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In honor of Earth Day 2023, which is celebrated on April 22 this year, here are a few tips and tricks you can apply to your internet habits to celebrate Earth Day every day, including understanding and reducing the carbon footprint of our emails.

In today's world, the internet has become a lifeline for many of us, allowing us to send emails and share pictures and videos all at the touch of a button. 

333.2 billion emails are sent per day. That means that more than 3.5 million emails are sent per second. And the number is still growing.

Yet, while the internet has fundamentally transformed how we go about our daily lives, our online habits also surprisingly impact the environment. 

Why are emails so bad for the environment?

Every online activity undertaken results in a few grams of carbon dioxide being emitted due to the energy needed to run your devices and power the wireless networks you access. In parallel, the data centers and vast services required to support the internet are also highly energy intensive.

It's an important fact: sending an email causes CO2 emission.   

Have you ever considered the carbon footprint of your mail messages?

According to Berners Lee's book, The Carbon Footprint of Everything, a normal email has a footprint that ranges between 0.03g and 26g of CO2 emissions

This can rise to 50g with the addition of a large attachment. When you sent that cat video to your family and friends, it was funny, but did you realize that this large attachment also released around 50g of CO2 in the atmosphere?

That is the same amount as using five plastic carrier bags...

Luckily, devices and data centers are becoming more efficient. 

But the number of emails is going up, and the issue of internet pollution is expected to continue growing rapidly as digital transformation of all aspects of our lives takes place. 

Spam emails are a serious issue for the planet.

According to Statista, in 2022, nearly 49 per cent of all emails worldwide were identified as spam, up from 46 per cent in 2021. This explains why 80% of emails are never opened. Mailboxes are saturated and polluted with messages that do not interest you.

Moreover, storage also emits CO2, more precisely 10g for one year of storage on average for an email.  

This is largely because the infrastructure behind every message, which includes the electricity usage and the energy to store and transmit emails through data centers, is huge, as the data centers need to be air-conditioned and kept very cool to avoid overheating.

An estimated 88.9 billion spam emails are sent per day.
While remaining a big part of the email traffic, since 2011, the share of spam emails has decreased significantly. 
In 2022, the highest volume of spam emails was registered in February, approximately 53 per cent of email traffic worldwide.

Source: Statista 



How to cut down your email pollution

But if these mails were cleaned, CO2 emissions would be significantly reduced. Starting by deleting old emails and thinking about unsubscribing from intrusive newsletters are small choices with a big environmental impact.

A digital cleanup is a free alternative that will impact your carbon footprint.

While using email means we are less reliant on paper, which is good for the environment, there are a few tips and tricks to manage your emails more efficiently and reduce your email pollution. We've listed a few below.

  • Write concisely and keep messages as brief as possible.
  • Hyperlink files or information held online rather than adding an attachment.
  • Only subscribe to the news services that you want.
  •  Avoid sending unnecessary emails.
    It may seem obvious, but avoid sending unnecessary emails in the first place wherever possible. If something could be confirmed with a co-worker via a conversation in the office, this would help save energy. Using office tools such as Slack, Teams, and Basecamp is also a good alternative to email sending, as these tend to consume less energy.
  • Abstain from sending out a "Thank you" email.
  • Streamline your emails.
    Where possible, it is also a good idea to think about the volume of email recipients who receive any given message. Having many unnecessary people on an email chain increases the chance that the message is unread and sits in storage, thus consuming more energy.
  • Ensure the mailing lists you use are up to date.
  • Develop good email habits.
    The spam clogging up your inbox could also be a source of emissions. 49% of email traffic is considered spam, according to figures from Statista. With 239.6 billion messages sent worldwide, that's a lot of spam.
    Regularly emptying your recycle bin and spam folder frees up space on the servers that store email data and could help reduce the amount of CO2 produced by systems keeping us all online.
    Downloading an anti-spam tool will also help you reduce your email pollution. Many email hosts now offer you the ability to unsubscribe from newsletters and other emails from companies you don't read.

Email carbon footprint and related topics