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Building work for CERN’s new data centre in Prévessin begins

On Friday, 22 April, a ceremony was held to mark the beginning of construction of CERN’s new energy-efficient data centre


Cérémonie de pose de la première pierre du Centre de calcul du site de Prévessin, Vendredi 22 avril 2022
Representatives of CERN and of the EQUANS France-Léon Grosse-Agapé consortium involved in the first-stone ceremony (Image: CERN)

On Friday, 22 April, a special ceremony was held to mark the beginning of construction of CERN’s new data centre. The CERN Data Centre in Prévessin will come online during the final quarter of 2023. This new, energy-efficient facility will play a vital role in meeting the computing needs generated by the ambitious upgrade programme for the Large Hadron Collider (LHC).

When the High-Luminosity LHC (HL-LHC) comes online in 2029, the total computing capacity required by the experiments is expected to be ten times greater than today. Some of this shortfall will be filled by harnessing new, cutting-edge technologies and techniques: today, projects are examining how code can be modernised, how to capitalise fully on heterogeneous computing architectures, and how to benefit from the use of machine- and deep-learning approaches. Nevertheless, a significant increase in computing resources will be required.

“Computing is central to CERN’s mission,” says Charlotte Warakaulle, CERN Director for International Relations, who participated in the first-stone ceremony for the new data centre. “It turns data into knowledge, helping physicists unlock the secrets of the universe.”

The CERN Data Centre in Prévessin will provide computing resources up to a total electrical power requirement of 12 megawatts. These resources will be delivered in three phases. Each phase corresponds to one of the three floors of the new data centre, with the first phase set to run from 2023 to 2025. It will see computing resources requiring up to 4 megawatts of electrical power installed; this is approximately the same as the power of the current CERN Data Centre in Meyrin for computing (excluding cooling).

The CERN Data Centre in Meyrin will continue to run in parallel, with a particular focus on data storage. Together, the two data centres will form the heart of the Worldwide LHC Computing Grid (WLCG), the global computing network used to analyse and store data from the LHC experiments. Today, the WLCG consists of 170 computer centres in 42 countries that formally pledge computing resources. Together with tens of additional computer centres that contribute on other terms, they have been able to provide up to 1.4 million computer cores and 1.5 exabytes of storage.

Energy efficiency is at the core of the new data centre’s design; CERN's Procurement Service paid special attention to including sustainable solutions for the new building. CERN aims for the new data centre to have a power usage effectiveness (PUE – an indicator used for measuring the energy efficiency of a data centre) of around 1.1. To put this in context, the global average PUE for large data centres is around 1.5, with new data centres typically achieving a PUE between 1.2 and 1.4 (the closer to 1.0, the better the PUE score). The PUE of the CERN Data Centre in Meyrin is about 1.5.

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An artist’s impression of the CERN Data Centre in Prévessin. The facility will consist of three floors, to be progressively filled with computing equipment over the first ten years of operation. (Credit: + IMGS – Rocco Valantines)

The CERN Data Centre in Prévessin will make use of the latest cooling technologies and will recuperate heat energy for warming other buildings on site. During the data centre’s first phase of operation, the majority of the rejected heat will be recovered. Projects for using this are now under consideration, with the target of bringing them online during this first phase.

“We’re proud that our new data centre will achieve the highest levels of energy efficiency,” says Enrica Porcari, Head of the CERN IT department. “This helps us to keep costs down and fulfil our commitment to protecting the environment.”

Enrica Porcari and Charlotte Warakaulle were joined at the first-stone ceremony by Pippa Wells, CERN Deputy Director for Research and Computing, and Wayne Salter, leader of the project behind this new data centre. They were also joined by representatives of the companies that will be responsible for building the new data centre and operating it for the first ten years. Together, the group placed a time capsule into the building, containing a microprocessor, the signed contract for the new data centre and a photo of members of the IT department in 2022.