HVAC Cooling System Considerations

In the age of Artificial Intelligence, HVAC systems for data centers play a crucial role in keeping servers cool and running optimally. Due to the significant heat rejection from high-density server operations, HVAC systems of the ’20s have had to evolve rapidly. When one considers the accommodation of local humidity levels and the advanced filtration needs of emerging technologies, the HVAC system selection process becomes increasingly intricate. A foundational understanding and consultation with mechanical engineering specialists are paramount to ensuring the efficacy and success of cooling your building project.

The most common cooling techniques found in data centers are:

• Air Conditioning: Traditional systems use raised floors with computer room air conditioners (CRAC) or computer room air handlers (CRAH) units to manage air temperatures, expelling hot air while introducing cooled air. Suitable for smaller data centers, these systems struggle with high-density loads and can incur substantial energy costs.
• In-Row Cooling: In-row cooling affixes units directly next to or in between the server racks, providing more targeted cooling.
• Liquid Cooling: Liquid cooling systems use a liquid coolant to absorb heat directly from servers. This approach is considered more advanced and efficient for managing server room environments.
• Free Cooling: Free cooling leverages outside air to cool data centers, reducing energy consumption. It is highly dependent on the climate zones where the data center is located, and it is particularly effective in colder climates or predominantly dry climates where ambient air (OA) has lower dew-point conditions. This allows for harnessing evaporative cooling effects to enhance overall cooling efficiency.
• Hot Aisle/Cold Aisle Configuration: This design approach separates hot and cold air aisles, optimizing airflow and improving cooling efficiency.
• Rear Door Heat Exchangers: These devices attach to the rear of server racks, removing heat efficiently.
• Immersive Cooling: Submerging servers in a liquid coolant maximizes heat dissipation, offering efficient thermal control.

As technology evolves, new techniques continue to emerge to enhance cooling efficiency and sustainability.

When constructing new data centers or renovating existing ones, accurately assessing both current and future operational requirements is crucial for success. During the initial project design phase, integrating a variety of systems, such as air-cooled systems, alongside advancing technologies like liquid cooling, direct-to-chip cooling, and single-phase or two-phase immersive cooling is essential. Understanding these dynamics ensures alignment with current technological trends and effectively prepares for future demands.

Selecting the best cooling method for a data center is a highly customized process that begins with acknowledging that there is no “one-size-fits-all solution” and typically involves considering the following factors:

• Server Design: Understand how your servers are designed to be cooled. Some servers are designed to be air-cooled, while more modern servers are meant to be cooled off using liquid cooling technology.
• Energy Efficiency: Compare and evaluate the energy efficiency of different cooling methods. Liquid cooling tends to be more energy and space-efficient but requires additional infrastructure and a certain server design.
• Space Constraints: When evaluating cooling options, carefully consider the available space within your data center. Innovative and compact solutions such as “In-Row Cooling” and “Rear Door Heat Exchangers” should not be overlooked.
• Costs: Compare First Costs + Operation Costs (Installation, Maintenance, and Energy Consumption) – Air cooling may often appear more affordable as far as the first costs go, but liquid cooling may save costs in the long run.
• Environmental Factors: Assess the local climate. Analyze which “Free Cooling” features may be available and compatible with the project’s needs, taking into account the specific characteristics of the climate zone.
• Scalability: A modular design is always desirable, considering the potential for future growth and expandability of nearly any data center.

These factors collectively underscore the intricate nature of selecting an ideal cooling solution tailored to each data center’s unique needs. By meticulously assessing various constraints, such as environmental influences and spatial limitations, data center operators can make informed decisions that optimize performance, reduce operational costs, and enhance sustainability. Each consideration plays a crucial role in ensuring that the chosen cooling method not only meets current demands but also positions the data center for future success in a rapidly evolving technological landscape.

WGI’s Value

At WGI, our MEP experts are leaders in designing and implementing traditional HVAC and cutting-edge cooling solutions. We combine innovative technologies with a steadfast commitment to sustainability, efficiency, and creativity, ensuring that your data center not only achieves optimal thermal management but also prepares for future advancements with resilience and efficiency.

This is just Part One of our exclusive three-part series on Cooling Down AI & Data Centers. In Part Two, we’ll dive deep into the innovative realm of liquid and immersion cooling systems, unveiling insider secrets that are transforming data center cooling practices as we know it – So, stay tuned!

• Cooling Down AI & Data Centers Blog Series:
  • Part 1: Introduction to Cooling Systems
  • Part 2: Introduction to Liquid Cooling Systems
  • Part 3: Direct-to-Chip Cooling (Coming Soon)

Contact Us

Ready to transform your data center’s cooling efficiency? Contact us today and discover how our team of experts can help you stay ahead of the curve with innovative and sustainable solutions. Let’s turn your cooling challenges into a breeze!