Efficiency is the output power divided by the input and varies with the amount of power delivered to the load. The remaining power drawn from the wall but not reaching the load is converted into heat, leading to power wastage and heating problems. At high efficiencies, there is less power wastage which translates to operational benefits.
The power supply units are most efficient at between 50 and 75 percent load, lowest at low loads and slightly less at full load.
The 80 Plus certification program has continued to evolve and currently has 6 different levels, starting from Basic to titanium. Below are the various certification levels at specified load and supply voltages. The 80 Plus titanium level is a new entry which offers the best efficiency and mostly available on high wattage units.
115V internal non-redundant
| Certification | 10% Load | 20% Load | 50% Load | 100% Load |
|---|---|---|---|---|
| 80 PLUS Basic | 80% | 80% | 80% | |
| 80 PLUS Bronze | 82% | 85% | 82% | |
| 80 PLUS Silver | 85% | 88% | 85% | |
| 80 PLUS Gold | 87% | 90% | 87% | |
| 80 PLUS Platinum | 90% | 92% | 89% | |
| 80 PLUS Titanium | 90% | 92% | 94% | 90% |
230V internal redundant
| Certification | 10% Load | 20% Load | 50% Load | 100% Load |
|---|---|---|---|---|
| 80 PLUS Basic | ||||
| 80 PLUS Bronze | 81% | 85% | 81% | |
| 80 PLUS Silver | 85% | 89% | 85% | |
| 80 PLUS Gold | 88% | 92% | 88% | |
| 80 PLUS Platinum | 90% | 94% | 91% | |
| 80 PLUS Titanium | 90% | 94% | 96% | 91% |
All these are required to have at least a 0.90 power factor and 0.95 for the platinum Titanium supplies.
Benefits of an 80 Plus certified power supply
- Energy savings on electricity
- Reduced heat dissipation means less noise from cooling fans since the will spins at lower speeds, hence reduced cooling costs and improved system reliability.
- Reduced room cooling costs
- Environmental friendly
- A high power factor value will reduce unbalanced load charges
- Enough headroom for future upgrades.
It is more practical to achieve high efficiencies in high wattage supplies. The Gold, Platinum and titanium are thus more common in high wattage power supplies as compared to the standard desktop supplies.