Confusion may exist about power supplies covered under federal EISA Act

I heard from a major power supply vendor that some of its customers believe that the Energy Independence and Security Act (EISA) of 2007 applies to any single output power that provides 250-watts or less of output power. These customers understand the Act as covering "DIN Mount" or "any single-output" enclosed power supply (that is, used for industrial or commercial applications).

Nope, the Act just covers external “wall-wart” type power supplies.

It’s possible that the federal act, which is written in legalese, might be a bit confusing. Better the legal beagles should have followed the example set by the EnergyStar folks, who wrote a very clear description and gave examples of the type of power supplies covered as “external”:

From the EnergyStar website
External Power Supplies
This web site offers information on the continued development of the external power supply specification and test procedure.

About External Power Supplies 

External power supplies are devices that convert ac power from a wall outlet into lower voltage dc or ac power to be used directly by electronic circuits. External power supplies come in a separate physical enclosure than the end-use product, and usually provide power to the device directly through a separate cord and plug. External power supplies are used to power a variety of electronic devices, including: laptop computers, printers, cordless phones, cell phones, etc.

More than 1 billion external power supplies are shipped per year, and the average American home has five to ten of these components powering devices in their homes. Despite the prevalence and importance of external power supplies, their energy efficiency can often be very low. EPA’s research has indicated that approximately one-third to one-half of the electricity that flows through power supplies is consumed in the power supply itself, as these power supplies are only about 50% to 70% efficient. ENERGY STAR has developed this new program in order to encourage the use of more efficient external power supplies in the market. 

External Power Adapters 


What is an Adapter and Why are they Important?

External power adapters, also known as power supplies, are crucial to the operation of virtually all small electronic devices. As many as 1.5 billion are in use in the U.S. — that’s about five for every person. The total electricity flowing through all types of power supplies is about:

• 300 billion kWh/year, and
• 11% of the national electric bill

They convert high voltage ac electricity from the wall outlet to the low voltage dc power used to power electronic products, like MP3 players, Personal Digital Assistants (PDAs), camcorders, digital cameras, laptops, and cordless and mobile phones.

Earning the ENERGY STAR

An adapter that has earned the ENERGY STAR meets strict energy-efficiency guidelines set by the US Environmental Protection Agency (EPA) and the US Department of Energy (DOE).

• On average, 30% more efficient than conventional models.
• Are often lighter and smaller in size, which makes it easier for consumers to transport products like laptops.

Consumers are now able to purchase a growing variety of products that are packaged with ENERGY STAR qualified power adapters. Products with qualified adapters are identified with a special version of the ENERGY STAR label.