Researchers propose innovations for datacenter cooling

It is well known that tropical climates have characteristics that can have a serious impact on datacenter operations. In these climatic conditions, these environments tend to consume more energy for cooling to cope with higher ambient temperatures. Heatwaves can also lead to more equipment failures, affecting the performance and reliability of servers and other hardware components. As if that weren’t enough, excessive levels of humidity, another characteristic of tropical climates, generate more condensation and, consequently, more potential damage to equipment.

Now, what researchers in Singapore, a country located in Southeast Asia where a hot and humid climate prevails throughout the year, want to know is how to develop sustainable cooling technologies for datacenters located in the tropics. To this end, a group has opened a test facility on the campus of the National University of Singapore (NUS), the first of its kind in the world. On average, around 40% of datacenter energy consumption goes on cooling and ventilation systems.

Named the Sustainable Tropical Data Centre Testbed (STDCT), the centre is designed as a living laboratory in a 770 m2 footprint for scientists to experiment with and validate cooling innovations in a realistic tropical environment. It is jointly managed by NUS and Nanyang Technological University (NTU Singapore) and involves partners from academia and industry, with the aim of accelerating the adoption of refrigeration solutions adapted to the tropical climate and defining sustainability standards suitable for operations in the tropics.

“In the long term, STDCT will also be a platform for other universities and companies to validate new solutions. This allows the industry to have a wider adoption of best practices for sustainable datacenters in the tropics,” said Alvin Tan, Singapore’s Minister for Trade and Industry.

STDCT will provide infrastructure support for a comprehensive programme starting in June 2021. Twenty industry collaborators have contributed cutting-edge technologies and are actively engaged in technology co-development, including Dell, Eaton, Intel, Keppel, Meta, Schneider Electric and Shell. By November 2023, the SDCT had already attracted more than $30 million in investment for five research projects led by NUS and NTU scientists.

“This new test facility supports five research projects under the STDCT programme. These projects involve holistic assessments to identify opportunities for raising the recommended temperature of conventional datacenters, identifying sweet spots for sustainable cooling solutions and integrating these technologies into the environment,” explains Associate Professor Lee Poh Seng, director of the STDCT programme.

Three projects will focus on developing advanced cooling technologies. One team will design a heatsink coupled with an immersion cooling system. Another team will devote itself to a hybrid cooling system directly on the chips with a high-performance hybrid heatsink design with two liquid and air cooling. The third team will validate the potential of a new cooling solution using a high-performance hygroscopic material.

In parallel, other scientists will lead a project aimed at establishing optimal temperature and humidity settings for cooling datacenters in the tropics, and a second initiative will develop digital twins for new cooling technologies that will enable real-time modelling and performance prediction, as well as optimisation of energy efficiency and sustainability measures based on Artificial Intelligence (AI).

With these projects, the STDCT programme aims to demonstrate the following results in a tropical scenario by mid-2024:

• Reduce energy consumption by up to 40 per cent;
• Reduction in water use by 30 to 40 per cent;
• Reduction of carbon dioxide emissions by around 40% to less than 0.54 million tonnes per year;
• Power Usage Effectiveness (PUE) of less than 1.2 for a combination of air and liquid cooling, below the Singapore government’s current requirement of 1.3 and the global average of 1.5 in 2022).

In June 2023, Singapore’s IMDA (Infcomm Media Development Authority), which is responsible for developing and regulating the communications, information and media sectors, announced a sustainability standard for new datacenters to allow operations at higher temperatures while optimising energy efficiency.

In the fourth quarter of 2024, the STDCT expects to publish a white paper with recommendations on optimal datacenter design and operations.

In terms of training, the STDCT will establish partnerships to offer training opportunities for students and industry professionals as early as 2024. As a first step in this field, STDCT has already offered two scholarships with the support of partners to train local talent in some areas, such as AI-based digital twins and advanced liquid cooling systems.