A Hidden Savings Opportunity
When people think about data centers, most probably picture Costco-sized facilities run by leading high-tech brands like Apple, Microsoft, Google, or Facebook. However, half of all data center energy use, or roughly one percent of all the energy generated in the USA, is used by smaller, more ubiquitous, and certainly less well-known “embedded data centers” (EDCs). Generally speaking, EDCs are data center spaces with less than 50kW of IT load. They include server rooms, server closets, localized data centers and some mid-tier data centers as well. (Data center types are defined in Table 1 below.)
EDCS are everywhere
If you work in an office, a school, or even a hospital, you most likely have an EDC in your building. Roughly 2.7 million “organization-run” EDCs are located in the United States.1 In an examination of 250 commercial buildings, the Northwest Power Conservation Council found 280 EDCs. A PG&E survey found that half of small and medium businesses housed an EDC. 2
EDCS quietly consume a lot of energy
Your EDC may be drawing 10 to 20 kilowatts of electricity all day and all night, a number that probably represents a substantial portion of the building’s total energy use. A study by ESource found that server rooms and closets can account for 23 percent of a typical office building’s energy costs, and 40% of energy use in new, high efficiency buildings.3
Why EDCs are often overlooked
For a variety of reasons, operators of EDCs don’t think about energy efficiency as much they should.
- Hidden costs. Most large data centers are metered separately from other facilities. As a result, the cost of powering a large data center is fairly easy to ascertain. EDCs, on the other hand, are rarely metered separately from other spaces within the building. As a result, it’s not always obvious how much energy EDCs use.
- Split incentives. EDC managers typically don’t shoulder the energy costs of their facility. Electricity bills are usually the responsibility of an energy or facility manager, who may not even work in the same building.
- Risk aversion. All data center managers are focused primarily on uptime and performance, and may, as a result, perceive proposed changes that are not directly tied to uptime as unnecessary risks.
- Lack of resources. EDC managers often lack the time, staff, or budget to investigate efficiency measures.
You can make data centers more efficient, even if you don’t work in IT
ENERGY STAR offers a number of resources to help facility managers, energy managers, and sustainability managers understand and address data center efficiency opportunities, including:
- 5 Simple Ways to Avoid Energy Waste in Your Data Center checklist
- Simple, plain-English explanations of 16 additional energy efficiency measures
- Educational webinars for non-technical audiences.
- Personalized technical assistance (ES provides free phone and email consultations to help you and your IT colleagues identify and take advantage of energy efficiency opportunities)
Table 1: Data Center Space Types
|Data Center Space Type||Description of Organization-Run Data Centers (No colocation or Hyper-scale cloud DCs)||Square Footage||Installed U.S. Data Centers||Average Physical Servers per Location||Embedded Data Center?|
|High-End||The primary server location for an organization. It has advanced cooling systems and redundant power; and is protected by multiple levels of physical and digital security.||>20,000||7,368||500–1,000+||No|
|Mid-tier||The primary server location for an organization. It has superior cooling systems that are probably redundant; and is usually protected by two levels of physical and digital security.||2,000–19,999||9,694||100–500||Sometimes|
|Localized||May be a primary or secondary location requiring badge or pin access, and has some power and cooling redundancy to ensure constant temperature and humidity settings||500–1,999||66,014||25-100||Yes|
|Server Rooms||A secondary computer location that usually is under IT control and may have some power and cooling as well as security capabilities.||100–999||1,265,096||5-25||Yes|
|Server Closets||A very small room or closet often outside of central IT control (often at a remote location) that has little to no security or cooling.||<100||1,377,714||<5||Yes|
|Source: Villars, Richard. IDC Market Analysis. U.S. Datacenter Census and Construction 2013 -1017 Forecast. Filing Information: October 2013, IDC #243614, Volume: 1, Tab: Markets Datacenter Trends and Strategies: Market Analysis. Table 1.|
Additional Resources for EDCs
- DOE’s Improving Energy Efficiency for Server Rooms and Closets (PDF, 673 KB) lists 14 efficiency improvements for EDCs
- Google’s Green Data Centers: Network POP Case Study (PDF, 4 KB) documents specific energy efficiency measures taken in a server room. Measures that are examined include optimized air vent tiles, temperature and humidity adjustments, cold aisle containment, and CRAC air return extensions. The initiative had a return on investment of less than one year.
- Arc Productions (PDF, 2.6 MB) shows how server power control software reduced the energy costs of a 700 square foot server room by 56%.
1 Does not include colocation or service provider data centers.
2 Source: “Small Data Center Market Study”, PG&E, December 27, 2013. Available online: http://www.calmac.org/Publications/FINAL_REPORT_PGE_Small_Data_Center_Study.pdf (PDF, 868 KB)
3 Source: 2013 E Source Energy Manager’s Roundtable: presentation entitled “Who Needs Skeletons? We’ve Got Servers in the Closets” by Mark Monroe, Chief Technology Officer and VP at DLB Associates.