Telecom Cooling Solutions for Modern Infrastructure

This development presents a serious, not to be underestimated problem: heat.

The current 5G base stations use about 2 to 3 times less power than their 4G predecessors. This higher power consumption is directly converted into higher thermal output. The stakes are too high for the infrastructure managers and telecom engineers. Poor cooling causes thermal throttling, reduced life of the components, and worst, network downtime. Thermal failure is no longer an option in an industry in which five nines (99.999 percent) availability is the norm.

In this guide, this paper will explore the present state of telecom cooling and examine the technologies that are most appropriate to the infrastructure at hand, and how to optimize your thermal management strategy both in terms of performance and cost.

The Evolving Thermal Challenges in Telecom

It is important to comprehend the rationale behind the fact that the thermal profile of telecom equipment has evolved so drastically before choosing a solution.

Power density is the main motivator. Previously, the telecom equipment was accommodated in large switching centers where the CRAC (Computer Room Air Conditioning) units were huge. The network is becoming more and more dense today. Massive MIMO (Multiple Input, Multiple Output) arrays of antennas and Baseband Units (BBUs) are placing more processing units into smaller areas.

In addition, the place where the equipment is situated has been changed. The infrastructure is shifting to the edge, where it is situated in roadside cabinets, rooftops, and at the foot of cell towers. These sites do not have the clean environmental standards of a data center. They are subject to:

• Solar Loading: Direct sunlight increases the internal temperatures of the cabinet.
• Extreme High and Low temperatures: Nights of freezing, Days of scorching.
• Acoustic Constraints: Advice should be observed in the location of equipment in residential neighborhoods that would restrict the noise levels of the equipment so that the fan would be able to rotate aggressively.

Not only is it no longer a matter of keeping it cool but doing so efficiently, quietly, and dependably, in hostile places.

Primary Cooling Technologies: Air vs. Liquid vs. Hybrid

One method of cooling is better than another. The correct decision would largely depend on the heat load (in kW) and the physical location of the equipment.

Precision Air Cooling & Free Cooling

Air cooling is still the standard in use by a vast majority of telecom sites, especially those whose loads are less than 10-15kW each rack.

Precision Air conditioning: A closed-loop system (such as a CRAC unit) is used in this method to reduce the temperature mechanically. Although it works well, it is based on high-powered internal fans that are used to push this conditioned air past stacked density server racks and filters. It is stable and well known and is energy-consuming since the compressor is on throughout the time the fans are activated.

Free Cooling (Direct Air Cooling): To fight the excessive energy costs, Free Cooling has become the standard of the industry. In the case of this type of technique, external ambient air is used as a means of cooling the equipment when the outside temperature is colder than the internal setpoint. A smart controller opens dampers and activates high-efficiency intake and exhaust fans to force fresh air into the cabin, bypassing the compressor, which tends to burn lots of energy.

• Advantages: The use of fans instead of refrigeration could result in large amounts of OPEX savings (up to 40-50% energy savings in colder climates) by operating on fans instead of refrigeration.
• Disadvantages: Adds humidity and contaminants in case of poor filtration; does not work well in tropical climates.

Liquid Cooling (Direct-to-Chip & Immersion)

Above rack densities of 20kW (which occurs with edge nodes powered by AI), air ceases to effectively conduct heat. The new competitor is liquid cooling.

1. Direct-to-Chip (DTC): Cold plates are placed over hot components (CPUs/GPUs), and dielectric fluid is used to transfer heat.
2. Immersion Cooling: The server board is totally immersed in a non-conductive fluid.

The Reality Check: Although liquid cooling can be used to better transfer heat, it involves an extremely large-scale redesign of current infrastructure, which involves introducing plumbing, pumping, and other new maintenance procedures unfamiliar to many remote telecom sites. In the near future that is predictable, air-assisted hybrid solutions will be the most viable option as far as mass implementation is concerned.

Hybrid Cooling Strategies

Hybrid Cooling is the future to be realized by many operators. This strategy is based on air cooling most of the room or cabinet, but applies a localized form of liquid cooling (e.g., a rear-door heat exchanger) to certain high-density racks. This will enable the operators to increase the scale of 5G without foregoing their legacy investments in air-cooling.

In order to make you visualize the selection process, a comparison of typical use cases is given below:

Cooling Strategies for Outdoor Telecom Cabinets

The modern network frontline is the outdoor cabinet. It has no building shell to safeguard equipment, as is the case with a data center. The cooling policy in this case should be both defensive and functional.

Managing Environmental Factors (Dust, Moisture, and Heat)

Outdoor cooling systems are characterized by Ingress protection (IP) or NEMA rating. The construction of the cooling element, the fan in this case, is the most frequently weakest link.

1. Dust & Sand: Heatsinks and filters can be clogged by fine particulate matter in a desert or urban setting. Airflow resistance rises as filters are filled with dust. This requires the use of High Static Pressure Fans that can sustain a sufficient amount of airflow in clogged media without stalling or burning out.
2. Dampness and Salt Fog: Salt fog is murderous to coastal service. It causes copper plating and loss of normal fan bearings on circuit boards. The remedies to this problem are IP68 fans with fully encapsulated motors. These fans are hermetically sealed, unlike the normal coated fans, so that the inner electronics are never exposed to moisture as well as salt.

Active vs. Passive Cooling Methods

The consideration of active or passive cooling of an exterior cabinet is a computationalization of Δ T (delta T) – the discrepancy between the highest permissible internal temperature and the highest permissible exterior temperature.

1. Passive Cooling (Heat Exchangers/HEX)

This is the surest low-energy solution. It recirculates the hot air in the cabinet by an internal fan and blows the cool ambient air through a heat exchange core by an external fan. The two air streams never mix.

• The Fan’s Role: The cooling capacity of the system is propelled by the airflow volume of fans alone since the system does not have a compressor. The fans of high performance can promote the rate of heat removal of the traditional HEX unit considerably.

2. Active Cooling (Air Conditioners/TEC)

Active cooling is needed when the cabinet has to be in the sun, at 40 °C (104°F), and the equipment must be maintained at 25 °C (77°F).

Although active air conditioners are powered, they use strong condenser fans to give up the heat to the atmosphere. When such fans malfunction or wear out in adverse weather, the compressor will overheat and blow. Thus, the quality of the fans installed in the AC unit is a factor that is directly related to the quality of the AC unit itself.

The Role of Advanced Fan Technology in System Efficiency

No matter the type of Heat Exchanger you select, or a Precision AC unit or Free Cooling system, one element stands out as very important to the overall performance and effectiveness of the entire chain, and that is The Fan.

The fan is often regarded as a commodity; however, in reality, it is the heartbeat of the thermal system. In case the fan breaks, the cooling is interrupted, and the location becomes dark. When this fan is not efficient, then your PUE (Power Usage Effectiveness) shoots to the sky.

Why Fans Are Essential for Modern Telecom (ACDCFAN Solutions)

A generic off-the-shelf fan is hardly enough in the context of the modern telecom infrastructure. This is where specialized engineering comes into play in Total Cost of Ownership (TCO).

At ACDCFAN, we have realized that telecom clients experience three particular pain points, which include energy waste, harsh environmental conditions, extreme temperatures, and maintenance costs. The solution to these will involve abandoning regular AC fans in favor of more specific ones:

• Intelligent “On-Demand” Cooling (EC Technology):

  The conventional fans operate at full speed at all times. The EC (Electronically Commutated) fans of ACDCFAN are compatible with the PWM (Pulse Width Modulation) smart speed control. The fan will have contact with the system and will only rotate more quickly with the rise in heat load.

  • The Value: When the traffic load is low, the fans are slowed down, which minimizes power usage and noise significantly.
• Surviving the Elements (IP68 Protection):

  Normal fans do not last long when they are exposed to water or minute dust particles. In the case of outdoor telecom cabinets, we are using a special IP68 encapsulation procedure. This makes the motor and electronics totally resistant to the ingress of water and dust. Moreover, our designs are designed to perform well in extreme altitudes, when the air density is sufficient and sufficient cooling is obtained, unlike the normal fans that cannot perform in such conditions.

• Longevity as a Cost Saver:

  A change of fan that requires replacement in a distant mountain top cabinet may be expensive to the tune of half a thousand in truck rolls and man-hours. Reliability is paramount. With the help of the high-quality Dual Ball Bearing systems, our fans are able to reach an MTBF (Mean Time Between Failures) of more than 70,000 hours. This is an important feature of this install-and-forget reliability to minimize OPEX in remote infrastructure.

Thermal Management for Edge Computing Centers

The Edge Data Center is located a little further inward than the remote cabinet. These are containerized and prefabricated data centers that are placed nearer to the user to minimize latency.

Space is a luxury in such units. Large perimeter cooling units are out of the question. The fashion in this area is In-Row Cooling or Rear-Door Heat Exchangers. These are located between the server racks (or on the back part of these racks), reducing the airflow distance.

Hot Spots are also difficult to deal with in Edge centers. Due to the possibility of varying workloads on different racks (e.g., one rack is providing video streaming, another is providing IoT data), heat is produced unevenly. To manage all these micro-climates, smart thermal management systems should have sensors detecting them and target airflow at the location of need, another reason behind the intelligent PWM fans described above.

Optimizing PUE: Energy Efficiency in Telecom Infrastructure

PUE (Power Usage Effectiveness) is the ratio between the total facility energy to the IT equipment energy. A perfect PUE is 1.0. The older telecom locations are commonly operating at a PUE of 2.0 or greater; that is, every watt of electricity consumed in the transmission of data is wasted in cooling and lighting.

Minimizing the PUE is not only a matter of being green, but it is also a matter of profitability that can be minimized through maintenance. Cooling has been a typical component of 30-50% of a telecommunications site’s energy demand.

To optimize PUE:

1. Raise the Setpoint: Contemporary telecommunication equipment is durable. The internal temperature setpoint of 22°C can be increased to 26°C, and it can save colossal amounts.
2. Implement Airflow Management: Implement Airflow Management. Separate aisles of hot and cold to avoid mixing of air.
3. Upgrade to Variable Speed Components: Future change to variable speed compressors and fans assures you of only paying to cool as much as you are actually required at that point in time.

Conclusion

The move to the modern telecom infrastructure is a density management process. The higher the rate at which we are transmitting data using more advanced networks, the higher the thermal penalty. Regardless of the remote tower, which is managed by 5G or a containerized edge center, the aim is similar, i.e., reliability, efficiency, and longevity.

The budget might not be available to construct completely new facilities with liquid cooling, as is the case with many operators. It is at this point that retrofitting will be an effective strategy.

The whole cooling unit does not necessarily have to be replaced to achieve some benefits. Older cabinets can be given a new lease on life by upgrading the old systems with more modern High-Airflow Fan Trays or changing the AC fans in the cabinets with efficient EC-type equivalents. This micro-upgrade method addresses the short-term thermal concerns of the 5G equipment with the cost savings of a complete site upgrade.

ACDCFAN is here with you, should you be experiencing thermal problems in your deployment, whether designing a new outdoor cabinet or upgrading an old one with the old base station. We have our holistic range of AC, DC, and EC fans and robust ODM capabilities that allow us to give a preliminary cooling solution proposal within 10 days.

Telecom future is hot, but with the appropriate cooling plan, your telecom network will still be cool, efficient, and online.