80 PLUS
Encyclopedia
80 PLUS is an initiative to promote energy efficiency
in computer power supply units (PSU). It certifies products that have more than 80% energy efficiency at 20%, 50% and 100% of rated load, and a power factor
of 0.9 or greater at 100% load.
That is, PSUs will waste 20% or less electric energy as heat at the specified load levels, thus reducing electricity use and bills compared to less efficient PSUs. Sometimes rebate
s are given for manufacturers who use 80 PLUS-certified PSUs.
Redundant are typically used in data center
s.
For the higher certification levels, the requirement of 0.9 or better power factor was extended to apply to 20% and 50% load levels, as well as at 100% load. The Platinum level requires 0.95 or better power factor for servers.
The Climate Savers Computing Initiative
efficiency level targets for workstations for 2007 through 2011, correspond to the 80 PLUS certification levels. From July 2007 through June 2008, basic 80 PLUS level (Energy Star 4.0). For next year target is, 80 PLUS bronze level, the following year 80 PLUS silver, then 80 PLUS gold, and finally platinum.
Although some power supply manufacturers name their products with similar names, like "85 Plus," there is no such official certification or standard.
For a given power supply, efficiency varies depending on how much power is being delivered. Supplies are typically most efficient at between half and three quarters load, much less efficient at low load, and somewhat less efficient at maximum load. Older ATX power supplies were typically 60% to 75% efficient. To qualify for 80 PLUS, a power supply must achieve at least 80% efficiency at three specified loads (20%, 50% and 100% of maximum rated power). However, 80 PLUS supplies may still be less than 80% efficient at lower loads. For instance, an 80 PLUS, 520 watt supply could still be 70% or less efficient at 60 watts (a typical idle power for a desktop computer). Thus it is still important to select a supply with capacity appropriate to the device being powered.
It is easier to achieve the higher efficiency levels for higher wattage supplies, so gold and platinum supplies may be less available in consumer level supplies of reasonable capacity for typical desktop machines.
Typical computer power supplies may have power factor
s as low as 0.5 to 0.6. The higher power factor reduces the peak current draw, reducing load on the circuit or on an uninterruptible power supply
.
Reducing the heat output of the computer helps reduce noise
, since fans do not have to spin as fast to cool the computer. Reduced heat and resulting lower cooling demands may increase computer reliability.
The testing conditions may give an unrealistic expectation of efficiency for heavily loaded, high power (rated much larger than 300 W) supplies. A heavily loaded power supply and the computer it is powering generate significant amounts of heat, which may raise the power supply temperature, which is likely to decrease its efficiency. Since power supplies are certified at room temperature, this effect is not taken into account.
80 PLUS does not set efficiency targets for very low load. For instance, generation of standby power
may still be relatively inefficient, and may not meet requirements of the One Watt Initiative
. Testing of 80 PLUS power supplies shows that they vary considerably in standby efficiency. Some consume half a watt or less in standby with no load, where others consume several times as much at standby, even though they may meet higher 80 PLUS certification requirement levels. Inefficiencies in generating standby power are magnified by the amount of time that computers spend turned off.
Efficient energy use
Efficient energy use, sometimes simply called energy efficiency, is the goal of efforts to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature...
in computer power supply units (PSU). It certifies products that have more than 80% energy efficiency at 20%, 50% and 100% of rated load, and a power factor
Power factor
The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load over the apparent power in the circuit, and is a dimensionless number between 0 and 1 . Real power is the capacity of the circuit for performing work in a particular time...
of 0.9 or greater at 100% load.
That is, PSUs will waste 20% or less electric energy as heat at the specified load levels, thus reducing electricity use and bills compared to less efficient PSUs. Sometimes rebate
Rebate (marketing)
A rebate is an amount paid by way of reduction, return, or refund on what has already been paid or contributed. It is a type of sales promotion marketers use primarily as incentives or supplements to product sales. The mail-in rebate is the most common...
s are given for manufacturers who use 80 PLUS-certified PSUs.
History
- Ecos & EPRI develop the Generalized Internal Power Supply Efficiency Test Protocol for desktop derived multi-output power supplies
- In March 2004 the 80 PLUS idea was presented as an initiative at the ACEEE Market Transformation Symposium.
- In February 2005 the first market ready power supply was created by Seasonic.
- In 2006 Energy StarEnergy StarEnergy Star is an international standard for energy efficient consumer products originated in the United States of America. It was first created as a United States government program during the early 1990s, but Australia, Canada, Japan, New Zealand, Taiwan and the European Union have also adopted...
added 80 PLUS requirements to their upcoming (in effect since July 2007) Energy Star 4.0 computer specifications. - In November and February 2006 HP and Dell certify their PSUs to the 80 PLUS specification.
- July 20, 2007 — ENERGY STAR Computer Specification 4.0 goes into effect. The specification includes 80 PLUS power supply efficiency levels for desktop computers.
- December 2007 — over 200 PSUs on the market are 80 PLUS certified and it is becoming the market standard.
- First quarter 2008 — Standards revised to add Bronze, Silver and Gold higher efficiency level certifications.
- October 2009 - Added specification for Platinum efficiency level.
Efficiency level certifications
| 80 PLUS Test Type | 115V Internal Non-Redundant | 230V Internal Redundant | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Fraction of Rated Load | 10% | 20% | 50% | 100% | 10% | 20% | 50% | 100% | |
| 80 PLUS | 80% | 80% | 80% | ||||||
| 80 PLUS Bronze | 82% | 85% | 82% | 81% | 85% | 81% | |||
| 80 PLUS Silver | 85% | 88% | 85% | 85% | 89% | 85% | |||
| 80 PLUS Gold | 87% | 90% | 87% | 88% | 92% | 88% | |||
| 80 PLUS Platinum | 90% | 92% | 89% | 90% | 94% | 91% | |||
| 80 PLUS Titanium | 90% | 94% | 96% | 91% | |||||
Redundant are typically used in data center
Data center
A data center is a facility used to house computer systems and associated components, such as telecommunications and storage systems...
s.
For the higher certification levels, the requirement of 0.9 or better power factor was extended to apply to 20% and 50% load levels, as well as at 100% load. The Platinum level requires 0.95 or better power factor for servers.
The Climate Savers Computing Initiative
Climate Savers Computing Initiative
The Climate Savers Computing Initiative is a nonprofit group of consumers, businesses and conservation organizations dedicated to promoting smart technologies that can improve the power efficiency and reduce the energy consumption of computers...
efficiency level targets for workstations for 2007 through 2011, correspond to the 80 PLUS certification levels. From July 2007 through June 2008, basic 80 PLUS level (Energy Star 4.0). For next year target is, 80 PLUS bronze level, the following year 80 PLUS silver, then 80 PLUS gold, and finally platinum.
Misleading power supply advertising
There have been a few instances where companies claim or imply that their supplies are 80 PLUS when they have not been certified, and in some cases do not meet the requirements. When a company resells an OEM power supply under a new name it must be certified under the new name and company, even if the OEM supply is certified. In some instances a reseller has claimed a higher wattage than the supply can deliver - in which case the reseller's supply would not meet 80 PLUS requirements. The 80 PLUS web site has a list of all certified supplies, so it is possible to confirm that a supply really meets the requirements.Although some power supply manufacturers name their products with similar names, like "85 Plus," there is no such official certification or standard.
What it means
The efficiency of a computer power supply is its output power divided by its input power. The remaining power is converted into heat. For instance, a 600-watt power supply with 60% efficiency running at full load would draw 1000 W from the mains and would therefore waste 400 W as heat. On the other hand a 600-watt power supply with 80% efficiency running at full load would draw 750 W from the mains and would therefore waste only 150 W as heat.For a given power supply, efficiency varies depending on how much power is being delivered. Supplies are typically most efficient at between half and three quarters load, much less efficient at low load, and somewhat less efficient at maximum load. Older ATX power supplies were typically 60% to 75% efficient. To qualify for 80 PLUS, a power supply must achieve at least 80% efficiency at three specified loads (20%, 50% and 100% of maximum rated power). However, 80 PLUS supplies may still be less than 80% efficient at lower loads. For instance, an 80 PLUS, 520 watt supply could still be 70% or less efficient at 60 watts (a typical idle power for a desktop computer). Thus it is still important to select a supply with capacity appropriate to the device being powered.
It is easier to achieve the higher efficiency levels for higher wattage supplies, so gold and platinum supplies may be less available in consumer level supplies of reasonable capacity for typical desktop machines.
Typical computer power supplies may have power factor
Power factor
The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load over the apparent power in the circuit, and is a dimensionless number between 0 and 1 . Real power is the capacity of the circuit for performing work in a particular time...
s as low as 0.5 to 0.6. The higher power factor reduces the peak current draw, reducing load on the circuit or on an uninterruptible power supply
Uninterruptible power supply
An uninterruptible power supply, also uninterruptible power source, UPS or battery/flywheel backup, is an electrical apparatus that provides emergency power to a load when the input power source, typically mains power, fails...
.
Reducing the heat output of the computer helps reduce noise
Quiet PC
A quiet PC is a personal computer that makes little noise. Common uses for quiet PCs include video editing, sound mixing, home servers, and home theater PCs. A typical quiet PC uses quiet cooling and storage devices and energy-efficient parts....
, since fans do not have to spin as fast to cool the computer. Reduced heat and resulting lower cooling demands may increase computer reliability.
The testing conditions may give an unrealistic expectation of efficiency for heavily loaded, high power (rated much larger than 300 W) supplies. A heavily loaded power supply and the computer it is powering generate significant amounts of heat, which may raise the power supply temperature, which is likely to decrease its efficiency. Since power supplies are certified at room temperature, this effect is not taken into account.
80 PLUS does not set efficiency targets for very low load. For instance, generation of standby power
Standby power
Standby power, also called vampire power, vampire draw, phantom load, or leaking electricity , refers to the electric power consumed by electronic and electrical appliances while they are switched off Standby power, also called vampire power, vampire draw, phantom load, or leaking electricity...
may still be relatively inefficient, and may not meet requirements of the One Watt Initiative
One Watt Initiative
The One Watt Initiative is an energy-saving initiative by the International Energy Agency to reduce standby power-use by any appliance to not more than one watt in 2010, and 0.5 watts in 2013, which has given rise to regulations in many countries and regions.-Standby power:Standby power,...
. Testing of 80 PLUS power supplies shows that they vary considerably in standby efficiency. Some consume half a watt or less in standby with no load, where others consume several times as much at standby, even though they may meet higher 80 PLUS certification requirement levels. Inefficiencies in generating standby power are magnified by the amount of time that computers spend turned off.
See also
- Climate Savers Computing InitiativeClimate Savers Computing InitiativeThe Climate Savers Computing Initiative is a nonprofit group of consumers, businesses and conservation organizations dedicated to promoting smart technologies that can improve the power efficiency and reduce the energy consumption of computers...
- Computer power supply
- Green computingGreen computingGreen computing or green IT, refers to environmentally sustainable computing or IT. In the article Harnessing Green IT: Principles and Practices, San Murugesan defines the field of green computing as "the study and practice of designing, manufacturing, using, and disposing of computers, servers,...
- IT energy managementIT energy managementIT energy management is the analysis and management of energy demand within the information technology arena. IT energy demand accounts for approximately 2% of global CO2 emissions, approximately the same level as aviation...
- Power managementPower managementPower management is a feature of some electrical appliances, especially copiers, computers and computer peripherals such as monitors and printers, that turns off the power or switches the system to a low-power state when inactive. In computing this is known as PC power management and is built...
- Performance per wattPerformance per wattIn computing, performance per watt is a measure of the energy efficiency of a particular computer architecture or computer hardware. Literally, it measures the rate of computation that can be delivered by a computer for every watt of power consumed....
- Quiet PCQuiet PCA quiet PC is a personal computer that makes little noise. Common uses for quiet PCs include video editing, sound mixing, home servers, and home theater PCs. A typical quiet PC uses quiet cooling and storage devices and energy-efficient parts....