On July 14th, NetApp's Research Triangle Park (RTP) Data Center was the first site to be awarded Energy Star certification under this newly minted program.
They were one of the original 120 participating data centers that voluntarily participated in the program over the last 18 months and submitted and certified their data center's energy usage and efficiency information for 12 months. Those data centers formed the basis of the database that the Environmental Protection Agency (EPA) used to create the first iteration of the standard by which the applicants will be judged. In order to qualify, the site must score 75 (out of 100) or higher. The RTP data center achieved a near perfect mark by scoring a 99.
The EPA's Energy Star for data center program requirements became official last month on June 7th, after 12 months of data gathering and approximately six additional months to review and analyze the information and finalize the program. While some other sites have also submitted their formal application, NetApp was the first to submit all the required documentation and be certified by the EPA.
'Improving the energy efficiency of our nation's buildings is critical to protecting our environment,' said Jean Lupinacci, chief of the ENERGY STAR Commercial and Industrial Branch. 'NetApp is leading the way by earning EPA's ENERGY STAR for its data center.'
According to a NetApp press release, to earn the ENERGY STAR, they implemented the following features in the RTP data center:
74�F average supply air temperature: Using a higher temperature threshold on supply air (74�F instead of 55� to 60�F) allows NetApp to dramatically reduce cooling costs.
Airside economizer: The data center is cooled by using just outside air (free cooling) 67% of the time during the year.
Pressure-controlled room: Modulating fans, based on NetApp's proprietary technology, supply pressure-controlled rooms and regulate the volume of air to avoid oversupplying air and wasting energy.
Overhead air distribution: Instead of pumping cold air up through the floors (raised floors), overhead air distribution takes advantage of cold/hot air buoyancy and eliminates ductwork, reducing the energy needed for fans.
So much for the press release generalities, now here is where it gets interesting..
In an interview with Mark Skiff, Senior Director East Coast Tech Sites for NetApp, he described their quest, which started in 2006 (long before the EPA's Data Center program began) to build a high-efficiency data center for their Global Dynamic Laboratory (GDL). The GDL data center construction started in 2007 (as the Green Grid was just getting started) and it was finally completed and became operational in March 2009. The general design goals were 25 MW and 32,500 Sq ft of usable rack space, housing up to 2100 racks, with a targeted average density of 12 KW per rack.
The total project was built in a 100,000 SF, two-story 'general purpose' building to save costs. Moreover, Netapp used commercial air handlers instead of precision cooling, breaking another long-standing 'golden rule' of data center design, to save additional costs. They located the air handlers on the second floor above the data center. There is no raised floor; they ducted down the cold air (or not so cold air, since it is 75�F during business hours and is allowed to rise to 80�F when the space in unoccupied) into a cold aisle containment system and exhaust up the hot return air (which is hot). They use 55�F chilled water instead of the usual 45�F water to increase chiller efficiency (when the chillers are needed, which is only about 33 percent of the time).
Because they are in North Carolina (which can be quite humid), I asked Mark if they had any dehumidification issues since they utilized air side economizers most of the time. He indicated that they do allow the humidity to go to 75 percent RH before they disable the outside air.
While 75 percent RH is above ASHRAE's recommendations, it is within most of the leading servers' environmental specifications, but not most tape drives. When I asked if, because of the higher humidity levels, they isolated the tape backup systems and media in a more regulated environment, he politely reminded me that NetApp makes storage and tape-less disk-based backup systems and therefore they do not use any tape (side note, if you run tape drives, think twice about this).
The result -- they have achieved an annualized PUE of 1.35 (not just a snapshot at 2 a.m. on a cold night) and as noted earlier, this put them in the 99th percentile of the EPA Energy Star database.
So we say well done to Mark Skiff, who had the vision and foresight to design this project in 2006, and hats off to NetApp's management to support this project, way before the phrases Green IT and data center were commonly used in the same sentence.
As for those other sites that did not make the EPA efficiency cut, try harder. It can be done, even in a moderate climate, as NetApp demonstarted. Even if you don't want to push the environmental envelope as far as NetApp, it is time to re-evaluate the traditional designs and think outside the box.