Comparing Total Cost of Ownership (TCO) of High-Density IT Cooling Systems

Mike Schwarz, KlingStubbins

Presently there are multiple high-density information technology (IT) cooling technologies available to data center designers and owners. Steadily increasing IT loads have spawned many options for this cooling infrastructure, and developing and procuring an optimal solution can be a formidable process. Questions frequently arise when high-density IT loads are planned in new and existing data centers, especially in environments within larger buildings such as laboratories where space, power, or cooling may be constrained. However, when the system characteristics for a particular data center environment are scrutinized, and capital and operational costs are developed, the appropriate cooling system can be determined and optimized.

This presentation will include an independent review, from an engineering design perspective, of five different types of high-density cooling technologies and how they operate to support different IT architectures. System requirements, primary and secondary coolants, and the pros and cons of some typical installations will be discussed. Layouts of each cooling system when supporting a deployment of IT cabinets at different cabinet loads will be illustrated to review spatial, airflow, and redundancy requirements. In addition, the impact of implementing each system in existing and new data centers, including required mechanical equipment, mechanical/electrical utility distribution, reliability, and constructability will be summarized.

As an example of a holistic approach to energy-efficient and cost-effective data center design, the total cost of ownership (TCO) for each cooling technology at different IT load configurations will be compared. This is the life-cycle cost to the owner to build the system and operate it over time. Differences between metrics such as annual energy consumption, power utilization effectiveness (PUE), and cost/kilowatt of IT load for each system, and the related mechanical cooling plant(s) will be highlighted.

This presentation will provide attendees with a better perspective on how to properly compare high-density IT cooling options and apply them in their facility or next building project.


Mike Schwarz is a senior mechanical engineer and a young leader at KlingStubbins who is actively involved in technology for the conservation and reduction of energy use in buildings. His efforts are of significant consequence not only to the firm, but to the future of the built environment as we engage in the pursuit of achieving Architecture 2030’s goal of carbon-neutral buildings. Recently, Mr. Schwarz examined what steps would be required to meet near-term 50 percent carbon reduction goals using real-life building design projects nearing completion in the office as case studies.

During the past several years, he has become a key resource in the firm's energy and cost modeling efforts to test strategies for LEED® project certification and to reduce building life-cycle costs. He also mentors new engineers in this field of rapidly-increasing importance. Mr. Schwarz has pioneered the use of Computational Fluid Dynamics (CFD) airflow analysis within the firm and focused the use of this technology on dozens of mission-critical data center projects, as well as other building system applications. He has conducted research and presented on energy-efficient data center cooling systems at various national conferences, including 7x24 Exchange's bi-annual conference and the Labs21 Annual Conference.

Mr. Schwarz is a graduate of the Pennsylvania State University with a degree in architectural engineering.