# Are You Ready for Level VII Efficiency?

Electronic engineers, system architects and power designers are under pressure to create advanced products that deliver high levels of functionality and meet demanding performance criteria while keeping energy use as low as possible. This makes sense from the point of view of helping consumers lower their energy bills, but is just as essential when it comes to the environment, contributing to a sustainable future that makes best use of vital resources and minimizes greenhouse gas emissions.

And these requirements are increasingly being built into legislation and standards with which manufacturers of everything from consumer products to industrial systems and from medical devices to office equipment are expected to comply. Among these are the standards for efficiency set by the Department of Energy (DOE) in the United States and reflected in other global standards.

For example, back in 1992 the Environmental Protection Agency initiated a voluntary program to enhance energy efficiency and reduce pollution. This subsequently evolved into Energy Star, a program to help consumers, businesses, and industry save money and protect the environment through the adoption of energy-efficient products and practices. An ENERGY STAR label identifies top-performing, cost-effective products, homes, and buildings. Twelve years after the voluntary program began, regulations were implemented that mandated minimum average efficiency levels and maximum no-load power consumption limits. These DOE standards have become enshrined in legislation such as the Energy Policy and Conservation Act (EPCA) and the Energy Independence and Security Act (EISA).

Under the auspices of these standards the DoE developed an international efficiency marking protocol under which power supplies could be rated based on their efficiency. This mark does not serve as a consumer information label, but rather demonstrates the performance of the power supply when tested to the internationally supported test method (see www.energystar.gov/powersuppliesdevelopment. The international efficiency mark consists of a Roman numeral from I to VII - use of Roman numerals avoids any potential conflict with consumer efficiency labelling schemes - with I being the least stringent (least efficient) level and VII being the highest (most efficient). To date, levels I – VI have been set, with Level VI having gone into effect in 2016.

The requirements for Level VI with respect to minimum active mode average efficiency and no-load maximum power consumption for direct operation single-voltage external power supplies are shown below.

Single-Voltage External AC-DC Power Supply, Basic-Voltage | ||
---|---|---|

Nameplate Output Power (P_{out}) |
Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode (W) |

P_{out} ≤ 1 W |
≥ 0.5 x P_{out} + 0.16 |
≤ 0.100 |

1 W < P_{out} ≤ 49 W |
≥ 0.071 x ln(P_{out}) - 0.0014 x P_{out} + 0.67 |
≤ 0.100 |

49 W < P_{out} ≤ 250 W |
≥ 0.880 | ≤ 0.210 |

P_{out} > 250 W |
≥ 0.875 | ≤ 0.500 |

Single-Voltage External AC-DC Power Supply, Low-Voltage | ||

Nameplate Output Power (P_{out}) |
Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode (W) |

P_{out} ≤ 1 W |
≥ 0.517 x P_{out} + 0.087 |
≤ 0.100 |

1 W < P_{out} ≤ 49 W |
≥ 0.0834 x ln(P_{out}) - 0.0014 x P_{out} + 0.609 |
≤ 0.100 |

49 W < P_{out} ≤ 250 W |
≥ 0.870 | ≤ 0.210 |

P_{out} > 250 W |
≥ 0.875 | ≤ 0.500 |

Single-Voltage External AC-AC Power Supply, Basic-Voltage | ||

Nameplate Output Power (P_{out}) |
Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode (W) |

P_{out} ≤ 1 W |
≥ 0.5 x P_{out} + 0.16 |
≤ 0.210 |

1 W < P_{out} ≤ 49 W |
≥ 0.071 x ln(P_{out}) - 0.0014 x P_{out} + 0.67 |
≤ 0.210 |

49 W < P_{out} ≤ 250 W |
≥ 0.880 | ≤ 0.210 |

P_{out} > 250 W |
≥ 0.875 | ≤ 0.500 |

Single-Voltage External AC-AC Power Supply, Low-Voltage | ||

Nameplate Output Power (P_{out}) |
Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode (W) |

P_{out} ≤ 1 W |
≥ 0.517 x P_{out} + 0.087 |
≤ 0.210 |

1 W < P_{out} ≤ 49 W |
≥ 0.0834 x ln(P_{out}) - 0.0014 x P_{out} + 0.609 |
≤ 0.210 |

49 W < P_{out} ≤ 250 W |
≥ 0.870 | ≤ 0.210 |

P_{out} > 250 W |
≥ 0.875 | ≤ 0.500 |

Multiple-Voltage External Power Supply | ||

Nameplate Output Power (P_{out}) |
Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode (W) |

P_{out} ≤ 1 W |
> 0.497 x P_{out} + 0.067 |
≤ 0.300 |

1 W < P_{out} ≤ 49 W |
≥ 0.075 x ln(P_{out}) + 0.561 |
≤ 0.300 |

P_{out} > 49 W |
≥ 0.860 | ≤ 0.300 |

Level VII - which is going through formal ratification process and will align with other global standards, such as the European CoC Version 5 Tier 2 - will demand even higher efficiency and lower no-load operation. According to Energy Star testing laboratory BACL, these are expected to be as per the following table.

Slngle-Voltage External AC-DC Power Supply, Basic-Voltage | ||
---|---|---|

Nameplate Output Power (Pout) | Minimum Average Efficiency in Active Mode (expressed as a decimal) |
Maximum Power in No-Load Mode [W] |

P_{out} ≤ 1 W |
≥ 0.5 x P_{out} + 0.169 |
≤ 0.075 |

1 W < P_{out} ≤ 49 W |
≥ 0.071 x ln(P_{out}) - 0.00115 x P_{out} + 0.67 |
≤ 0.075 |

49 W < P_{out} ≤ 250 W |
≥ 0.890 | ≤ 0.150 |

P_{out} > 250 W |
≥ 0.890 | ≤ 0.150 |

Slngle-Voltage External AC-DC Power Supply, Low-Voltage | ||

P_{out} ≤ 1 W |
≥0.517 xP_{out} + 0.091 |
≤ 0.075 |

1 W < P_{out} ≤ 49 W |
≥ 0.0834 × ln(P_{out}) - 0.0011x P_{out} + 0.609 |
≤ 0.075 |

49 W < P_{out} ≤ 250 W |
≥ 0.880 | ≤ 0.150 |

P_{out} > 250 W |
≥ 0.880 | ≤ 0.150 |

Slngle-Voltage External AC-AC Power Supply, Basic-Voltage | ||

P_{out} ≤ 1 W |
≥0.5 X P_{out} + 0.169 |
≤ 0.075 |

1 W < P_{out} ≤ 49 W |
≥ 0.0582 x ln(P_{out}) - 0.00104 x P_{out} + 0.727 |
≤ 0.075 |

49 W < P_{out} ≤ 250 W |
≥ 0.902 | ≤ 0.075 |

P_{out} > 250 W |
≥ 0.902 | ≤ 0.200 |

Slngle-Voltage External AC-AC Power Supply, Low-Voltage | ||

P_{out} ≤ 1 W |
≥0.517 x Pout + 0.091 | ≤ 0.072 |

1 W < P_{out} ≤ 49 W |
≥ 0.0834 × ln(P_{out}) - 0.0011x P_{out} + 0.609 |
≤ 0.072 |

49 W < P_{out} ≤ 250 W |
≥ 0.880 | ≤ 0.185 |

P_{out} > 250 W |
≥ 0.880 | ≤ 0.500 |

Multiple-Voltage External Power Supply | ||

P_{out} ≤ 1 W |
≥ 0.497 x P_{out} + 0.067 |
≤ 0.075 |

1 W < P_{out} ≤ 49 W |
≥ 0.0782 × ln(P_{out}) - 0.0013 x P_{out} + 0.643 |
≤ 0.075 |

49 W < P_{out} ≤ 250 W |
≥ 0.885 | ≤ 0.125 |

P_{out} > 250 W |
≥ 0.885 | ≤ 0.125 |

The good news is that Eggtronic technologies are already fully compliant with the new regulations. Our technologies such as QuarEgg, SmartEgg, and ClassEgg achieve up to 95% efficiency and offer extremely flat efficiency curves for every output and input condition, which cuts energy losses by half or more compared to the Level VII standards.

Take, for example, a 100W adapter that operates with the 89% efficiency mandated by Level VII. That means, in normal operation, 12.4W will be lost (largely as heat). An Eggtronic solution operating at 95% efficiency, however, will lose only 5.3W, which is a saving of 7.1W and a reduction in power loss of 57%. Considering that, the Eggtronic architectures also consume less power in low and no-load situations, and with every input (from 90VAC to 230VAC), the energy saving (which is power saving integrated over time) can be even higher.

Also, Eggtronic has always made cost reduction of the converter a priority. This means that adopting Eggtronic architectures and controllers helps both to save energy and money to build smaller, more eco-friendly and cost-effective power converters.

As a result, from home appliances to lighting, consumer products to office equipment and HVAC to medical and industrial technologies, customers who choose Eggtronic technologies can have the peace of mind that their power conversion architectures are future-proofed for the latest global legislation.