ENERGY STAR EPS Version 2.0 Specification Finalized

Version 2.0 of ENERGY STAR’s External Power Supply efficiency specification has been finalized and will take effect on November 1, 2008. Notable changes in the version 2.0 of the specification include:

  • Increased active mode energy efficiency minimum requirements
  • Reduced no-load power max limits
  • Power factor correction requirement added for power supplies with an input power ≥ 100 watts
  • Separate no-load requirements for AC-DC and AC-AC

The test methodology is unchanged, and compliance is voluntary The following tables show active mode energy efficiency and no-load power consumption specifications in the final draft.

EPS Active Mode Efficiency: Standard Models

Nameplate Output Power (Pno) Minimum Average Efficiency in Active Mode (expressed as a decimal, rounded to hundreths)
0 to ≤ 1 watt ≥ 0.480 * Pno+ 0.140
> 1 watt to ≤ 49 watts ≥ [0.0626 * Ln (Pno)] + 0.622
> 49 watts ≥ 0.870

EPS Active Mode Efficiency: Low Voltage* Models

Nameplate Output Power (Pno) Minimum Average Efficiency in Active Mode (expressed as a decimal, rounded to hundreths)
0 to ≤ 1 watt ≥ 0.497 * Pno+ 0.067
> 1 watt to ≤ 49 watts ≥ [0.0750 * Ln (Pno)] + 0.561
> 49 watts ≥ 0.860

* A low voltage model is an EPS with a nameplate output voltage of less than 6 volts and a nameplate output current greater than or equal to 550 milliamps

No-load Energy Consumption

Nameplate Output Power (Pno)Maximum Power for No-load
AC-AC EPSAC-DC EPS
0 to < 50 watts ≤ 0.5 watts ≤ 0.3 watts
≥ 50 to ≤ 250 watts ≤ 0.5 watts ≤ 0.5 watts

Conforming Design Ideas from Power Integrations

The following table shows Power Integrations Design Ideas that meet the spec.

DocumentDevice
Used
Power Output (W)Efficiency
(4 Points
Average) *
CEC
2008 †
ENERGY
STAR 2.0 ‡
DI-113TNY274PN571.5%59.9%68%
DI-115TNY376PN7.5 / 13 Pk77.7%68.1%75%
DI-143TOP258MN20 / 80 Pk85%77%81%
DI-144TOP258PN50 / 70 Pk89.9%84%87%

* The actual measurement of the average efficiency of the design idea at the 4 test points of load: 25%, 50%, 75% and 100%, as called for by CEC and ENERGY STAR specs

† The California Energy Commission standard that will become effective in July, 2008

‡ Minimum average efficiency called for by EPS V. 2.0 spec

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