential to that project’s success, tapping the best information available from manufacturers, government agencies, utilities, and product users.
Ecova and EPRI continue to work on a variety of other power supply and whole-product efficiency initiatives in the U.S., Europe, and Asia, described in more detail under Projects and at www.efficientproducts.org website. Our goal in every case is to accelerate the market for more energy-efficient products, saving energy and preventing pollution.
How You Can Get Involved
- Power supply manufacturers: Review and comment on the proposed test methods, browse efficiency test reports on power supplies, read about the design competition held in 2004, and contribute news clips on your latest efficient product offerings.
- Electronics assemblers: Compare the efficiency of the power supplies you use to the models in our test reports.
- Utilities: Join our efforts in improving efficiency of power supplies, find out how utilities participate in the 80Plus Program and try the calculators to see how much energy a more efficient power supply will save.
- Government agencies: Check efficiency policies for the latest news on labeling and incentive programs, procurement strategies, and mandatory standards.
- Consumers: Take a look at the Efficiency Opportunities and the Power Supply Efficiency Policies to learn more about the developments that are happening in the power supply efficiency research.