The rapid acceleration of global digitisation is being fuelled by business and consumer demand.
Today’s economy runs on digital infrastructure and global tech giants like Meta, Amazon and Google would simply not exist without these digital networks. Of primary importance now is that this exponential growth does not negatively impact global efforts to reduce climate change.
In response, the data centre industry is prioritising the introduction of new and emerging ‘green’ technologies. While in Europe, data centre operators and trade associations have committed to the Climate Neutral Data Centre Pact, which is steering the industry towards carbon neutrality by 2030.
Progress has so far been rapid with companies ramping up investment in clean and renewable energy sources, limiting or redeploying waste by-products, and improving their power usage effectiveness (PUE). However, to meet the end of decade target, the industry must maintain this momentum and continue to develop new technologies and deliver long term sustainability practices.
Looking to the long term
Significant headway has been made by the introduction of low carbon energy sources that have enabled the industry to scale with rising data volumes without increasing emissions. By prioritising virtual power purchasing agreements (VPPAs), the industry is now able to buy significant levels of renewable energy coverage within their local markets, helping them to ‘green the grid’.
Expanding the use of renewable and low carbon energy is crucial to reducing the industry’s carbon footprint. Bridging technologies will make it possible to replace fossil fuel diesel generators with renewable HVO fuels, based on vegetable oil, in the intermediate term.
In the longer term, the industry may shift to completely new energy systems based on hydrogen fuel cells, currently being developed by the Clean Hydrogen Partnership. These could eventually replace diesel generators with a clean energy source, thus reducing harmful emissions, lowering costs, and making data centres easier to deploy in populated areas. Other clean energy technologies are also being explored. Equinix is currently working in partnership with Bloom Energy to test solid oxide fuel cells as a potential replacement for traditional diesel generators and uninterruptible power supply (UPS) units.
Regarding energy efficiency, it is important to understand exactly how much energy data centres use and where efficiencies can be gained. By leveraging AI algorithms, automated data centres can track energy usage and optimise their operations, such as analysing airflow and reducing unnecessary cooling, as well as schedule workloads based on renewable energy availability. By deploying a software-defined power management solution, operators will be able to manage power draw and limit power stranding to nearly 0%, improving powering efficiency in certain data centres by as much as 30-50%.
Using energy more efficiently is critical to meeting the industry’s carbon neutral goals. This efficiency is measured using power usage effectiveness (PUE) – comparing the total energy used by a data centre with the portion used specifically for IT equipment. To reduce PUE, operators must decrease overhead energy that does not directly power IT equipment. It is estimated that 75% of that additional energy goes toward cooling systems, which is why high-efficiency cooling is set to play a critical role in the sustainability equation.
Liquid cooling
One solution is liquid cooling, a process that is able to maintain stable equipment temperatures where traditional air cooling may fall short. The industry is now seeing considerable investment, research, and the establishment of ecosystem partnerships to drive forward these cooling technologies.
Liquid cooling allows data centres to run warmer, meaning less use of refrigerants or evaporative cooling. Generally, data centres run warmer today than they did 20 years ago, and the sector will continue to increase temperatures as server technology improves. This means it will become possible to turn off air conditioning units for most, if not all year long. Equinix is one of a number of companies exploring this area and has partnered with liquid cooling company ZutaCore to test and develop highly efficient rack systems that can cool 100 kW or more per rack with a compact, waterless design.
However, liquid cooling adoption requires collaboration between the hardware manufacturers, who must commit to building liquid-capable servers at scale, and colocation providers, who must themselves commit to supporting liquid cooling from a practical and mechanical perspective.
To democratise liquid cooling and tackle e-waste in the process, industry leaders, including Equinix, have joined the Open19 Foundation to reduce equipment redundancy by standardising the design of key infrastructure elements, including services, storage and networking. For example, the open-source hardware project is supporting the development of a new ‘plug-and-play’ coupler for liquid cooling systems. Furthermore, in collaboration with the Open 19 project, companies are developing industry standard servers that do not contain surplus components and are more durable with a lifespan of 10 to 12 years, compared to today’s average of three to five years.
Data centres not fitted with liquid cooling technologies can improve efficiency through optimised airflow management. Rather than allowing hot air and cool air to flow throughout the facility at random, physical barriers are deployed to restrict cool air to supply aisles and hot air to exhaust aisles that swiftly remove waste heat. The heat can then be captured and redeployed as a source of low-carbon heating for nearby homes and businesses.
To further reduce its environmental impact, the industry is also looking at ways to meet water usage effectiveness (WUE). One way to do this is by switching to fuel cells that require less water and are up to 45% cleaner, and by using recycled water by harvesting rainwater and non-drinkable water. These methods will help the industry meet the expected WUE of 0.4 L/kWh by 2025 for data centres at full capacity.
Finally, global data centre providers have the advantage of operational scale, which delivers energy efficiencies not only to their facilities but also to their customers. Centralisation saves energy simply because it is more efficient to have all storage and computing power concentrated in a few places around the world, rather than in the server rooms across thousands of individual businesses.
While positive progress is being made across the industry to reach net zero by 2030, there is still more to be done. The challenges facing the data centre industry are too complex to be addressed by organisations working in isolation. It will take a concerted effort by industry leaders, governments, policymakers, technologists and innovators working collaboratively to meet this ambitious target by the end of the decade.
