How Nantes Metropolis is keeping its digital footprint under control — even as infrastructure and applications expand
In 2021, Nantes Métropole became one of the first French local authorities to launch a public policy dedicated to sustainable IT. With over 677,880 residents, the city is directly affected by the REEN* law (*Reducing the Environmental Footprint of Digital Services), which since 2025 requires all large municipalities to publish a responsible digital strategy.
Rather than producing a one-off assessment, the city sought a long-term framework to monitor its footprint, assess the impact of existing actions, and embed environmental performance into day-to-day decision-making.
“There’s a growing urgency to understand and manage the environmental impact of digital technology.”
About
Nantes Métropole is one of France’s leading metropolitan authorities that coordinates public services, innovation and climate action across 24 municipalities and over 660,000 residents.
https://metropole.nantes.fr/
Challenge
More than just a measurement exercise, Nantes Métropole aimed to turn carbon footprint data into a practical tool for steering its IT strategy — aligned with existing initiatives and regulatory requirements. The key priorities were:
Establishing a reliable baseline to define a long-term emissions reduction trajectory
Including digital services — not just equipment — in the calculation perimeter
Valuing the progress made since 2021
Connecting the approach to other strategic frameworks (climate, procurement, quality)
Building a replicable model for use by other municipalities across the region
Solution
After comparing multiple solutions, Nantes Métropole selected Aguaro for its ability to structure a broad, dynamic, and interoperable measurement model. The platform was deployed in standalone mode and integrated with existing tools, including Ivanti for asset management.
Over a four-month period, teams defined the scope, structured the data, and produced an initial carbon footprint. The perimeter now includes equipment, usage, and infrastructure — with plans to extend to business applications. The clarity of the results helped drive internal ownership and create synergies with other initiatives.
Results
Carbon footprint stabilized despite a 26% increase in staff equipped and a 33% increase in the application portfolio
Responsible digital strategy now integrated into the Climate Air Energy Plan and sustainable procurement framework
Active support for the IT Department’s quality strategy, benefiting over 80 business units
Strong engagement from internal teams thanks to a clear visualization of environmental impacts
Shared platform being rolled out across member municipalities to build a common, reusable model
By combining structured data with shared governance, Nantes Métropole is turning carbon measurement into a strategic lever — helping shape a digital future that’s more efficient, more aligned, and truly anchored in the ambitions of the territory.
