Data centers are massive power consumers, and managing power usage has become an increasingly important factor in managing overall data center costs. Data center power efficiency is gauged using power usage effectiveness (PUE), a measure developed by The Green Grid. Improving PUE requires an investment in intelligent power distribution infrastructure. Most data centers run at a PUE of 2.0 — so for every dollar of energy used for the IT resources, another dollar is used on energy for operating and cooling the facility. A highly efficient data center can get its PUE score down to 1.3 or 1.4.

In our recent e-book, Basic vs. Intelligent PDUs: Understanding the Differences, 2N Systems and our partner Raritan explain how selecting the right power distribution units (PDUs) can boost power usage effectiveness in data centers.

Power usage effectiveness is a measure that compares total facility power to the amount of power actually consumed by IT equipment. The process of converting grid power and distributing it at voltage and current levels that can be consumed by data center hardware is often inefficient. Some of that power is lost as heat, which then requires cooling equipment to maintain a suitable operating environment. That cooling equipment also requires more power (as much as 37% of total data center energy in some cases), and creates additional heat losses.

Many data centers have responded by purchasing more energy efficiency hardware, but that is just one step in maximizing power usage effectiveness. Selecting the right PDU equipment can also drive improvements in efficiency.

A data center rack PDU is a device fitted with many outlets that can distribute power to servers, storage devices, and networking equipment in the data center. These PDUs fall into two categories: Basic PDUs and intelligent PDUs. Intelligent PDUs, such as the PX series from Raritan, provide advanced features such as power metering, environmental monitoring, and remote outlet control that can help improve PUE.

There are several different types of intelligent PDUs, including metered inlet or outlet PDUs, switched PDUs, and switched PDUs with outlet metering. A key feature of all of them is the ability to determine power usage and available capacity at the rack, which makes it easier to provision equipment. Switched PDUs offer the additional features of controlled on/off switching of outlets, remote power cycling, and the ability to remotely power off devices that aren’t in use.

Intelligent PDUs can also warn managers if a circuit is at risk of overloading, as well as alert them when and where a circuit trip has occurred so it can be quickly reset. Additionally, these devices help gather data about power usage that can help managers better balance and reallocate energy resources to improve power usage effectiveness.

For example, eBay has reduced operating costs at its new data centers by 50% using intelligent PDUs that provide energy consumption data for every power supply and every server.

There are other strategies that can help improve power usage effectiveness as well. In general, anything that reduces heat generation or increases cooling effectiveness will improve PUE.

For new builds, the data center itself should be designed to effectively address cooling needs, with IT assets deployed in contained spaces with dedicated hot air return plenums — so that cooling units are as efficient as possible. Locating data centers in climate-neutral or very cool geographic locations also reduces the need for artificial cooling.

In addition to improving power usage effectiveness, these strategies will ultimately save your company money by reducing overall energy consumption and waste.

To learn more about how PDU selection can address energy efficiency, download and read our e-book, Basic vs. Intelligent PDUs: Understanding the Differences, here.