Does Deleting Emails Really Help Save the Planet?

In our increasingly digital world, emails have become an essential part of everyday communication. Yet, behind each message is a hidden energy cost that adds to an often unnoticed environmental impact. As email volumes continue to rise, so does the demand on energy-intensive data centers that support them. So, if these digital piles cost energy to keep, will deleting emails make a difference for the environment?

Hidden Energy of Emails

Every email sent, received, or stored requires energy to process and save on remote servers. These servers are housed in massive data centers and run continuously, consuming significant electricity for both computing and cooling. In 2024, global data centers used about 415 terawatt-hours (TWh) of electricity, accounting for roughly 1.5% of the world’s total electricity consumption.

The massive volume of email traffic significantly increases its hidden energy cost. About 361 billion emails are sent and received each day globally in 2024, and this number is expected to reach 408.2 billion by 2027 as connectivity increases. With each message requiring storage and processing, the cumulative demand on these energy-intensive data centers grows rapidly.

Environmental Cost of Email

Globally, digital activities already make up about 4% of total greenhouse gas emissions and are projected to rise sharply. What about the amount that comes from emails?

The environmental impact of emails can be measured in the digital carbon footprint, known as CO₂e (carbon dioxide equivalent). Research by sustainability expert Mike Berners-Lee shows that the environmental cost of an email depends on how it is created and delivered. A basic email sent between phones may produce as little as 0.2 grams of CO₂e, while spam caught by filters generates 0.03 grams. On the other hand, emails that include large attachments or require more time to compose, such as long and detailed messages, can produce up to 50 grams of CO₂e.

In a year, the average person’s email usage can produce between 3 to 40 kilograms of CO₂e,  which is the same as driving a small petrol car for 16 to 206 km. Although each email may have a relatively small carbon footprint, with billions sent daily, the impact adds up fast.

Deleting Emails and Other Sustainable Digital Habits

Deleting emails might seem insignificant, but it can play a role in reducing the digital carbon footprint. For instance, deleting 1,000 emails can save about 5 grams of CO₂e. The individual impact may be small, but if billions of people do it, the collective energy saving could be meaningful.

However, most of the carbon footprint linked to emails does not come from the messages themselves, but from the devices we use to send and read them. Manufacturing electronics is carbon-intensive, especially when powered by non-renewable energy. Furthermore, electronic waste is a mounting issue that needs careful management. Therefore, a more impactful step than simply deleting emails is to extend the life of the devices, avoid unnecessary upgrades, and choose energy-efficient tech.

In the grand scheme of things, emails in our inboxes are not the biggest emission problem on the planet, but it is an easy one to tackle. Deleting unnecessary messages, unsubscribing from unwanted emails, emptying spam folders, and managing storage are small steps that can support broader efforts to reduce digital waste. More importantly, being more mindful about the environmental cost of our emails also means adopting a more sustainable lifestyle overall.

Editor: Nazalea Kusuma

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