Data Center Cooling

We've all been hearing more and more about artificial intelligence in recent years, whether in the news, at our jobs and everywhere in between. Similarly, you've probably also been hearing more and more about data centers.

That's no surprise, as data centers are major facilitators of the rise of AI capabilities and use cases.

From a financial perspective, revenue from data centers is projected to exceed $452 billion in 2025, according to one estimate, and soar to $624 billion by 2029.

In short, there's a lot of money involved and a lot of high-priced technology making it all happen, not to mention energy. According to one forecast, data centers could account for 3-13% of global electricity usage by 2030, up from around 1% in 2010.¹

Just as the data center market is heating up, the technology powering all of it heats up, too (literally). These applications require cooling, or you have significant problems on your hands if you're a data center manager or an application depending on data centers.

Just like your car's engine or your laptop computer, data centers need to keep cool.

Data centers are booming.

A quick search in the search engine of your choice — searches that are supported by data centers, by the way — will turn up headline after headline touting the rise of data centers around the world. In short, data centers are facilities that will help power the world's digital transformation, which includes artificial intelligence (AI).

But what are data centers, exactly?

Think of data centers as the beating hearts of our digital world – massive facilities that pulse with the constant flow of information. Just like a bustling city never sleeps, these technological powerhouses operate 24/7, housing thousands of servers, storage systems, and networking equipment that keep our emails flowing, videos streaming, and online shopping carts filled. They're integral pieces of our everyday lives, whether we think about them or not.

At their core, data centers are purpose-built facilities designed to provide a controlled environment for IT infrastructure. They're the invisible backbone supporting everything from your morning weather check to complex financial transactions happening across the globe. Picture a warehouse-sized building filled with rows upon rows of server racks, each one humming with activity like a well-orchestrated symphony.

These facilities range from small server rooms in office buildings to hyperscale operations spanning multiple football fields. Major tech companies like Google, Amazon, and Microsoft operate colossal data centers that consume as much electricity as small cities. Each rack contains servers that work together, processing and storing the enormous amounts of data generated every second by billions of connected devices worldwide.

Data centers also serve as the foundation for cloud computing services, enabling businesses to store data and run applications without maintaining their own physical hardware. They're equipped with redundant power systems, advanced security measures, and sophisticated monitoring tools to ensure continuous operation.

Without these critical facilities, our interconnected digital lives would simply cease to function, making them as essential to modern society as power plants or water treatment facilities.

Imagine your laptop getting warm during heavy use. Many laptops feature built-in fans that you might hear switch on when your computer starts to get too hot.

Now multiply that heat by thousands.

Data centers face the same challenge on an enormous scale, where the collective heat generated by countless servers can quickly transform these facilities into digital furnaces without proper cooling systems. Overheating can lead to performance failure, hardware damage and costly downtime.

Every piece of electronic equipment in a data center generates heat as a natural byproduct of electrical resistance. When electricity flows through processors, memory modules, and storage devices, energy converts to heat just like a toaster warming your morning bread.

In a typical data center, this heat generation is relentless – servers don't take coffee breaks or clock out for the day, meaning heat production never stops. So, the need for efficient cooling processes in data centers is basically ever-present.

The consequences of inadequate data center cooling can be catastrophic. Here's what can happen:

Electronic components have optimal operating temperature ranges, and can experience performance loss or outright failure if temperatures move outside the recommended range. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), which has been producing thermal guidelines for data centers since 2004, offers a recommended temperature range of 18-27℃ (64-81℉) for maximum uptime and hardware life, although broader "allowable" guidelines indicate ranges at which operations can be expected to continue When temperatures exceed these thresholds, servers can begin to throttle their performance to prevent damage, much like how your car's engine might limit power when overheating.
In extreme cases, critical hardware can fail completely, leading to service outages that affect millions of users and cost companies hundreds of thousands of dollars per hour.
Heat also accelerates component degradation, significantly reducing the lifespan of expensive server hardware. Additionally, modern data centers pack equipment into increasingly dense configurations to maximize space efficiency, creating hot spots that can develop rapidly if cooling systems can't keep pace.

Effective cooling isn't just about preventing failures in data centers. Data center cooling means:

Maintaining optimal performance
Extending equipment life
Ensuring the reliability that users expect from digital services
Reducing operational costs (i.e., energy) via more efficient and effective cooling strategies

Smart data center cooling requires strategic planning and consideration of both passive and active design of cooling systems.¹

Here are a few best practices to consider when it comes to optimizing a data center cooling strategy:

Hot Aisle/Cold Aisle

Hot aisle/cold aisle containment represents the gold standard of cooling design. Picture grocery store freezer aisles with doors – this setup creates distinct pathways where cold air flows to server intakes while hot exhaust air gets captured and directed back to cooling units. This prevents the wasteful mixing of hot and cold air that plagued older data center designs, much like closing your refrigerator door quickly to maintain efficiency.

Temperature/Humidity Monitoring

Temperature and humidity monitoring requires sensor networks throughout the facility, creating a real-time map of environmental conditions. These systems work like a smart thermostat on steroids, automatically adjusting cooling output based on actual needs rather than guesswork.

Just like other facility types, data centers have ideal ranges for a important specifications like temperature and humidity. If a data center is outside the recommended range for either, equipment failure can result.

ASHRAE's recommended temperature is 18-27℃ (64-81℉), while its "allowable" range is slightly more forgiving. As for relative humidity, the recommended range is 45-55%, with a wider "allowable" range of 20-80%.

ASHRAE and other organizations like it update their guidelines over time, so it's advisable for operators to check in to see what the latest recommended ranges are. AHSRAE's page for data center guidelines can be found on its website.

Airflow Management

Airflow management involves eliminating obstructions and optimizing pathways, similar to organizing your home's furniture to maximize air conditioning effectiveness. Perforated floor tiles, cable management systems, and strategic placement of cooling units ensure air reaches where it's needed most efficiently.

Regular Maintenance

Regular maintenance schedules keep cooling systems running at peak performance. This includes cleaning air filters, checking refrigerant levels, and calibrating sensors – routine tasks that prevent small issues from becoming major failures. Energy efficiency improvements often focus on raising operating temperatures slightly within safe ranges, using variable-speed fans, and implementing intelligent controls that adapt to changing server loads throughout the day.

Data center cooling techniques range from traditional air conditioning systems to innovative approaches that seem borrowed from science fiction. Each method offers distinct advantages depending on facility size, climate, and operational requirements.

In terms of active design, the following are examples of the most prominent forms of data center cooling in use today.

Air-Based Cooling

Air-based cooling remains the most common approach, using computer room air conditioning (CRAC) units that function like industrial-strength versions of your home's central air system. These units circulate chilled air through raised floors or overhead ducts, maintaining consistent temperatures across server racks.

Precision air conditioning provides tighter temperature and humidity control than standard HVAC systems, essential for sensitive electronic equipment.

Liquid Cooling

Liquid cooling systems pump coolant directly to server components, much like a car's radiator system keeps engines from overheating. Direct-to-chip cooling uses cold plates mounted on processors, while immersion cooling submerges entire servers in non-conductive fluids. These techniques can remove heat far more efficiently than air cooling, enabling higher-density server configurations while reducing energy consumption.

Free Cooling

Free cooling leverages outside air when environmental conditions permit, similar to opening windows on cool days instead of running air conditioning. Economizer systems automatically switch between mechanical cooling and filtered outside air based on temperature and humidity readings. This approach can dramatically reduce energy costs in suitable climates.

Evaporative Cooling

Evaporative cooling uses water evaporation to reduce air temperature, employing the same principle that cools you down when perspiration evaporates from your skin. Indirect evaporative coolers provide cooling without adding humidity to server areas, making them suitable for dry climates where traditional air conditioning would be less efficient.

Each technique can be combined in hybrid systems that optimize performance while minimizing energy consumption and operational costs.

The future of data centers and data center cooling looks like a fascinating blend of cutting-edge technology and back-to-basics environmental awareness, much like how electric cars represent both high-tech innovation and a return to cleaner transportation methods.

Artificial intelligence and machine learning are revolutionizing cooling management by predicting heat loads and automatically adjusting systems before problems develop. These smart systems learn from historical patterns and real-time data, optimizing cooling efficiency like a chess grandmaster thinking several moves ahead. Google's AI-powered cooling systems have achieved up to 40% energy savings for cooling operations by continuously fine-tuning thousands of variables simultaneously, with performance improvements reaching 30% over time.

Immersion cooling technology is expanding beyond experimental installations into mainstream deployments. Future data centers may resemble giant aquariums more than traditional server rooms, with entire racks submerged in specialized cooling fluids. This approach eliminates fans and traditional air conditioning while enabling unprecedented server density and energy efficiency.

Edge computing is driving the development of micro-data centers that require innovative cooling solutions for diverse environments. These smaller facilities might operate in retail stores, cell towers, or even outdoor enclosures, demanding cooling systems as adaptable as a Swiss Army knife.

Sustainability initiatives are pushing the industry toward renewable energy integration and waste heat recovery. Future data centers will capture and redirect waste heat to warm nearby buildings, greenhouses, or industrial processes, transforming what was once an unwanted byproduct into a valuable resource.

Quantum computing and advanced chip architectures may eventually require exotic cooling methods, including cryogenic systems that operate at temperatures approaching absolute zero. As computing continues evolving, cooling technologies must adapt to support increasingly powerful and efficient hardware while meeting growing environmental responsibilities.

The importance of data centers in all of our lives is set to increase manifold in the years ahead.

But the digital transformation being facilitated by data centers cannot happen without proper cooling. Just like your car, your laptop computer or even your old video game console that somehow still works, data centers need effective cooling strategies in place so the IT equipment therein can continue to do its job.

There are many strategies out there aimed toward data center cooling. At Dober, we've developed a heat transfer fluid product for liquid-cooled systems, particularly with the high cost of air cooling in mind.

Visit our dedicated page to learn more about COOLWAVE DC, our propylene-glycol-based coolant formulated for optimal data center cooling needs.

Citations

1. Andrae, A. S. G., & Edler, T. (2015). On Global Electricity Usage of Communication Technology: Trends to 2030. Challenges, 6(1), 117-157. https://doi.org/10.3390/challe6010117

2. Senhong Cai, Zhonghua Gou, Towards energy-efficient data centers: A comprehensive review of passive and active cooling strategies, Energy and Built Environment, 2024, ISSN 2666-1233, https://doi.org/10.1016/j.enbenv.2024.08.009. (https://www.sciencedirect.com/science/article/pii/S2666123324000916)

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