Electrical standards for data center cooling systems
Data center cooling systems are a significant driver of electrical energy consumption. Regardless of which cooling method is used, choosing components rated for industry electrical standards promotes thermal efficiency and helps drive down PUE.
Today, an estimated 2 – 3% of global grid power is consumed by data centers, and experts predict that percentage may rise as capabilities such as Artificial Intelligence and Machine Learning drive demand even higher. Grid expansion can be a long, expensive, and legally challenging endeavor, so data center developers and operators are often under immense pressure from local governments, utilities, the media, and the public to be ever-more energy efficient.
Of the electrical energy consumed by a typical data center, 20% is spent on basic electrical needs, i.e., “keeping the lights on.” The remaining 80% is split relatively evenly between cooling systems and IT equipment. In this article, we will dive into energy efficiency in data center cooling systems and how choosing components rated for energy efficiency is critical to achieving Power Usage Effectiveness (PUE) targets.
How data centers keep their cool
HVAC systems (air conditioning) are a cornerstone for data center cooling. Air conditioning is highly energy efficient in cooler climates where these systems don’t need to work as hard to cool the indoor environment. HVAC systems are also well understood and easy to maintain. In brownfield data center development, air conditioning may also have the advantage of already being installed, lowering the cost of development and allowing faster commissioning.
Despite their longevity, HVAC systems have advanced over the years. Most recently, the industry switched to A2L refrigerants to reduce the use of hydrofluorocarbons (HFCs) that can contribute to global warming. While still rated as low flammability, A2L is slightly more flammable than the older refrigerants typically used in commercial HVAC systems.
When HVAC systems aren’t enough, liquid cooling can be used to remove excess heat from computer systems and infrastructure equipment by using a liquid heat transfer medium. This method is more efficient than traditional HVAC cooling because liquids have higher heat capacities and can transfer heat more effectively. While liquid cooling is more expensive to implement, it is ideal when Power Usage Effectiveness (PUE) targets are a priority.
Standards for cooling system safety and efficiency
Safety remains a critical requirement in data centers. In addition, since cooling systems consume roughly 40% of the energy used in a typical data center, choosing electrical components that meet energy efficiency standards is also critical.
UL 60335 is a series of safety standards for the performance and safety of electrical appliances. UL 60335-2-40 focuses on the safety requirements specific to HVAC systems, addressing the testing and certification requirements for potential safety risks such as the flammability of refrigerants. The liquid used for data center cooling is often water or a water/glycol mix, so UL 60335 is not applicable.
Minimum Energy Performance Standards (MEPS) standards set specific performance thresholds for the efficiency of energy-consuming systems. In data center cooling, MEPS typically apply to components such as electric motors, pumps, fans, and compressors. Choosing components that adhere to MEPS standards can help drive down the data center’s PUE ratio. These standards can vary from region to region, but ABB’s energy efficient motors are designed and labeled to comply with international IEC standards and local MEPS requirements.
The IE3 and IE4 motor efficiency standards, which define different levels of efficiency for electrical motors, are a prime example of a MEPS standard that is widely recognized. IE3, known as “Premium Efficiency“, represents a higher standard of energy efficiency compared to IE2, the previous “High Efficiency” benchmark. IE4, classified as “Super Premium Efficiency”, denotes an even higher standard of energy efficiency, characterized by further reductions in energy consumption and operational costs.
NFPA 79 was developed by the National Fire Protection Association (NFPA) to provide comprehensive guidelines for the electrical systems of industrial machinery, focusing on ensuring safety from electrical hazards. The standard covers aspects from design and installation to maintenance and operation of the electrical equipment used in machinery.
UL 508 is an industry standard that covers industrial control devices and
components used for starting, stopping, regulating, controlling, or protecting electric motors. The standard is designed to ensure these components are built to safeguard against fire, electric shock, and injury. Examples of components that fall under the UL 508 standard include manual and magnetic motor controllers, motor control centers, relays, pushbuttons, and selector switches. UL 508A supplements UL 508 and focuses on industrial control panel design and construction to ensure recognized safety standards are met.
UL 67 and UL 891 share a focus on safety and performance, and both play an important role in power distribution within industrial settings, such as data centers. UL 891 covers dead-front switchboards, which are designed with no live parts exposed at the front and suitable for up to a maximum of 1,000 V with the use of UL 489 circuit breakers or UL 1066 circuit breakers. The UL 67 standard applies to panelboards, which are generally smaller than switchboards and used primarily in lower-ampacity applications. To learn more, read “UL Product Standards for Switchboards and Panelboards”.
Balancing consumption with sustainability
Optimizing energy efficiency in data center cooling systems is critical to balancing the demand for increased computing capacity against available electrical power. Successfully balancing competing demands will go a long way toward sustaining the data center industry through the challenges of grid limitations and environmental concerns. Achieving an optimal PUE can also help data centers become a welcome addition to the community as regulators and residents grow in confidence that the data center will benefit the community instead of competing with it for limited power resources.
As stakeholders in a digital future, ABB fosters a commitment to efficiency through technological advancements and adherence to industry standards. We demonstrate our commitment by developing power components solutions for HVAC cooling systems and liquid cooling systems that are energy-efficient, designed to withstand the rigors of data center use, and adhere to the latest efficiency standards. To learn more about our solutions for data center cooling, we invite you to visit our website: Data Center Cooling Technologies.
See related blog post “Actionable strategies for data center cooling efficiency and sustainability.”
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Will Hulbert
Product Marketing Manager
Matt Darroch
Product Marketing Manager for Pilot Devices, Electronic Relays & Controls, Limit Switches
