Data center design: Energy efficiency

In the information age, data centers are one of the most critical components of a facility. If the data center isn’t reliable, business can’t be done. Energy efficiency and sustainability are key components.

By Consulting-Specifying Engineer January 27, 2014



  • Kevin V. Dickens, PE, LEED BD+C, Mission critical design principal, Jacobs Engineering, St. Louis
  • Terrence J. Gillick, President, Primary Integration Solutions Inc., Charlotte, N.C.
  • Bill Kosik, PE, CEM, BEMP, LEED AP BD+C , Principal data center energy technologist, HP Technology Services, Chicago
  • Keith Lane, PE, RCDD, NTS, RTPM, LC, LEED AP BD+C, President/CEO, Lane Coburn & Associates LLC, Bothell, Wash.
  • David E. Wesemann, PE, LEED AP, ATD, President, Spectrum Engineers Inc., Salt Lake City

CSE: According to a recent poll conducted by Consulting-Specifying Engineer, the energy efficiency and sustainability requirements within a data center were the most complex issue. Do you agree? Why or why not?

Gillick: I agree. The operating costs of data centers are significant, so even the smallest gain in energy efficiency—even a 1% or 2% reduction in annual utility costs—yields significant savings. All the low-hanging fruit has been picked, and it’s becoming increasingly difficult and more costly to achieve those incremental reductions. Owners are analyzing the age and projected end-of-life of their capital systems and considering the benefits and costs of upgrades. 

Kosik: Maybe five years ago it was complex. With new products and standards as well as a better baseline understanding of energy and sustainability by our clients, we have been able to really push the envelope in coming up with novel design schemes.

Wesemann: I think it’s the issue that presents the most opportunities—solving challenges is the fun part of engineering. Manufacturers and engineers alike seem to be on board in developing new products and ideas to become more efficient.

Lane: Yes, new designs are driven by increases in efficiency. But, the key point is to increase efficiency without losing system reliability. One failure in a large data center can cost millions of dollars—far more than any savings from energy efficiency.

Dickens: Agree. The problem is that current sustainability and energy standards are aimed at buildings that are built for people, not process, and we have historically treated data centers as people buildings because of where they were and how they looked. Unfortunately, no clarity is on the horizon as ASHRAE concurrently tweaks Standard 90.1 to address data centers, and develops a new Standard 90.4P that will be specific to data centers. Doesn’t the fact that they are creating a new standard indict the current standard? What does a designer do in the mean time? That’s complex to say the least. 

CSE: With changing awareness of sustainability issues and increased number of products, has working on sustainable data centers become easier or more challenging?

Wesemann: The availability of products has definitely made it easier to select from more possibilities to meet energy-efficiency goals. As the newer products are implemented and get a track record, results (good or bad) can be shared in the industry, which helps everyone improve the next data center. 

Dickens: Both. The issue is easier to approach because the entire project team is aware of the challenge and in turn all can pull in the same direction with equal strength. But the products that we have at our disposal—the tools to measure success—are flawed and inappropriate for the application at hand. LEED v4 and the current version of ASHRAE 90.1 are tools that have been repurposed, but their adaptation is not consistently applicable. That’s why the goal should be to develop and use mission-centric goals and metrics instead of getting caught up in chasing plaques for the lobby. 

Kosik: It will always be challenging, no matter what. The challenge just shifts. Like right now, we are seeing clients requiring guaranteed PUE and energy performance. This ultimately becomes more of a financial and legal challenge than an engineering one, but it is a good demonstration of how energy efficiency is transforming the data center market from purely reliability-centered to energy efficiency and reliability focused.

Gillick: It has become more challenging—increasing the complexity of design review and lifecycle cost analysis, as well as the challenges associated with the integration, testing, and commissioning of the increasingly complex control systems for energy-efficient components, such as air-side economizer, photovoltaic, fuel cell, thermal storage, fuel oil, grey water, and mechanical systems. For example, it is not uncommon to defer testing and commissioning of the air-side economizer system for several months until outside air temperatures allow.

CSE: The U.S. Green Building Council recently released LEED v4, which includes more detailed information for efficient data centers. How do you think this will help with data center design?

Dickens: As an early adopter and advocate for LEED, I have been disappointed with the glacial pace of the revision process as it pertains to data centers. But we have to understand the challenges faced by the USGBC, especially because data centers are a niche market. Because I haven’t used it yet, I cannot speak to its efficacy, but overall it’s a positive development. There is a fear that the process of checking boxes and counting points may out muscle the intended goal of integrated sustainable design; but that’s a user issue, not a fault of the tool itself.

Gillick: Corporations will continue to seek LEED-certified design and commissioning of data centers, as it demonstrates their commitment to sustainability. However, I don’t anticipate that LEED v4 will make an appreciable difference in the MEP design of Tier III and Tier IV data centers due to their mission critical nature and associated utility requirements.

Wesemann: USGBC’s LEED process is well recognized in the industry as one way to score sustainability. Having data centers now as a category of LEED will most surely result in more discussions about energy efficiency during the design and ultimately lead to more sustainable data centers.

Kosik: Having been deeply involved in the development of the LEED credits written specifically around data centers, I know it will give designers more raw material to get the LEED process started for data centers, and not have to translate the commercial buildings credits so they can be used for data centers. Also, using the LEED rating system in conjunction with the ASHRAE 90.1 energy standard continues to build the industry’s tool kit for data center sustainability and energy efficiency.