Environmental impact of an email

Understanding and Reducing the Carbon Footprint of Email 

When we think about carbon emissions, our minds usually jump to planes, cars, and factories—not the inbox. But in our digital age, even something as simple as sending an email has a carbon footprint. Individually, an email’s impact is minuscule, but when multiplied by the billions sent daily, the environmental cost adds up fast. 

In this post, we’ll break down the carbon footprint of email, why it matters, and most importantly—what we can do to reduce it. 

Emails, an indispensable part of modern communication, carry an often-overlooked environmental cost: a carbon footprint. This footprint arises from the electricity consumed at every stage of an email's journey – powering the devices used for writing and reading, the networks transmitting the data, and the vast data centres that store it. 

The Growing Impact of Digital Infrastructure 

While experts estimate that data centres currently account for less than 0.1% of the world's total carbon footprint (a figure dwarfed by, for example, the 20% attributed to cars), their emissions are on an upward trend. This growth is fuelled by the increasing demand for online media, including video calls, gaming, and streaming services, all of which rely on the same underlying infrastructure as email. 

The cumulative effect of individual emails is significant. Research commissioned by Ovo Energy in November 2020 highlighted this, suggesting that if every person in the UK sent just one fewer email per day, the nation could cut its carbon output by over 16,400 tonnes annually. 

The Complexities of Calculating Email Emissions 

Pinpointing the exact carbon emissions of a single email is challenging due to numerous variables: 

• Device Type: The energy consumption of the device used (e.g., a new smartphone vs. an old desktop). 

• Usage Time: The duration spent writing and reading the email. 

• Content: The inclusion of images, large attachments, or complex signatures with logos. 

• Transmission & Storage: The efficiency of the networks and data centres involved. 

Given these factors, estimations often rely on a range. Mike Berners-Lee, in the 2020 edition of his book "How Bad are Bananas?: The Carbon Footprint of Everything," places this range between 0.03g CO2​e (carbon dioxide equivalent) and 26g CO2​e per email. This is a reduction from his earlier estimates, reflecting improvements in device and data centre efficiency. 

Illustrative Email Carbon Footprints (CO2​e): 

• Spam email (filtered, unread): 0.03g 

• Short email (sent/received on a phone): 0.2g 

• Short email (sent/received on a laptop): 0.3g 

• Long email (10 min write, 3 min read, laptop): 17g 

• Bulk email (e-shot platform, 10 min write, to 100,000 people): 15g 

• Individual emails (Desktop Outlook, 10 min write, to 100 people individually): 26g (Note: This implies 26g per email, or a significantly higher total if sending 100 such emails). 

e-shot™: A Strategic Approach to Lowering Email Carbon Emissions 

Specialised platforms like e-shot™ offer a more carbon-efficient way to manage email communications, particularly for high-volume sending. This is achieved through several key strategies: 

1. Energy-Efficient Infrastructure: 

• Since 2018, e-shot's infrastructure has been hosted in one of the UK's most energy-efficient data centres, powered by 100% carbon-neutral, renewable energy from UK wind farms. 

• The platform utilises the latest eco-friendly, new-generation servers with the highest possible energy efficiency ratings, which are regularly monitored and updated. 

2. Optimised Sending Processes: 

• Employing a 'built-for-purpose' system for high-volume email delivery is inherently more efficient than sending individual direct emails or using standard mail-merge technology. 

3. Enhanced Engagement and Reduced Waste: 

• e-shot automatically manages engagement by excluding unsubscribes and hard bounces, significantly reducing the number of unnecessary emails sent. 

• The platform's preference centre allows subscribers to control their interests. This not only aids data protection compliance but also improves engagement and reduces email wastage by ensuring recipients only receive relevant content. 

4. Efficient Campaign Creation: 

• Predefined campaign templates save considerable time and computing power in creating pre-approved, engaging, and consistently branded campaigns. 

• Reusing existing designs further minimises creation time and the associated energy consumption. 

• Automatic subscription management via sign-up pages reduces the computing time spent on list generation and maintenance. 

5. Minimising Unnecessary Replies: 

• Promoting practices like "accept my thank you" to avoid trivial replies, and the ability to use a 'no-reply from' address, can further cut down on email traffic. 

Forfront's Commitment 

Forfront's dedication to reducing its organisational carbon footprint is intrinsically linked to the development and continual enhancement of the e-shot platform, its functionality, and its infrastructure, all contributing to a more sustainable digital environment. 

Last Updated: May 23, 2025