Keeping the air pristine inside data centre facilities is key to operating at full proficiency and protecting electronic equipment. Operators must balance this with minimising HVAC energy use which increases greenhouse gas emissions. Tony Abate, Vice President and Chief Technology Officer, AtmosAir Solutions, discusses one way to achieve both.
The increased need for building new data centres – and upgrading existing ones – to meet the demands of AI is putting a new emphasis on utilising technologies to make them perform more efficiently and sustainably. AI requires more data processing capacity, high computational power and continuous operation. All of this adds up to more data centre capacity, more square footage and more machines operating.
It’s been said many times before that data centres have become essential to our modern lives. Think of all the things you touch daily that are transmitted to cloud-based services all of which have servers housed in data centres. PCs or laptops, smartphones, smart doorbells and even your car send and receive data from a centralised location.
As such growth and demand for data centres is unprecedented. According to McKinsey, the data centre market is expected to grow from a current demand of 25GW in 2024 to 80GW by 2030. To put some perspective here, 1GW is equal to one billion watts. A power plant with 1GW could power 876,000 homes for one year. Data centres will consume significant power and the need to build new facilities and improve older ones will grow significantly.
These data centres will need more power not just to operate the machines but also the facility. A major factor in these large square footage buildings is HVAC (Heating, Ventilating and Air Conditioning).
Look at the bigger picture
There are two major HVAC considerations that will help make data centres perform better. One is sufficient cooling capacity; the machines generate heat, and cooler temperatures are needed. Data centres with high-density servers need to maintain temperatures between 64-72F to ensure the chips in the machines don’t overheat, which will impede their performance and lead to failure. This can have a catastrophic effect in data centres, where most machines are relied on to operate continuously.
The importance of air quality
Conditioning outside air is a significant factor in any building where temperature control is critical. This is where most HVAC energy is used. Utilising strategies to limit outside air introduction is critical to improving energy efficiency in a data centre.
Dust particles can be introduced from outside or within the building can build up on servers and hinder cooling, leading to equipment failure. Also, gaseous contaminants such as sulfur dioxide and hydrogen sulfide can be corrosive and damage servers. Typical measures taken to reduce these contaminants are increased outside air to dilute gaseous contaminants or activated carbon filters to absorb these gases. Media filters to address fine dust particles are typically MERV 11 to 13 and many facilities use multistage filtration with pre-filters and final filters that can be up to HEPA efficiency. High-efficiency filters will restrict airflow making cooling more difficult and more power is used.
Cleaner and greener energy
Data centres have considerable challenges. Only 20% of electrical power available is from a sustainable source, such as solar, wind or hydropower, according to the Office of Energy Efficiency & Renewal Energy. Given the high-power demand of data centres, how can they operate more sustainably?
Some have employed strategies like solar panels on roofs, given the large footprint of these facilities, which can generate sustainable power. There are also many opportunities to decrease the power demand to condition the facility. Limiting outside air introduction can have a major effect on reducing power demand. Also, less outside air will reduce contaminants like PM 2.5 particles that need to be filtered.
Implementing strategies to use advanced air cleaning technologies, such as bipolar air ionisation can clean air, reduce particles and gaseous compounds, and allow the building to re-circulate more air that has been conditioned to temperature and use significantly less energy. Also, enhanced air cleaning as described above can lessen the need for high-efficiency media filters. Using a lower MERV-rated filter will reduce airflow restriction, reducing fan horsepower needs from HVAC equipment and producing better airflow for much-needed cooling. These effects will both result in lower power demand.
In particular, bipolar ionisation technology causes a gas phase breakdown of gaseous contaminants, reducing these potentially corrosive elements and causing particles to agglomerate, becoming bigger and heavier, where less efficient filters can capture them better. Another benefit of this technology is the neutralisation of static charge, as the technology produces both positive and negative ions as found in nature. This neutralising of static will keep dust particles from collecting on servers and allow them to operate cooler and more efficiently.
All these options reduce the need for power and decrease the carbon footprint of the facility, helping to meet sustainability goals.
Monitor to minimise
Today, many buildings monitor indoor air quality in real time to operate more efficiently and sustainably. Understanding CO2 levels can guide a facility to make automated adjustments to outside ventilation. Tracking particle levels can help the facility use performance-based maintenance, such as filter replacement based on IAQ data, rather than prescriptive maintenance based on the calendar.
Even as the demand for data centres grows and the power needed to operate them increases, using creative strategies like advanced air cleaning and air monitoring can help minimise energy use from the facility and improve sustainability and the impact on the environment.
