4 Reasons IT Managers Should Consider In-Row Cooling for Small and Midsize Data Centers

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There are nearly 8,000 data centers globally as of January 2021, data from the Cloudscene reportOpens a new window of 110 countries reveals. This number is only set to grow substantially. According to the 2021 State of the Data Center reportOpens a new window by AFCOM and Data Center World, 48% of respondents plan to build additional data centers in the next 12 to 24 months, with 5% planning to build between six and nine.  

In addition to the exponential growth rate of data centers, the average server rack density is inching up, with nearly 50% of respondents reporting a shift towards powerful racks between 5kW and 10 kW, according to the 11th annual Uptime Institute Global Data Center Industry surveyOpens a new window , released in July 2021. 

But there’s another change underway. The traditional approach of concentrating all enterprise resources in a central location no longer works in an era in which computing power is expected to reside as close as possible to the users that require it. 

Edge and Small Data Center Is a Growing Trend

Traditional data centers have evolved from large full-sized facilities to small outposts at the edge. Massive amounts of data generated by next-generation applications have accelerated the need for faster processing power, performance, and security closer to the edge. With latency-sensitive applications becoming widely distributed, companies increasingly rely on edge deployments and small and medium-sized data centers to crunch data closer to the end-user. 

The rapid adoption of IoT also plays a big role as companies rush to move their compute, storage, and networking infrastructures to edge deployments. Uptime Institute’s annual 11th survey bears this out: More than 60% of respondents anticipate that edge computing demand will increase this year.

The migration of servers to the network edge is not a fleeting development. According to a recent IDC reportOpens a new window , 75% of organizations plan to increase their edge spending over the next two years, with an average increase of 37%. As a result, IDC projects global spending on edge computing to reach $176 billion by the year’s end. That’s an increase of nearly 15% over 2021. This upward trajectory is confirmed by STL Partners, who forecast the edge computing market to swell to $543 billion by 2030. 

Keeping Small Data Centers and Edge Deployments Cool

Edge computing sites range from ad hoc installations to dedicated deployments such as branch offices, warehouses or small retail locations. These remote edge deployments have a small footprint and often lack on-site technicians for monitoring and maintenance. The migration to the edge also signals a shift for IT and facility managers who need to reevaluate power and cooling architecture.

Often, edge deployments get upgraded, and more hardware is added in tightly packed server rooms. In such cases, facility managers and IT professionals need a reliable cooling solution that allows them to tailor the cooling infrastructure to the needs of server racks and effectively remove the heat build-up in mission-critical IT infrastructure.  

Although perimeter-based computer room air-conditioning units (CRAC) are touted as a standard go-to approach to reduce heat build-up from the higher density IT loads, this is only a short-term solution to what is a long-term problem for complex edge sites with a small footprint. In addition, the traditional perimeter-based CRAC solutions that use raised floors to supply cool air may not be a viable option for small facilities and won’t be able to deliver the paybacks in terms of energy efficiency.

Enter in-row cooling for small and highly densified data centers. In-row cooling units embedded between the rows are ideal for removing warm air generated from the back of rows and reducing air recirculation. Plus, it can directly impact energy costs and power usage. 

Thus, the shift of compute from large data centers to small IT installations has brought under the spotlight the need for efficient cooling solutions in small data centers where space is scarce. With server racks becoming denser, typically under 10 kilowatts (kW) per IT cabinetOpens a new window – IT managers must prepare to shift to alternate cooling systems to address growing heat loads and reduce power consumption. 

Perimeter CRAC vs. In-Row Cooling

Before we dive into the benefits of in-row cooling solutions, let’s understand the difference between perimeter cooling and in-row cooling systems. Perimeter CRAC cooling architecture is dependent on large condensers that utilize down-flow perimeter cooling units to distribute cold air beneath a raised floor supporting the server racks.  This cold air underneath is then directed towards the racks through perforated floor tiles. The cold air heats as it makes its upward trajectory until it returns to the cooling units, at which point it is cooled and then recycled downward once again in a rinse-repeat fashion. 

One of the problems with this vertical flow approach is the uneven distribution of cool air, which becomes exacerbated as rack height increases or a greater server density.  This is especially true of today’s hyperconverged infrastructure package appliances.  

In-row cooling solutions use a different architecture.  These units are positioned between the server cabinets and utilize a horizontal airflow pattern.  As a result, the cool air is produced directly beside the servers creating the heat. The cooling units draw the warm air exhaust air directory from the hot aisle, cool it, and then distribute it. 

While the advantages of this approach may not be as evident in large low-density data centers, one can see four distinct advantages that in-row cooling architecture brings to today’s edge computing and micro data centers.

Four advantages of in-row cooling:  

1. Maintain predictable cooling architecture

A ScienceDirectOpens a new window study showed that the perimeter architecture exposed inefficient cooling to the bottom of server racks due to the high momentum of the air leaving perforated tiles. This did not pose a problem with an in-row cooling approach as the cold air is more uniformly distributed along the racks’ height. The study also showed that in-row cooling was not affected by an increase in the racks’ power density, proving that in-row cooling is better suited for high power densities. Horizontal air flows are also less probable to recirculate throughout the physical space of the data center, thus allowing for a greater concentration of cooling power. 

This is where in-row cooling comes into play. Since the cooling units are placed between the rows and direct air to the loads, it minimizes the distance both cool and warm air need to travel.

Tripp Lite by Eaton’s line of easy-to-install in-row cooling unitsOpens a new window are designed to maximize cooling density and improve cooling efficiency, predictability and performance. Suitable for denser IT environments and power-hungry IT infrastructure, these units can be closely coupled to the racks, thus offering up to 50% higher coolingOpens a new window density over traditional perimeter CRACs. This means that in-row units take less power and energy to distribute cold air effectively.

2. Reduce footprint

It’s common for IT managers to squeeze more processing power into the existing space without increasing the footprint, which also significantly racks up power and cooling consumption. That’s why IT needs to look for modern cooling solutions that require less space and maintenance in small data centers and demanding edge deployments. Another key factor is that small data centers often lack a raised floor to accommodate a vertical flow cooling approach. Because of their horizontal airflow design, in-row cooling systems don’t require the overhead clearance needed for a conventional central air condenser. As these new data centers follow a modular design approach, it only makes sense that the cooling system does too.  

For instance, Tripp Lite by Eaton’s In-Row cooling unitsOpens a new window are perfect examples. With a slim profile of 300 mm, these lean but powerful cooling units can boast 88,000 BTU/hr Opens a new window of high-precision in-row cooling power. The compact design gives IT managers more room for mission-critical equipment such as servers or storage gear. It also enables them to keep up with the ever-evolving facility, a crucial factor in edge sites and small data center design. Additionally, the outdoor condensers can be placed either on rooftops or yards, allowing IT to conserve floor space in small data centers. 

3. Lower energy costs

So far, we’ve learned that the smaller distance equates to greater efficiency and allows for smaller cooling fans. It also translates into reduced energy consumption which means lower energy costs. Research shows that in-row cooling platforms that direct cool air straight to the IT workloads result in energy savings of 25% over traditional perimeter CRAC unitsOpens a new window . 

Meanwhile, ScienceDirect’sOpens a new window cost comparison study between perimeter and in-row cooling architectures was conducted mathematically. The equation included an energy utilization coefficient that indicates the percent that the observed racks benefited from the cooling capacity of the cooling units. An increase in the coefficient value represents less wasted cooling energy. The performance of perimeter cooling architecture was 1.4, while in-row saw a higher reading of 1.9. 

In short, leveraging in-row cooling units result in substantial energy cost savings and lower total cost of ownership compared to traditional perimeter-based cooling.  

4. Continuous power availability

Today’s data centers must have built-in resiliency to service mission-critical workloads. Traditional perimeter cooling systems are dependent on large condensers that serve as an obvious point of failure, and redundancy is an expensive option. Organizations need to spend on IT personnel to maintain these systems, which can present fresh challenges and swell operational expenses.  

Tripp Lite by Eaton’s in-row cooling solutionsOpens a new window provides far greater resilience because the units work independently of one another and can easily be swapped out in the event of failure by regular IT personnel. Unlike a traditional air condenser, the affordability of these units allows companies to support an N+ configuration model so that a spare can be available quickly. 

Closing Thoughts

The shift to the edge and small data centers requires a new cooling methodology. Tripp Lite by Eaton’s in-row cooling system is designed for today’s small to midsize data centers, modular server rooms and edge-based locations. With advantages such as a compact and versatile footprint, enhanced cooling efficiency, inherent design resiliency and reduced energy costs, these in-row technology alternatives are the perfect solution for this new modern era of data center design. 

Take a closer look at how Tripp Lite by EatonOpens a new window can meet the cooling needs of your data centers today.