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Environmental awareness: how CERN supports and encourages alternative forms of mobility

A step-by-step approach to environmentally responsible commuting and duty travel

Bike station at CERN
A bike station at CERN - cycling makes up about 15% of all commutes to and from CERN (Image: CERN)

With a site spanning some 600 hectares across two Host States, commuting and intra- and inter-site mobility pose a real challenge for CERN. With road traffic accounting for 19% of Europe’s total greenhouse gas (GHG) emissions, reducing the use of road transportation in commuting and duty travel represents a clear lever for CERN to impact its indirect GHG emissions.

In 2015, a survey by the Canton of Geneva focusing on international organisations in the region revealed that 17% of CERN commutes were made by soft mobility (cycling and walking), which is higher than the French average and on a par with the Swiss average. This was confirmed by a mobility survey carried out at CERN in 2018. Around 70% of CERN personnel live in France and most commute by car owing in part to the lack of public transport.

Commuting averages for soft mobility and public transport to and from CERN, compared to Switzerland and France. (Image: Mobilidée 2015, Swiss Federal Statistical Office 2019, INSEE 2017)

CERN’s goal for 2025 is to keep individual motorised vehicle commuting constant. In close collaboration with the local authorities, CERN has implemented several initiatives to encourage soft mobility both to/from and at work. These include the shuttle service and a fleet of bicycles available free of charge to members of the personnel. In 2021, CERN launched a pilot scheme for free rental of e-bikes and e-scooters on its two main sites, and has also increased its cycling routes (a map showing all the cycling routes around CERN can be found here).

A topic that comes up with increasing frequency concerns electric cars. As a move in this direction for CERN’s own vehicle fleet implies major investments in the infrastructure, the Organization is implementing a gradual approach by evaluating a reduction of the current professional car fleet and the possibility to use electric cars on site.

All mobility projects and new approaches are closely followed up and regularly reviewed by SCE in collaboration with other departments. Since 2016, a working group on mobility has been continually investigating practices at CERN and proposing ways to optimise its mobility infrastructure.

Duty travel is also the subject of a dedicated working group, with a view to updating the CERN-wide guidelines on the matter and considering how to empower and encourage CERN personnel to make climate-conscious decisions when planning such travel.

In addition, the Organization takes part in wider exchanges on mobility with the Canton of Geneva and other international organisations in the region.

Finally, CERN relies on collaboration with its Host States to optimise commuting to and between the sites. In this context, the Ain Department is currently evaluating a project with the aim of developing alternative modes of transport to individual cars and to simplify the routes for pedestrians and cyclists around the Porte de France near CERN’s Gate E.

As we return to regular on-site work in COVID-19 Level 1 – Green, now is a good time for us all to reflect on our mobility habits and how we can effectively contribute to reducing GHG emissions in our own way. Car sharing, taking the bus or cycling, even just once a week, can make a significant difference. Biking to work is not only good for the environment: it has tangible health benefits too. And let us all remember to respect each other whatever our mode of transport, acting in a safe manner towards all road users, whether it be on foot, two wheels or four.


This article is part of the series “CERN’s Year of Environmental Awareness”.