H-Connect Joomla Hosting Templateo

PAR⁴ Energy Efficiency Rating

Jointly developed by Underwriters Laboratories and Power Assure

PAR⁴ is an energy efficiency rating jointly developed by Underwriters Laboratories (UL) and Power Assure to accurately measure IT equipment power usage. Power Assure has tested hundreds of servers and found that the back plate power labels and vendor specifications are almost always overstated (even worse, in some cases the labels understate power use). Either way, it is very difficult to plan your capacity optimally without knowing how much power your servers actually consume. 

Click to watch a video overview of PAR⁴.

Find Stranded Power

Faced with increasing demand for new applications, data centers are running out of power, even when the racks or rooms are half-full. Data centers are typically provisioned based on the power consumption figures provided on the server label or by the vendor. These figures are designed to be conservative and are therefore overstated, leaving much-needed power stranded throughout the data center rather than being put to productive use.

Uncover Hidden Capacity

The PAR⁴ measurement and rating gives you the accuracy needed to uncover hidden capacity in your data center and plan new builds. By re-allocating power based on actual consumption, data center operators can often double the compute capacity of the data center and elimiate the need for expansion.

Make Better Informed Decisions for IT Refresh

When selecting a new generation of server to provision, you typically use performance indicators based on processing capacity expressed in transactions per second. However, the energy consumption can differ significantly between equipment with similar performance characteristics and capabilities. Additionally, when you have to compare performance and energy efficiencies between different generations of IT equipment it further complicates your decisions. PAR⁴ ratings allow you to make these comparisons and make more informed decisions.

Accurate Real-life Measurements

The PAR⁴ rating measures servers under real-life load conditions to certify and rate IT equipment accurately, as well as provide normalized measurements to compare efficiency across multiple generations of IT equipment.

The PAR⁴ methodology takes four measurements to obtain real-world power consumption figures: when the equipment is off, idle, loaded and at peak. With these measurements, PAR⁴ calculates the transactions per second per watt (Tps/W) at 100% CPU load.

Teamed with UL for PAR⁴ Certification

To make it easy and ubiquitous for hardware vendors to publish accurate power consumption figures, UL, the leader in compliance testing solutions, teamed with Power Assure to provide equipment manufacturers with PAR⁴ energy performance testing and certification as part of UL’s standard product certification process. With PAR⁴ included, the UL certification provides a standard for data center managers to assess their IT equipment energy efficiency for accurate capacity planning as well as for ongoing hardware refresh programs.