In its report to Congress last year, the Environmental Protection Agency (EPA) said power consumption in data centers had more than doubled between 2000 and 2005 and will likely double again by 2011, costing upward of $7.4 billion annually unless energy-efficiency programs are implemented. According to a white paper by Neil Rasmussen, a founder and the chief technical officer of American Power Conversion (APC), West Kingston, R.I., it is possible to dramatically reduce the electrical consumption of typical data centers through appropriate design of both the network-critical physical infrastructure and the information technology (IT) architecture. Both, as a general rule, use approximately half of the total power consumed by the center.
The first ingredient of a more energy efficient data center, according to Jack Pouchet, director of energy initiatives at Emerson Network Power, St. Louis, is measurement and monitoring.
“Installing meters and submeters and measuring power consumption provides energy usage information that allows the data center to discern patterns and help determine where energy efficiency improvements can be made,” he said.
The role of the electrical contractor is examining where meters can be installed without unplanned service interruption.
“And since data centers have uninterruptible power supply [UPS] systems, the electrical contractor can also work with the supplier to understand the IT server loads of the center and suggest improvements,” Pouchet said.
Getting the data center’s size correct also helps ensure energy efficiency, said Carl Cottuli, vice president of APC’s data center science center.
“The electrical contractor can help make certain that the center is designed for the load required, ensuring that energy is not wasted,” he said.
In addition, it’s important to place the components of the cooling system as close as possible to the IT equipment, as this saves energy.
“Cooling equipment efficiency is based on the temperature of the air it is trying to cool and how far the air needs to be moved,” Cottuli said.
Finally, according to Chris Loeffler, global application manager for data center solutions at Eaton Corp., Cleveland, data center energy efficiency can entail using high efficiency products by locating the center in an area that has low-cost energy or where it can use free cooling and by examining hybrid products, Energy Star power distribution products, and National Electrical Manufacturers Association (NEMA) TP1 standard-compliant transformers.
“The design of the center can somewhat control whether, for example, the cooling system is operating efficiently with the least amount of energy possible,” he said.
One of the electrical contractor’s assets is the years of experience it has working with the basic elements of electrical design.
“The electrical contractor can use its expertise to help the design team and center owner understand the benefits and costs-savings of using the most appropriate system and to ensure that the infrastructure is not over-designed but, instead, provides the most energy efficient and safe data center,” Pouchet said.
Most of the obstacles to data center efficiency are the short-term decisions made to reduce capital expenses that sacrifice long-term operating costs, according to Cottuli. If a highly efficient UPS system, for example, is 20 percent more costly upfront but saves more than that in operating costs over time, then that system is the more efficient choice. Cottuli also cited the mistake people often make of assuming that efficiency is a single number as being a barrier to creating an energy-efficient data center.
“Efficiency is actually a curve between 0 percent and 100 percent load and requires determining the optimal range in which equipment operates,” he said.
Another barrier to data center efficiency is that the IT department and the facility management team are not usually linked, according to Pouchet.
“The most the electrical contractor can do is facilitate discussions between the two departments so that they understand each other’s needs and work together to determine the data center’s energy consumption needs and improve efficiency,” Pouchet said.
The data center owner, basing system redundancy decisions entirely on the center’s mission-critical applications, also compromises data center efficiency.
“The electrical contractor can help the owner examine which processes need to have high levels of redundancy and account for those rather than having the same backup systems available for all systems in the center,” Cottuli said.
Some equipment providers, according to APC, offer complete standardized data center design specifically engineered for efficiency, and energy-efficiency audit services are available for users desiring to reduce power consumption in existing data centers. The costs saving opportunities have been shown to be very large, yet the investment required to achieve them is small, particularly when compared with legacy approaches to data center design.
“Electrical contractors should get to know equipment manufacturers and work with them to perform electrical assessments for data centers to determine gaps in power efficiency and to examine opportunities to reduce consumption,” Pouchet said.
BREMER, a freelance writer based in Solomons, Md., contributes frequently to ELECTRICAL CONTRACTOR. She can be reached at 410.394.6966 or firstname.lastname@example.org.