Which energy-efficiency rules apply to chargers in the US?

Main answer · Wecent Editorial Team

Short answer: Most chargers sold in the US are external power supplies (EPS) under the Department of Energy’s energy conservation standards in 10 CFR Part 430. Since 10 February 2016, Level VI efficiency and no-load limits apply to direct-operation EPS. Products must be tested under DOE’s test procedure, certified by the manufacturer or importer in DOE’s Compliance Certification Management System (CCMS), and the nameplate typically shows the Roman numeral VI. California also has its own appliance efficiency regulations and database. Confirm the details with your test lab.

What DOE regulates

DOE sets minimum average active-mode efficiency and maximum no-load power for external power supplies, based on output power and type. Level VI, which took effect on 10 February 2016, is the current federal level for direct-operation EPS. Some product types, such as certain battery chargers, fall under separate battery charger standards.

Testing

Testing follows DOE’s test procedure in Appendix Z to Subpart B of 10 CFR Part 430. For adaptive power supplies such as USB PD chargers, which can output several voltages, the procedure specifies how to test at the relevant output points. Your lab should test according to the current version of the procedure.

Certification

Before distributing a covered product, the manufacturer (which includes importers under DOE rules) must submit a certification report through DOE’s Compliance Certification Management System (CCMS). The model then appears in DOE’s public database. Retailers may check this.

Marking

EPS nameplates use the international efficiency marking protocol; Level VI products carry the Roman numeral “VI”. This marking is commonly checked by customs, retailers and marketplaces.

California

California’s Title 20 appliance efficiency regulations also cover some products and have their own certification database (MAEDbS). Requirements can differ, especially for battery chargers. Check whether your products need listing there.

How this relates to the EU

EU Ecodesign Regulation (EU) 2019/1782 and DOE Level VI are similar in purpose and limits but are separate legal regimes with their own test conditions, documentation and certification. EU test reports don’t automatically satisfy DOE certification.

Documents to request

1. DOE efficiency test report for the exact model and voltage outputs.
2. Evidence of DOE certification or data for you to certify as importer.
3. Nameplate artwork showing the VI marking.

Confirm with Wecent which US efficiency data they hold for each model, and check current DOE requirements on the DOE website or eCFR before shipping.

Where this answer says confirm with Wecent, the detail is not published on the product page and has to come from the datasheet or the factory. General facts come from the standards bodies, regulators or device makers named in the text.