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CERN releases its second Environment Report setting out concrete actions to reduce its environmental footprint

The report covers the years 2019-2020 when the accelerator complex was in its second long shutdown, an opportunity for CERN to improve its environmental footprint on several levels

HL-LHC P1 Concrete coating
Having the HL-LHC civil engineering overseen by an environmental engineer was one of the contractual conditions for these essential works for CERN’s future flagship facility. (Image: CERN)

CERN released its second public Environment Report today. The report covers the years 2019-2020 when the accelerator complex was in its second long shutdown. The Organization took the opportunity of this maintenance and upgrade period to improve its environmental footprint on several levels: for example, by limiting CERN’s direct greenhouse gas emissions and by working on local heat recovery projects. In addition, a major objective of the long shutdown was to prepare the ground for the high-luminosity upgrade of the Large Hadron Collider (HL-LHC), which is being done with environmental considerations firmly in mind.

To ensure transparency and to demonstrate its leadership in environmental management for research organisations, the Laboratory made a commitment in 2019 to communicate on its environmental footprint every two years and in alignment with the internationally recognised GRI Sustainability Reporting Standards.

“The production of CERN’s first public Environment Report in 2020 enabled us to establish reporting frameworks and set concrete goals. This second report is about turning words into action,” declares CERN Director-General, Fabiola Gianotti.

To limit CERN’s direct greenhouse gas emissions, mostly related to the use of various fluorinated gases (F-gases), the experiments launched a leak repair campaign to decrease F-gas emissions. The second long shutdown also marked the first step towards replacing F-gases with carbon dioxide (CO2) in detector cooling systems. CO2 has a substantially lower global warming potential than F-gases. This effort contributes to last year’s commitment to reduce greenhouse gases by 28% by the end of 2024.

CERN is also working on various heat recovery projects. In 2019, the Organization signed an agreement with the local French authorities regarding the collection of heat from its facilities at Point 8 of the Large Hadron Collider to provide heating for a residential area in neighbouring Ferney-Voltaire. Houses will be heated with reduced CO2 emissions and at a lower cost. The quantity of heat delivered will be progressive over 8-10 years, ultimately reaching 20 GWh/year. A plan to test the functionality of the system is scheduled for the end of 2022. CERN is continuing to explore heat recovery on the Meyrin and Prévessin sites.

The Environment Report also describes the energy efficiency improvements implemented at the HL-LHC, in particular its ability to gather more data per unit of energy used. Over the 20-year life-span of the upgraded machine, energy efficiency will eventually rise to a factor of ten higher than when CERN’s flagship facility was originally switched on.

In addition to direct greenhouse gas emissions (scope 1) and indirect greenhouse gas emissions related to electricity consumption (scope 2), this year’s report presents for the first time data related to other indirect emissions (scope 3), including business travel, personnel commutes and catering. A procedure for evaluating procurement-related emissions and a project for greening CERN’s procurement are under preparation and will be covered in a future report. “CERN is reporting on its scope 3 emissions for the first time, marking an important step in understanding and controlling the environmental impact beyond CERN’s walls, upstream and downstream in our supply chain,” says Benoît Delille, head of the Occupational Health and Safety and Environmental protection unit at CERN.

Link to read Environment Report: https://hse.cern/environment-report-2019-2020