Free cooling: The best solution for telecom shelters?

The electronic devices that sit at the heart of our telecommunication networks are incredibly reliable and robust, and this has only been enhanced over the years. The inherent redundancy of these networks also provides an extra layer of defense against any downtime occurring in these environments.

But, there are several dangers that place this equipment at risk, and overheating is one of the most prominent. Like any other computer or sensitive electronic equipment, telecommunications electronics need to be kept at fixed temperatures to operate optimally and last its lifecycle and prevent the possibility of this equipment failing due to excessive heat load.

Traditionally, telecom shelters have turned to traditional air conditioning units to overcome this critical problem, and a quality system will fulfil the role very effectively. However, then you encounter an issue that has become increasingly prevalent in the telecoms industry – high energy consumption.

Greater energy consumption means higher operating costs for telecommunication companies and, especially with the rollout of 5G commencing globally and the expenses behind this technology, businesses will be looking to find savings wherever possible.

Enter free cooling. Below we will explain why Dantherm’s free cooling solutions should be viewed as the first choice for telecom shelter operators and manufacturers ahead of the ‘conventional’ approach.

What is free cooling?

Free cooling harnesses the ambient temperature outside of the telecom shelter to deliver the necessary cooling inside, rather than use the compressor that is required in traditional AC units.

By harnessing the external air surrounding the shelter to provide the cooling, which 95% of the year will be lower than the typical 24ºC room temperature that a telecom shelter or data centre will be looking to maintain, you can provide cool, fresh air into the environment in a far more energy-efficient, simpler way.

There are two methods of free cooling – turbulent free cooling and displacement free cooling.

Turbulent free cooling

A turbulent free cooling system pushes and circulates the cool air from outside throughout the shelter before it is extracted, ensuring that it delivers the same cooling in every corner of the room.

This approach is preferable for larger, technical buildings with equipment that causes a high heat-load, making it crucial that the same heat is maintained everywhere. However, this comprehensive coverage means that it is the less energy-efficient of the two free cooling methodologies.

Displacement free cooling

Displacement free cooling is a very low-noise, low-cost approach to total heat management. By supplying the cool air at low speed to the bottom of the room, this forces the warmer air to rise up. This creates a cushion of cool air, with its centre at approximately 1.6m height of the room, where much of the telecommunications equipment is likely to be kept.

The warmer air at the top of the room close to the ceiling is then extracted to the ambient air outside the building by a damper.

As these units operate with low airflow and low fan speeds, as well as concentrate and limit the volume that is cooled, the energy consumption is considerably lower than the turbulent approach. However, there are limitations. As a displacement free cooling solution creates this cushion of cool air, it is not appropriate for large-volume shelters, and the position of the electronic equipment to be cooled needs to be adapted to this principle.

Nevertheless, more and more shelter manufacturers are designing smaller buildings around displacement free cooling units, making them the right size to benefit from this incredibly energy-efficient form of climate control.

What advantages does free cooling offer over traditional air-conditioning?

In most circumstances, free cooling delivers substantial benefits relating to the cost, operability and installation of these temperature control solutions when compared to the more commonly-known AC units.

Enhanced energy-efficiency

As we have highlighted already, by forgoing a compressor, the most energy-intensive component of traditional AC systems, free cooling solutions consume considerably less energy than these alternatives.

Depending on the location of the shelter and the climate surrounding it, a Dantherm free cooling unit can save a business between 60% and 90% of their current AC unit’s energy spend. With telecommunication companies compelled to find savings where possible as technology becomes more expensive, this reduced consumption can make a massive difference.

Overpressure of environment

Our free cooling units create an overpressure in the rooms that they operate in. This is beneficial as it means only filtered air ever enters the room – if there are any cracks or holes in the shelter or when opening the door, air will be blown out of this hole rather than anything being sucked in.

This is important as dust, sand, water and other particles can cause harm to the equipment in these rooms if it is allowed to enter. By providing this overpressure, it keeps all devices safe from these intrusions, going an extra step to protect them for the long term.

Ease of installation

Due to the involvement of compressors and refrigerant gases, a traditional AC system will need to be installed by a specially qualified technician. There are only a certain number of these technicians available, and they are naturally more expensive to hire.

Conversely, due to free cooling units not being reliant on refrigerant gases and overall having fewer moving parts than standard ACs, this makes the installation process far simpler and capable of being done by any capable technician. Installation becomes faster, less expensive and less complex.

Minimal maintenance demands

As an extension of this, the fewer moving parts behind free cooling solutions and their overall robustness mean that they are much simpler to service and maintain. Fewer components mean that there are fewer things that can go wrong, and our Flexibox’s long-life compact filter means that maintenance demands are kept to a minimum.

This can save your company significantly on the maintenance involved in your climate control system, and reduce the regularity of engineers coming to the site to resolve issues.

Supporting the design of shelters

With the bar for the technical design of telecom shelters and data centres significantly higher than it was 20 years ago, manufacturers of these structures need reassurance that their climate control solution will meet the specifications of their building. Dantherm’s free cooling systems provide that complete reassurance.

From meeting the fire classification standards, to enhancing the water-tightness of buildings by delivering a consistent overpressure into these rooms and efficiently filtering air inlet from sand, snow and dust with our patented air grilles, our systems are developed in accordance with the ever-evolving regulations that inform the construction of these shelters.

When do you need to use an AC solution?

As we have just established, when you have the choice between a free cooling solution and an AC unit, the former is the better way to go. However, free cooling is not applicable in every situation, meaning that you may be required to select an alternative or a complementary solution. There are two main reasons for this:

1. The ambient temperatures are periodically too high to achieve the maximum allowed room temperature

2. The size of the telecom shelter cannot contain a free cooling unit

Ambient temperatures periodically too high

Depending on the location of your telecom shelter, the climate could dictate that a free cooling solution alone is not possible. Free cooling is dependent on the ambient air surrounding the shelter being cooler than the temperature inside of it.

Most times of the year in most climates, this is absolutely the case. However, in areas that get particularly hot during the summer months, a free cooler would not work at these times. And, as the equipment inside needs to be kept at the appropriate temperatures all year round (it cannot take a summer vacation), a traditional air conditioner will be necessary.

Restricted size of the telecom shelter

With 5G telecom shelters/cabinets sometimes significantly smaller than most existing technical shelters (approximately no bigger than 1m³ in volume), this means they will not be large enough to facilitate free cooling technology.

In these circumstances, the typically more compact monoblock AC units will be capable of fitting inside these environments, so will need to be employed to keep the equipment cool.

The benefits of a hybrid system

If these limitations affect you, particularly the fluctuating climate around your shelter, we would recommend a hybrid solution, where you primarily utilise a free cooling solution, but can also activate an air conditioner when circumstances require it.

This gives you the best of both worlds. For the majority of the year, the lower ambient temperatures mean that you benefit from the greatly reduced energy costs, simpler maintenance management and diminished environmental impact of a free cooling system.

Then, if the ambient temperature does not allow free cooling, the AC unit can be activated as a backup solution, maintaining temperatures inside the shelter until the ambient temperature cools to a level where the free cooling system can resume.

Either solution can also be redundant to the other in case of failure on equipment. This makes a safe and very reliable solution in maintaining the necessary temperature in your shelters.

Maximise savings in your shelters with Dantherm free cooling technology

The nature of free cooling offers incredible opportunities for telecommunication companies to sharply reduce the operating costs of their technical shelters. If this applies to you, we hope this has illustrated that you have options over how to keep your equipment at the right temperatures, options that could save you a lot of money and hassle.

Dantherm’s free cooling units are at the forefront of this technology. We have researched and utilised these solutions for over a decade, with each new model being refined through years of accumulated knowledge.

• Extremely energy-efficient, with savings of up to over 90% depending on climate

• Total heat management, with complete control over multiple external units

• Overpressure system ensures clean indoor environments

• Flexible installation and low maintenance costs

• Remote monitoring and configuration offer maximum security for your system

Discover the advantages that free cooling by Dantherm can bring to your individual shelters and business overall – get in touch with our team for more information.