The illusion of the web’s immateriality

The Internet gives the impression of being immaterial. You click, the page loads, and nothing seems to burn. Yet behind every page load, servers are running 24/7. Data centers consume constant energy for cooling, creating an invisible bill.

According to Arcep and ADEME, digital technology now generates 3 to 4% of global greenhouse gas emissions. The Shift Project states that this sector pollutes more than civil aviation, which accounts for 2 to 3%. Unlike factories, this pollution remains invisible. As a result, users rarely question it.

What is a “heavy” website?

A “heavy” website often looks perfectly fine visually. In reality, it accumulates uncompressed images, unnecessary JavaScript scripts, autoplay videos, and forgotten plugins.

According to the HTTP Archive, the median weight of a desktop page reached 2.6 MB at the end of 2024. In 1995, a web page weighed only 14 KB. Its weight has therefore increased by a factor of 180 in barely 30 years. With each visit, the server sends this data and the browser processes it. This process consumes electricity both on the hosting provider’s side and on the user’s device.

The energy consumption chain

Three key links share the energy consumption of a website:

The data center that hosts the files.
The network that transports the data.
The user’s device that displays the page.

A poorly optimized website puts pressure on each of these links for longer. Multiplied by thousands of monthly visits, the environmental impact becomes very real.

Let’s imagine a website that loads 3 MB on every visit. With 10,000 visitors per month, the servers transfer 30 GB of data. Reducing this weight by half directly limits these transfers and the associated energy consumption.

Why digital sobriety is not the norm

Modern frameworks such as React, Next.js, or Nuxt impose a base amount of code that cannot be fully compressed. A simple “Hello World” in React already weighs 40 KB when minified. In addition, ready-made themes often offer twenty features for only three real needs. Bandwidth is so cheap that designers tend to treat it as unlimited.

The Shift Project predicts that emissions from the digital sector could double if nothing changes. They would unfortunately reach 7 to 8% of total global emissions.

The web is therefore becoming increasingly resource-hungry. Today, performance and sobriety come from a deliberate choice, not from a default configuration. Meanwhile, servers keep running.

The web facing the ecological challenge

Digital technology now represents around 4 to 5% of global greenhouse gas emissions, a figure that continues to rise according to ADEME. Data centers, networks, and devices consume a huge amount of energy.

Faced with this reality, the web is adapting. The concept of Green IT is developing: code optimization, green hosting, and website eco-design. Companies such as Google and Microsoft are committing to carbon neutrality and the use of 100% renewable energy.

The “Numérique Responsable” label and tools such as GreenFrame now make it possible to measure the carbon footprint of a website in concrete terms.

The web can become an ecological lever, provided that its stakeholders make it a priority.