14 Aug Efficient Data
By Lorne Bell
Data centers power our digital lives, using immense amounts of energy to connect people and information around the world. Now, LEED is helping the world’s top data companies find new paths to energy efficiency.
If you’ve ever left a running laptop on a surface for too long, you know the kind of heat that it can generate. Now imagine that amount of heat magnified by ceiling-high server towers that fill buildings the size of football fields. Data centers are designed to run 24 hours a day, every day of the year.
Powering and cooling these information hubs requires massive amounts of energy—consider that one data center can use as much energy as a small town. Cumulatively, data centers across the U.S. used 70 billion kWh of electricity in 2014, according to Lawrence Berkeley National Lab’s Data Center Energy Usage Report. That’s about 2 percent of the nation’s electricity, the same amount used by some 6.4 million U.S. homes.
DPR’s Prineville, Oregon, data center for Facebook is one of the most energy efficient in the world, featuring an innovative cooling system created for the unique climate characteristics of central Oregon. The entire facility achieved LEED Gold certification.
To mitigate the environmental and financial costs, companies such as Apple, Facebook, and Digital Realty Trust are turning to the U.S. Green Building Council’s (USGBC) Leadership in Environmental and Energy Design (LEED) rating system. While LEED standards have been available to guide the sustainable design and construction of data centers for years, a new adaptation in LEED v4 specific to the space type is addressing the unique needs and circumstances these projects face.
The new data center guidance was crafted with input from and for the big data industry, a process that began in 2012. “We were starting to see this growing section of the market with more and more data centers out there, but our LEED certification numbers weren’t reflecting that,” says Corey Enck, vice president of LEED technical development.
So, Enck and his colleagues convened a working group of more than a dozen data industry leaders—data company owners, developers, designers, and contractors—and asked a simple question: What are the barriers in the LEED ratings system that are preventing data centers from certifying?
The group responded enthusiastically, pointing to data centers as energy intensive facilities unlike any other building covered under LEED. For one, the energy requirements of data center equipment surpass the requirements of even large commercial buildings’ equipment. Data centers also have far fewer occupants than commercial or residential buildings of similar size, so LEED credits for indoor air quality were often irrelevant. And water efficiency can be a significant factor in data centers’ sustainability profile, as cooling systems often circulate water to regulate indoor temperature.
“Data centers have so many nonstandard energy uses,” says Enck, “that LEED didn’t have the baseline for those projects to show how they’re actually saving energy.”
Out of the group’s work came two adaptations with modified benchmarks for data centers’ unique characteristics and challenges. The adaptations apply to new (LEED for Building Design and Construction) and existing (LEED for Operations and Maintenance) data centers, and focus on four key areas.
First, data centers can now more easily evaluate their energy models to earn LEED credits. The new guidelines take into account Power Usage Effectiveness (PUE), a data industry measure that tracks IT equipment energy loads as a proportion of a data center’s overall energy use. By incorporating PUE, the data centers adaptation allows owners, developers, contractors, and LEED reviewers to readily observe energy and cost savings.
Next, the commissioning credits require a commissioning agent with experience in overseeing data center design and construction. This ensures a fair commissioning process suited for data centers’ unique design elements.
USGBC also adapted LEED’s Indoor Environmental Quality (EQ) credits for data centers’ low occupancy rates. Under this category, thermal comfort credits do not apply as broadly to data centers’ spaces, and enhanced indoor air quality credits no longer require filtration of the outside air to be at the same level required for other LEED-certified buildings.
Finally, the new Cooling Tower Water Use Reduction credit addresses water in cooling towers, which are often used to moderate temperatures in data centers’ server rooms. The new benchmark acknowledges data centers’ large cooling capacity and provides LEED credits for achieving water efficiencies within these systems.
A data center must provide massive cooling power for its servers. LEED BD+C: Data Centers addresses the unique needs of these energy-intense buildings to improve efficiency.
The new adaptation is already having an impact on the market. Under LEED v2009, data centers comprised just 3 percent of LEED-certified projects. Under LEED v4, that number jumped—15 percent of projects certified under BD+C are data centers.
LEED for data centers comes at a pivotal point in the data industry, which is seeing exponential growth in global demand. According to Cisco, annual global IP traffic will reach 3.3 zettabytes by 2021. In 2016, the annual rate was just 1.2 zettabytes. Put simply, by 2021, households will consume almost three times as much online data as they did five years earlier.
At the same time, data centers are actually becoming more energy efficient by experimenting with new technologies and sustainable designs. They’re locating buildings in cooler climates, replacing central heating and cooling plants with ductless distribution systems, and improving IT hardware to allow servers to function at temperatures of 85°–90°F, rather than the typical 70°F. LEED-certified data centers are both fostering energy efficiencies and incorporating benchmarks, such as sustainably sourced construction materials, diversion of landfill waste, and stormwater recapture to provide backup water supplies.
The results? While data center energy consumption grew 90 percent from 2000 to 2005, it only grew 24 percent from 2005 to 2010. Despite a boom in new data center construction, data center energy use grew by only 4 percent from 2010 to 2014. And LEED-certified data centers are reducing their overall environmental impact in the communities where they’re built.
For Apple, LEED-certified data centers are part of the company’s commitment to powering corporate buildings and retail stores with 100 percent renewable energy. In 2010, only 16 percent of Apple’s buildings were fueled by renewable energy. That number is now at 96 percent, and all of Apple’s data centers run entirely on renewables.
That includes a fleet of LEED Platinum data centers in Oregon, Nevada, and North Carolina. At Apple’s Prineville, Oregon, facility, wind and micro-hydro projects generate 99 percent of the data center’s energy load. In North Carolina, Apple’s LEED Platinum data center generates 60 to 100 percent of its daily energy use from solar arrays and biogas fuel cells. To cool its servers, the facility uses outside air and a waterside economizer at night and during cool-weather hours, which allows the chillers to be turned off 75 percent of the time.
Facebook is also taking advantage of the energy-efficient and sustainable strategies of LEED. The social media company opened its first LEED Gold data center in 2011, and the project (also located in Prineville) used 27 percent recycled material for the building’s construction. The 300,000-sq-ft facility also recycled 83 percent of its construction waste, diverting 530 tons of waste from landfills.
Apple’s Prineville, Oregon, Data Center’s wind micro-hydro projects generate 99 percent of the data center’s energy load.
The center itself includes energy-efficient servers, and the heat generated by its servers is used to heat the data center’s office space. The building features a low-energy evaporative cooling system, which uses central Oregon’s high desert setting and low humidity to eliminate traditional air conditioners.
Overall, the Facebook Prineville center uses 70 percent less water for cooling purposes than an average data center and 28 percent less energy.
Facebook has since opened several other LEED-certified data centers, including the company’s first European data center in Lulea, Sweden, in 2013. The 300,000-sq-ft LEED Gold facility uses hydro power and taps the region’s frigid climate to cool its servers. That means big savings, according to California-based DPR Construction, which has built several Facebook data centers and collaborated on the Lulea facility.
Christopher Gorthy, project executive at DPR, says even incremental improvements in data centers’ massive power loads can make a significant impact.
“If you have a 100,000-square-foot data center, it may draw millions of dollars in power in a year,” says Gorthy. “If you save 1 percent of that power, you’ll literally save hundreds of thousands of dollars per year. So, it’s not just the right thing to do from an energy standpoint, but also for the bottom line.”
Since 2006, DPR has built $4.8 billion in data center projects, representing nearly 20 percent of the company’s overall revenue. “Companies want them built faster and faster,” says Gorthy, “so we’re building them at lightning speed. We just completed a 650,000-square-foot data center shell in less than seven months.”
One of DPR Construction’s clients is San Francisco’s Digital Realty Trust (DRT), which develops and manages 145 co-location data centers across 33 global cities. Colocation centers house more than one data company, so DRT uses LEED Core and Shell, which is designed for projects for which the owner or administrator has control of the design and construction of mechanical elements but not the tenant fit-out. In this way, DRT ensures basic energy efficiencies and sustainability benchmarks for construction materials, landfill diversion, and water use, and has set a goal of building only LEED Silver data centers.
Along with its LEED certifications, the company recently procured 400,000 annual megawatt-hours of energy generated from a wind farm in Texas, and it now uses a pumped refrigerant cooling system that requires no water to cool its data centers’ server rooms. The system allows DRT to drastically reduce its data centers’ water use and earn Advanced Refrigerant Management credits toward LEED certification. More than 600 of the systems have been deployed across DRT’s portfolio, including data centers in drought-ravaged California, saving 350 million gallons of water each year.
For Aaron Binkley, director of sustainability at DRT, sustainable design and construction are helping data centers keep pace in an industry that seems to have no top speed.
“Our starting point is to build a building that treads lightly on the environment and holds us accountable to a high standard, and LEED provides a consistent standard,” says Binkley.