Tips for Data Center Energy Efficiency

Brian Wood Blog

Energy is constantly on everyone’s mind. Homeowners, smaller businesses, and now even large-scale data centers are monitoring energy usage like never before while looking for ways to improve efficiency. Ultimately, decreased energy usage is good for everyone: more energy becomes available, it’s better for the environment in the long run, and it helps keep energy bills low.

Data Center EfficiencySource:

So how are data centers doing it? There are quite a few ways that data centers can improve their energy efficiency and Clemens Pfeiffer, CTO of Power Assure, Inc., shared some of those ideas with IT Business Edge. Here are some of the most popular as well as the most important ways that data centers are reducing energy consumption while improving efficiency:

Determining Actual Power Consumption

  • Older equipment typically uses power inefficiently and newer servers with a high idle/peak swing (above 50%) can overload circuits more frequently when incorrectly allocated and aggregated. Using the PAR4 methodology specified in the Underwriters Laboratories UL2640 standard to determine actual power consumption makes it possible to maximize server capacity while eliminating the risk of overloading circuits under peak utilization (

Reducing Cooling Power Consumption

  • In a typical data center, only about half of the available power is actually used by the IT equipment, while the vast majority goes toward cooling. Much of that power can be reclaimed by upgrading cooling systems which allow for variable cooling or make use of outside air.

Calibrating And Monitoring Cold Aisle Temperatures

  • The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) recommends adopting a hot/cold aisle configuration while increasing the cold aisle inlet temperatures to 80.6 degrees. Constantly monitoring and calibrating the temperature maximizes cooling efficiency and minimizes problems.

Matching Server Capacity To Load In Real Time

  • Even the most recently refreshed server configurations waste power during periods of low application demand. Total server power consumption can be reduced by up to 50% by matching online capacity to actual load in real-time. Runbooks can be used to automate the steps involved in power-capping and/or de/reactivating servers, whether on a predetermined schedule or in response to unanticipated events (

Eliminating The Transfer Switch

  • An AC or DC distribution bus is far more efficient during power outages than an automatic transfer switch between the grid and the generator. The bus configuration integrates all sources of power, including any on-site fuel cells and solar or wind energy, while enabling generator maintenance cycles to be used effectively.

Consolidating And Virtualizing

  • Poor server utilization is one of the biggest sources of waste in modern data centers. Virtualizing the servers can increase overall utilization from around a typical 10% to between 20% and 30% and even over 50% with more dynamic management systems. By creating several virtual servers on one device, data centers can dramatically reduce the required number of physical servers ( Successful consolidation and virtualization initiatives can also reclaim a considerable amount of rack space as well as stranded power.

Following The Moon

  • Very few organizations take full advantage of the powerful configuration of operating redundant data centers that are needed to satisfy business continuity. Having multiple and strategically-located data centers enables loads to be shifted to where power is the most stable and least expensive. Power/energy is most abundant and least expensive at night and following a “moon” strategy like this can result in considerable savings.