Our website uses less energy:
here’s why

Our website consumes less!

This website was designed to limit CO2 emissions, reduced by 64% compared to our previous website. We are making a concrete commitment to carbon neutrality!

Sylvie Jéhanno,

Chairwoman & CEO of Dalkia

When we use the internet, we are not really aware of the energy consumed by what we read, watch or listen to, – despite the fact that the digital world accounts for 4% of global greenhouse gases – more than air travel! We decided to design our site sustainably, with the greatest possible accessibility, to take collective action and perhaps inspire others to do the same

A less energy-intensive site

We have chosen to use sustainable web design to reduce the amount of data transferred between the site and the servers, limiting energy and resource use. There are six pillars to our approach.

More lightweight pages

We have limited the number of images, videos or PDFs embedded into each page, and carried out a specific compression of each of the images as well as a single color processing with a fairly low number of pixels.

Record loading times

Reduced page sizes and efficient code have enabled us to reduce the amount of server requests, which speeds up loading times (before this "diet", this could go up to 9 seconds per page).

A less energy-consuming architecture

We have coded the site to maximise efficiency and limit the load on the servers in order to consume less energy.

A forced diet

We have limited the number of pages on the site (compared to the previous website, we divided by 4 the number of pages - excluding job offers), with a simplified browsing experience for users.

Unsystematic videos

We have gotten rid of autoplay videos. Users only watch the videos they want to see.

Responsible web hosting

100% of the energy used by our hosting service comes from renewable sources. We have limited the number of servers (two, down from seven on our old site) and the amount of data backed up daily. Our site is static from 10pm to 8am and on weekends, eliminating some server requests during those hours and days.

Reduced size and data transfers

The internet accounts for a sizeable percentage of energy use and, as the saying goes, a picture is worth a thousand words! We have sought to build the most lightweight website possible to reduce the size in bits and limit the energy used by servers to store the data and by users to view it. That is why the photos appear in a single tone with a relatively low number of pixels, and why you won’t find many videos. We have also chosen technical development and coding methods that limit the amount of data transferred between the site and the servers.

Improved accessibility

We haven’t made any compromises when it comes to content accessibility for people with disabilities. It’s something we care a lot about, which is why all users are able to activate the site’s key functionalities:

EcoIndex ratings: how they work

The EcoIndex rating measures the pages’ environmental performance from A to G, the same scale as for household appliances. The rating for each page (or URL) is based on three technical parameters: 

This site contains

99% pages with an A or B rating1% pages with a C rating

N.B.: The EcoIndex ratings that you will see on our website were obtained following an audit carried out in July 2021. These ratings may vary depending on your browser and your settings (activation of ad blocker, etc.).

Complexity of composition

(for the tech savvy: the number of elements in the Document Object Model, or DOM), which gives an idea of the energy consumed by the user’s browser to display the page

Amount of data transferred,

in Kb, which reflects the energy needed to transfer the content from the server to the browser

Number of Hypertext Transfer Protocol (HTTP)

requests that the browser sends to the server.

This site contains

99% pages with an A or B rating1% pages with a C rating

N.B.: The EcoIndex ratings that you will see on our website were obtained following an audit carried out in July 2021. These ratings may vary depending on your browser and your settings (activation of ad blocker, etc.).

A concrete contribution to carbon neutrality

To limit our impact on the climate, we have significantly reduced the volume of carbon emissions compared to our previous website (-64%), and we have financed a forestry project which has been labeled by the Ministry of Ecological Transition via the Low-Carbon Label.


This carbon offset project will store 300T of CO2 equivalent CO2 eq over 30 years thanks to the planting of more than 1,400 trees in Seine-Maritime, which corresponds to the annual residual emissions of our external digital platforms.

By redesigning our site in 2021, we have improved its overall EcoIndex rating from E to B. Its carbon footprint, now stands at 1,48 g CO2-eq (per visit).

Reference points for CO2 emissions

1 kg CO2-eq equals*:

A few measurements of the impact of everyday activities*:

* Source: various studies by Ademe, the French agency for ecological transition (estimations may vary by year and country).

Dalkia and the energy transition

Through our work on behalf of our clients, we reduced CO2 emissions by 4 million tonnes in 2021, the equivalent of taking more than two million vehicles off the road. Dalkia has been committed to the energy transition ever since the company was founded, in 1937. We remain committed to this day, through business activities that focus on three key goals:

King Fahed university Hospital

King Fahd University Hospital in Khobar (KFUH) is undergoing a comprehensive project to improve energy efficiency and modernize its facilities. The project implementation includes 15 Energy Saving Measures (ESMs) which address key components of the facility in order to secure their performance and guarantee savings. The project is developed under a partnership with Tarshid.

Kindgom Tower, KSA

Riyadh's most iconic tower, built over 20 years ago, covers an extensive area of 300,000 square meters. This multifaceted structure includes a Four Seasons hotel, a conference center, a shopping mall, offices, residences, and a large parking area. Our proposed solution focuses on making the tower's day-to-day operations and maintenance more effective, particularly for its mechanical, electrical, and plumbing systems. We're also implementing energy-efficient practices and exploring sustainable cooling solutions through cooling networks for the tower.

Abu Dhabi airport Terminal A, UAE, UAE

Dalkia manages Abu Dhabi Airport's largest chiller plant at the Midfield Terminal Complex, with a total capacity of 54,000 RT.

Built in 2016, the emphasis is on achieving full terminal functionality by 2023, with a focus on efficient chiller plant management and energy-efficient operations, including rigorous preventive maintenance aligned with airport protocols.

UAE University, UAE

Dalkia successfully implemented a comprehensive Energy Performance Contract for UAE University, achieving significant savings in Phase 1. Dalkia has been awarded Phase 2 by ADES, expanding to more campus sites and is now in implementation phase. Simultaneously, negotiations for Phase 3 are ongoing.

Complementing these efforts, Dalkia launched an Energy Awareness Campaign at the university, promoting sustainability and engaging stakeholders in energy-conscious practices.