Early last year, Emerson executives made the strategic decision that the company needed a new data center. Upon coming to this conclusion they also understood that this new facility would present a significant opportunity for the company to showcase the energy-efficient technologies from Emerson Network Power, as well as implement many of the efficiency strategies the company has been advancing within the industry during the last few years.

One of the visions for the new data center is to show how incorporating these technologies and strategies into a data center can directly lead to better performance and reduced energy consumption, while also supporting LEED Certification initiatives. It could also become a model for being energy efficient in a financially conscious manner.

The cutaway illustrates the mechanical systems in the new facility, plus solar panels on the roof.

State-Of-The-Art Data Center

Emerson, a diversified global manufacturing and technology company with more than 260 manufacturing locations worldwide, currently maintains about 100 data centers and network closets across the global. These computing environments range in size from small network closets, 100-200 square feet (sq ft) to large data centers that span thousands of square feet. Many of the data centers were colocation sites, and some of the other sites maintained by the company contained aged equipment–some as old as 20 years old.

In an effort to realize energy-efficiency gains and reduce operating costs, the decision was made to consolidate as many as possible of the computing environments into four main facilities globally, two of which would be located in North America.

Also, by utilizing the Emerson Network Power technology developed to support state-of-the-art, mission-critical data centers, Emerson could further reduce energy consumption, enhance operational performance, and create a premier technology showcase featuring the latest energy-efficient technologies and best practices.

The first piece in this initiative is the new corporate data center currently being constructed at the company’s St. Louis, MO, campus. The 35,000-sq ft data center is slated to open in summer 2009 and will support the $24 billion company’s global network.

The innovative facility will feature numerous Emerson Network Power products from brands such as Aperture, ASCO, Knurr, and Liebert interacting with technologies from the world’s leading IT companies. Collectively, these technologies comprise a highly available, reliable, and concurrently maintainable physical infrastructure that can be remotely managed.

The data center will have three layers of redundancy, with dual-utility feeds, redundant UPS protection, and on-site generators. Additionally, the data center will be scalable, with redundant dual-bus power capacity starting at 1,350 kilowatts (kW) and ultimate UPS systems scalability up to 4,050 kW across dual paths. Cooling capacity will be upwards of 300 watts per square foot.

The building's floor plan shows that it is primarily dedicated to data center operations, with room for future growth.

LEED Certification

Based on the data center architecture and technology infrastructure of the facility, Emerson anticipates receiving LEED Silver Certification from the U.S. Green Building Council.

Emerson is one of the first companies to voluntarily participate in the process of earning data center-based green credits in the core areas of energy efficiency, indoor environmental quality, materials, resources selection, sustainable site development, and water savings.

Fox Architects, the project’s lead architect, estimates that the design will provide Emerson an estimated energy savings of 31 percent as compared to a traditional data center. The energy-saving attributes include:
  • On-site renewable energy. The facility features one of the largest rooftop solar arrays used by a data center, which will provide 100 kW to the IT load directly through the main switchboard. Emerson will receive 13.6 percent of its day one electrical needs from the solar array.

  • Reduced building footprint. By placing the condensers on the roof, Emerson was able to reduce the project’s footprint by more than 15,000 square feet. The space saved was kept as green space.

  • Minimized heat island effect. The roof of the facility is a white TPO (ThermoPlastic Olefin) roof rated for extreme wind uplift. For this type of roof, the cost of moving from standard black to white was negligible. Energy savings for this type of roof range in the $25 per 1,000 square foot per year, or approximately $800 per year.

  • Reduced light pollution. Fox Architects designed the exterior lighting to shield all luminaires and keep excess light from spilling beyond the site boundaries or up into the atmosphere. This effectively puts the light where it’s needed and nowhere else. Interior lighting was also designed to turn off when not in use, to minimize spill lighting from interior to exterior.
As IT equipment is installed, Emerson will also follow applicable strategies recommended in Emerson Network Power’s Energy Logic approach to reducing data center energy consumption, to yield additional energy savings and achieve the LEED optimized energy performance credit – the most important part of LEED compliance.

A Cascade of Savings

Last year Emerson Network Power introduced Energy Logic, a step-by-step roadmap that provides data center and IT managers with a prioritized approach to reducing energy consumption. The approach features ten energy-saving strategies. (See figure 1)

Based on research and modeling, Energy Logic helps IT and facility managers make decisions about optimizing energy use and minimizing critical resource constraints–power, cooling and space–without compromising availability or flexibility. Energy Logic centers on “the cascade effect” which promises an average total savings of 2.84 watts for every watt saved at the processor level. (See figure 2). Energy Logic’s sequence can potentially save more than half of a data center’s load. When the energy-saving strategies of Energy Logic are applied, in the order in which they have the greatest impact, to a data center, the can potentially make available approximately two-thirds of floor space, one-third of UPS capacity, and 40 percent of precision cooling capacity.

During the design phase of the data center, Emerson worked closely with Fox Architects to identify the Energy Logic strategies that, if implemented, would help gain LEED Certification. Following are a few of those strategies.

By placing condensers on the roof, Emerson reduced the building's footprint, using the saved space to add greenspace to the campus.

1.  Blade servers. While the move to blade servers is typically not driven by energy considerations, they can play a role in energy consumption. Blade servers consume about 10 percent less power than equivalent rack-mount servers because multiple servers share common power supplies, cooling fans, and other components. More importantly, blades facilitate the move to a high-density data center architecture, which can significantly reduce energy consumption. In the new data center, Emerson will deploy blade servers as a part of the overall energy savings strategy.

2. Power distribution architecture. The critical power system represented another opportunity to reduce energy consumption. In most data centers, the UPS provides power at 480 volts, which is then stepped down via a transformer and distributed at 208/120 volts by the power distribution system.  Emerson plans to increase the operating efficiency of the IT load power supplies by increasing distribution voltage from 208 to 240 V directly to the server. This higher voltage will enable an increase in server power supply efficiency. Dell estimates that power supplies deployed in Emerson’s applications are 0.6 percent more efficient at 240 V than at 208 V. Emerson estimates that this switch to 240 V will save about 20,000 kW-hr annually.

Figure 1. Savings from various data center efficiency measures.

3. High-density supplemental cooling. Traditional room-cooling systems have proven very effective at maintaining a safe, controlled environment for IT equipment. However, optimizing data-center energy efficiency requires moving from traditional data center densities (2 to 3 kW per rack) to an environment that can support much higher densities (in excess of 30 kW). To accomplish this, Emerson will utilize the Liebert XD system to implement a cooling approach that shifts some of the cooling load from traditional precision air conditioning units to supplemental cooling units. These units pull hot air directly from the hot aisle and deliver cold air to the cold aisle. They improve data center efficiency by bringing cooling closer to the source of heat, reducing the fan power required to move air. Emerson estimates that by implementing supplemental cooling in its data center, it can reduce fan power by up to 65 percent.

4.  Variable capacity cooling. Data center systems are sized to handle peak loads, which rarely exist. Consequently, operating efficiency at full load is often not a good indication of actual operating efficiency. Newer technologies, such as digital scroll compressors and variable frequency drives in precision air conditioning units, allow high efficiencies to be maintained at partial loads. Emerson will install Liebert DS cooling units with variable capacity that track the varying load and work at the optimal power level for the room’s need. It matches cooling capacity with IT load and eliminates over cooling and improves cooling efficiency with reduced cycling. Emerson estimates that utilizing variable capacity cooling in its data center will save more than 210,000 kW-hr annually.

Emerson's new facility will also include a small conference room, among other amenities. LEED standards were referencedin all such spaces throughout the building.

5.  Monitoring and Optimization. One of the effects of rising equipment densities has been increased diversity within the data center. Rack densities are rarely uniform across a facility, and this can create cooling inefficiencies if monitoring and optimization are not implemented. Room cooling units on one side of a facility may be humidifying the environment based on local conditions while units on the opposite side of the facility are dehumidifying.

To prevent this from happening, Emerson will utilize the Liebert iCOM control system, which enables multiple cooling units to operate as a system to precisely control temperature and humidity across a room and optimize efficiency of the entire cooling system. Emerson will use the Liebert SiteScan monitoring system to provide enterprise-wide monitoring and control of virtually any piece of critical equipment. The company is also working with Aperture to help plan the data center space and power needs.

Figure 2. The Energy Logic identifies a multiplier effect in making small efficiency improvements close to the load.

Once completed, the new Emerson data center is expected to showcase how the implementation of the strategies and technologies Emerson Network Power recommends can deliver best-in-class data center performance. It will show how following applicable strategies recommended in Emerson’s Energy Logic approach will help organizations reduce data center energy consumption and gain LEED Certification. This is especially important as the industry is beginning to recognize that energy efficiency of the facility is the most important part of LEED Certification.