Why calculate a website's carbon footprint?

🌎 Understanding your environmental impact

Data centers, the backbone of web hosting, are real energy consumers, often powered by non-renewable sources. Their high demand for capacity makes them a major factor in reducing the digital carbon footprint.

This high energy expenditure comes from several sources:

• Data centers account for 1.5% of global energy consumption. But theInternational Energy Agency (IEA ) warns that this share could rise to 10% by 2030 if no significant action is taken.

• Data transfer networks are powered by energy-hungry infrastructures

• User terminals, such as smartphones and computers, also use electricity.

This is an alarming finding , given that terminal production alone accounts for between 65% and 90% of the carbon footprint of the digital sector in France.

These are the findings of a joint report byArcep andADEME, commissioned by the French Ministry of Ecological Transition and the Ministry of the Economy, Finance and Economic Recovery. This data underlines the urgency of taking action right from the production phase to reduce the environmental impact of digital technology.

✅Meeting stakeholder expectations

In a context of growing environmental awareness, customers and partners are increasingly sensitive to the digital impact of companies, and are demanding concrete action to reduce their environmental impact. Indeed, "9 out of 10 French consumers expect companies to respond to social and environmental issues", according to the French Senate.

What's more, committing to a CSR approach by carrying out a website carbon footprint is an opportunity for a company to demonstrate its environmental commitment, while meeting stakeholder requirements and gaining credibility with an aware audience.

A joint study by Razorfish, the digital agency of Publicis, and the GreenIT collective has examined the ecological impact of the 90 most emblematic websites in the French economy, including those of the CAC 40 (major e-commerce platforms, media and public services).

The results are unequivocal and reveal an alarming impact:

🔺Every year, French websites emit 7 million kilos of CO2 equivalent, or as much as 1007 world tours [1].

🔺 These digital portals consume 106 million liters of water, the average consumption of a French person for... 1983 years[2].

[1] Based on an average distance travelled of 45 million km for 7.6 million keqCO₂ discharged.

[2] Based on an average of 146 liters of water consumed per day according to the volume of drinking water consumed per inhabitant per day in 2016 published by Eau France in 2020.

📈 Optimizing performance

This explosion in the weight of digital interfaces, multiplied by 155 between 1995 and 2022 according to EcoIndex, illustrates the urgent need to rethink site design and management.

In this context, website optimization becomes an essential lever, offering benefits not only for the environment, but also for companies' economic performance:

• Lower storage costs thanks to lower data volumes.

• Improved user experience: a lighter interface loads faster, reducing the bounce rate. The average loading time for a mobile page is 22 seconds. According to a Google marketing study, "1 in 2 visits to a mobile site is abandoned after 3 seconds".

Correlation between digital interface transfer time and bounce rate

• Better SEO performance: Search engines favor fast, well-optimized sites, increasing their visibility and attractiveness.
• Reduced carbon footprint: By reducing the volume of your digital interface, you limit the use of non-renewable energy, which is linked to computer systems and information transfer, thus contributing to a more sustainable digital environment.

What are the main categories of website emissions?

♨️ Hosting and servers

Data centers are a major source of carbon emissions. In 2022, the worldwide consumption of these hosts consumed 460 terawatt-hours (TWh) of electricity, according to Franceinfo.

The key factors are :

• Energy source: Data centers using fossil fuels emit far more than those using renewable resources.
• Data volume: A large site (number of pages, large files) is particularly energy-intensive to store and serve.
• Distance from computer systems: transfers over long distances consume more energy.

💡 Structure and content

The way a website is designed has a direct influence on its carbon emissions.

• Large files: Uncompressed images and autoplay videos weigh down digital interfaces.
• Non-optimized code: Inefficient code places greater demands on IT systems, slows down the site and increases its carbon footprint.
• Unnecessary plug-ins: Non-essential functionalities weigh down the site.

📲 Traffic and usage

A website's energy consumption is directly linked to its traffic and the way it is used by visitors. Each visitor triggers a chain of actions (displaying a page, transferring information) that consumes energy. The longer and more numerous the sessions, the more CO₂ emissions the site generates.

• Number of visits and session duration: Increasing the frequency and duration of sessions significantly increases energy consumption.
• User location: Users located far from IT systems increase the need for data transfer.