- Better Buildings Challenge partners must reduce their energy use by 20 percent over the next decade.
- Strategies include hot air containment, free cooling and installing variable speed drives on fans.
- Consolidating facilities and installing ENERGY STAR® rated IT equipment are other strategies.
Because of the rapid growth in data center energy consumption, the DOE recently added data centers to the Challenge. Around 20 partners have joined and committed to reduce their energy use by at least 20 percent over the next decade.
So how do you achieve such an energy reduction? Here's how three partners did it.
Hold the hot air
Intuit achieved 21 percent energy savings in 2015 at its 231,280-square-foot Quincy, Wash. facility, which houses a capacity of more than 4 megawatts (MW). According to facilities manager Dave Breland, this was achieved by adding hot air containment and increasing the secondary chilled water temperature set point in order to increase water-side economizer operation and reduce chiller run time.
After the server's entering air temperatures were raised to match ASHRAE TC9.9 Data Center Networking Equipment Standards, the difference in cold and hot air temperature wasn't enough to prevent some of the hot air from re-entering the front of the servers. To combat this problem, they installed a hot-aisle containment system.
These strategies were implemented over three years, lowering the power usage effectiveness (PUE) from 1.52 to 1.35 and saving an estimated $130,600 in energy costs. The facility was also awarded ENERGY STAR® certification three years in a row; its current ENERGY STAR score is 97.
Take advantage of free cooling
San Francisco-based Digital Realty Trust (DRT) has committed to reducing non-IT energy use over a portfolio of 11 data centers totaling 20 MW of utility consumption. DRT improved energy performance by 17 percent from a 2013 baseline, with an ultimate goal of 20 percent by 2024. The company uses an in-house data center infrastructure management (DCIM) tool to measure and manage its properties.
DRT worked with primary customers in their Lithia Springs data center to reduce energy. The facility maximized free cooling by tuning cooling systems to take advantage of outside air using economizers. Other strategies included fine-tuning or installing variable-frequency drives (VFDs) on computer room air handlers (CRAHs) and implementing hot air containment. These improvements helped DRT earn ENERGY STAR® certification
Match that speed
eBay has committed to reducing the energy intensity of its 302,000 square feet of data centers by 60 percent over a 10 year period and reaching a 1.278 power usage effectiveness (PUE) by 2021. eBay installed high-efficiency motors (95 percent) and new VFDs for the fans on each of 83 chilled-water CRAH units at its 7,300-kW Tier IV data center in Phoenix, Ariz.
The PUE was recently improved to 1.59, a nearly 17 percent reduction. The total building electrical load decreased by 7 percent. Payback was estimated at 2.5 years from an initial cost of $750,000. eBay achieved 25 percent energy savings in 2015.
Rise to the challenge
If you want to challenge yourself even more, join the Data Center Accelerator program. Consider consolidating facilities and installing new ENERGY STAR rated IT equipment to help achieve this goal.
If all U.S. data centers were 20 percent more efficient, more than 20 billion kWh would be saved by 2020 or roughly $2 billion.