It’s no secret that data centers are feeling the heat. With energy consumption and cooling systems accounting for a substantial portion of operational expenses, both legacy and new data centers are facing rising costs and mounting pressure to go green.
As server densities and heat loads continue to rise, data centers face an urgent and formidable challenge: how to keep servers cool, cut costs, and pave the way for even more future growth.
However, it’s not just about finding a way to lower temperatures – it’s about how efficiently your entire cooling system operates.
The Key to Energy Efficiency and Cost Reduction
Emerging conventional wisdom says the answer to rising heat loads either involves dispersing the offending servers or utilizing advanced technologies like liquid cooling and immersion cooling
Maybe. The first step really starts with airflow management.
Think of it this way: without proper airflow management, you’re essentially fighting against basic thermal dynamics. Heat moves from warm to cool areas, and once air is allowed to mix, the savings and value of any kind of cooling strategy or containment is quickly diminished.
While advanced cooling technologies are crucial, they must be built on the solid foundation of effective airflow management. Without it, even the most sophisticated systems can fall short, leading to inefficiencies and increased costs.
Poor airflow can also cause cooling systems to work harder than necessary, increasing energy consumption and wear and tear on equipment.
Airflow management done well can be surprisingly effective and extremely cost-friendly even with today’s heat loads. It’s the low-hanging fruit that you can tackle first, before investing in advanced techniques.
There are three killers of efficiency in data center cooling:
- Bypass Airflow: When cool air skips the servers and goes straight back to the cooling units because it escapes through cable cutouts, holes under cabinets, or misplaced perforated tiles.
- Internal Recirculation: When hot exhaust air in the rear of the cabinet gets sucked back into front of the cabinet and mixes with the cold supply air, creating hotspots.
- External Recirculation: When hot exhaust air from the server cabinet comes back into the server’s air intake from over, under, or around the cabinet.
Addressing these inefficiencies at the cabinet level is the first step toward dramatically improving a data center’s cooling efficiency.
In fact, the energy-saving benefits are so convincing, state and federal governments in the United States are increasingly requiring the use of airflow containment in data centers to mitigate energy consumption in one of the most energy-consuming environments.
“Containment, done with thought and planning, it absolutely works,” says Joe Loyer, a mechanical engineer at the California Energy Commission. “The question is not whether containment saves energy and money, but how much money it saves and how soon the return of investment can be realized."
As data centers expand, maintaining efficient airflow becomes even more critical. Properly managed airflow provides a scalable foundation that can support the integration of new technologies without exacerbating existing inefficiencies.
For the foreseeable future, we will likely see hybrid environments with both air-cooled devices and liquid cooling deployed where needed. That means airflow management is still one of the most important steps we can take.
Myths About Airflow Management
Air cooling is often underestimated because of several common misconceptions:
Myth 1: Airflow management and/or containment can’t handle today’s high-density loads.
Truth: The relationship between volume of air, heat load and temperature rise is often misapplied by considering the total temperature rise through the rack. The perceived limit to air cooling capability is based on how much air can be delivered out of a perforated access floor tile.
CFD models show that chilled air is consumed by the bottom half of the cabinet, creating hot spots at the top of the cabinet. Airflow management done well eliminates the dependency on chilled air from a perforated floor tile, and eliminates hot spots created by re-circulated air.
Myth 2: High-density airflow management techniques create unmanageable high return air temperatures.
Truth: Chilled water computer room air conditioners (CRAC) increase cooling capacity with higher return air temperatures. In instances when the return air temperature exceeds the cooling properties of economizer air, then a small amount of bypass air will suffice. Since the ideal embodiment of the passive cooling solution includes isolated return air in a ceiling plenum, bypass air may be delivered through an open ceiling grate, helping to regulate pressure in the room.
Myth 3: Lower acquisition costs for passive air solutions are overshadowed by higher operating costs than liquid cooling.
Truth: With the improved efficiency of a complete isolation between supply air and return air, close-coupled systems lose their operating cost advantage, and the total cost of ownership clearly favors the well-engineered passive cooling solution.
Mastering Effective Airflow Management
Properly controlling cooling doesn’t have to be a difficult task, and contrary to popular belief, it doesn’t require millions in investment either. In fact, it’s so simple, people most often overlook it.
Chatsworth Products takes a simple yet effective approach to airflow management. Our Passive Cooling® Solutions are innovative airflow management techniques that allow you to achieve 2-20+ kW of cooling without the use of mechanical cooling systems like fans, in-row air conditioners or liquid cooling solutions.
How Passive Cooling Works:
Passive Cooling is a tested and proven concept that leverages natural airflow, is eco-friendly and can be used in any Tier facility.
Summary of How Passive Cooling® Works: First, block bypass airflow and recirculation inside of your data center cabinets with important accessories such as Air Dam Kit and Snap-In Filler Panels, and more. Then, use the VED (Vertical Exhaust Duct) to guide hot air from the cabinet to a location high above the cabinet. The Vertical Exhaust Duct can be attached to a drop ceiling or a return air duct to create a closed hot air return to the primary air conditioning system or to vent hot air from the room. Once heat is removed from the room, ambient air temperatures are more easily controlled.
No more hot spots. No more recirculation. It almost sounds too good to be true.
While advanced cooling methods are valuable, they must be built on the solid foundation of effective airflow management. Overlooking this crucial aspect can lead to a domino effect of inefficiencies and increased costs. By first mastering airflow management, you set the stage for advanced cooling solutions to truly shine and drive sustainable, efficient, and reliable data center operations.
Watch the video below for a live demonstration of CPI's Passive Cooling® Solution operating at approximately 32 kW of IT load:
https://www.youtube.com/watch?v=FSo-rp7Wb0E
Maximize the Cooling Capacity in your Data Center with Better Airflow Management