logo terra-num

consulting firm specializing in the sustainable digital transition of corporations, businesses, and public institutions.

For years now, the digital world has been a major component of both our personal and professional lives. The economic, environmental, and social impacts of these technologies are equally positive and negative. Today, as businesses slowly begin their digital transition, the climate crisis is only getting worse. Now, the goal of sustainable development is to bring together both issues, for the sake of our planet  🌍

Find out more

Our mission

Le numérique responsable, c'est quoi ?

c'est une démarche qui vise à réduire l'empreinte écologique, économique & sociale des TIC. 



green IT and its main challenges

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awareness among citizens and the workforce



corporate & local stakeholders

Our values

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of the humankind & out planet

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to providing support in a totally positive way

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approach because together we go even further

Get on board with us for a
more responsible digital world!


homme qui tient la planète


• we assess your organization
• we provide a strategic vision & a roadmap
• coaching on digital responsibility 

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• conception of the roadmap
• raising awareness and training
• implementation
• monitoring (actions & follow-up)
• certification (preparing for the Green IT certification)  



We provide training programs designed to increase awareness among employees and citizens, including students and even children, about the environmental, economic and social issues related to digital technology... and to educate them on the best practices to implement!

Our team of experts

olivier langlet

Olivier Langlet

CEO & green IT expert

As a digital entrepreneur for the past 20 years, an ambassador of the Reboot Ecosystem project and member of the scientific committee at the INR (Institut du Numérique Responsible – French Think Tank on Green IT matters) - Olivier has surrounded himself with a strong team of experts. He has succeeded in developing an ecosystem dedicated to digital inclusion, green IT and the promotion of citizen awareness on environmental, economic and social issues.

olivier langlet

Guillaume Gallon

Digital architect & Green IT specialist

From developer to project manager, IS architect, innovation director & Green IT coach, Guillaume has a well-rounded and solid professional background. He is an expert in business matters, supply, management, IS architecture design, and digital transformation; and all of this within a sustainable development framework.

olivier langlet

Marie Horville

Consultant in sustainable communication & marketing

With a background in communication and marketing and a keen interest in environmental issues, Marie decided to combine both worlds. Her goals? Make IT accessible to everyone & help businesses incorporate the notions of Corporate Digital Responsibility into their global strategy. She is also committed to promoting responsible, coherent and transparent communication.

Green IT & Digital Responsibility

This initiative focuses on reducing the environmental, financial and social footprint of ICTs.

For over a decade now the challenges arising from the environmental impact of the digital world have been considered and addressed by different organizations, promoting the development of GreenIT and the sustainable design of digital tools.

Launched in June 2019, the NR (Numérique Responsable – Digital Sustainable) certification is the first French certification providing an operational framework for this approach, based on 3 key principles:
People - ensuring that people are at the center of the whole process
Planet - ensuring that the environment is respected and preserved
Profit - promoting economic attractiveness 

Why Terra-Num ?

We want to support and help both corporate and local authorities to achieve their sustainable development goals through a sustainable digital transition. Because we strongly believe that our planet and our digital world are made to exist harmoniously, in a sustainable and ethical way. And, in order to succeed, we need to work together  💚🌎

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Facts & Figures

The digital world generates 3.8% of greenhouse gas emissions.
The environmental footprint of the digital industry represents 2 to 3 times that of France.
Equipment production is responsible for 70% of pollution and the remaining 30% is due to the final use of the equipment. 

If you want to know more about the figures and the environmental impact of the digital world, follow us on our social networks or visit the website of the Institut du Numérique Responsible

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Everyday actions to adopt...

Unplug and turn off my devices when I'm not using them!

(this allows me to save energy, money & above all I keep my devices for a longer time)

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Everyday actions to adopt...

Gather information, learn and educate my friends and family!

(and if I have any questions, I can always get in touch with the Terra-Num team for a coffee and a chat)

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Everyday actions to adopt... 

I don't change my smartphone or my computer if they still work!

(and if they don't work anymore, I don't throw them away. Instead, I choose to recycle them and buy a second-hand device)

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Our team supports your sustainable digital transition projects.