The Carbon Footprint of Enterprise Email Marketing

If you’ve researched the carbon footprint of email, much of what you’ll read addresses an individual’s behavior. For email marketers, the math is a little different.

While email isn't the biggest source of carbon emissions, everything we do can have an impact. For example, does that “Thank You” email really need to be sent? Could an email have been a text, Slack, or [insert your company’s internal communication method here]? How many people need to be kept in the loop at all times and at all stages of a project?

However, if you're an email marketer, there's much more to consider, resulting in a much larger impact.

Email is still one of the most effective marketing channels out there in terms of engaging audiences. But with the rise of increasingly sophisticated automatic scanning, filtering, and quarantining, it's harder than ever to know if your emails are reaching your intended audience. This leads to the first consideration for marketers:

Problem 1: Wasted Email Sends

It would be terrific if every email we sent were read and engaged with, eventually leading to a sale. But that’s not reality.

We've analyzed dozens of marketing databases across industries and around the world. We've found that, on average, about 25% of emails are wasted - sent across global networks for processing with little chance of getting read. So regardless of anything else - size of a particular email, richness of formatting, how you want to calculate email "weight" to CO2e - a full quarter of the emails you're sending are likely completely unnecessary and wasteful. You can read more about this in our free e-Book on Dark Pool, but the results are pretty astounding. 

And yet those emails are still moving through global networks, copied multiple times across different systems for analysis, analyzed for malicious content or spam, and reported out before finally being delivered (maybe!) to a human for consumption. From there, a contact views and processes that email on perhaps multiple devices.

Problem 2: Campaign Email Size at Scale

Even if a single email on its own won't have much of a carbon footprint, when that email weight is multiplied across hundreds of thousands or millions of campaign contacts every day, it adds up. 

Here are the numbers: According to Mike Berners-Lee, a professor at Lancaster University, the average carbon footprint of an email in 2020 was between .03 g C02e and 26g C02e. At the low end, think of those text-only spam messages only a few lines long, routed and deleted by spam filters without any user intervention (shout-out to the fake Nigerian princes of the world for being so eco-friendly!).  

The good news is that many researchers have revised these numbers down, thanks to the increased efficiency of the data centers handling the emails.

The bad news is that those same researchers indicate that the larger screens used to read those emails may have thwarted these gains.  For context, the best-selling phone in 2010 was the iPhone 4, with a 3.5-inch screen; in 2022, the best-selling phone was the iPhone 13, with a 6.06-inch screen.

Our own research indicates that the payloads of a typical email are much larger than either a typical spam message or normal emails between people - something that few researchers have taken into account. Typical marketing newsletters with rich formatting and graphics are often 10 times as large.  On average, they're 75kb - without any attachments. 

All of that adds up. Especially since most of the carbon impact of an individual sending an email comes from the manufacture and use of the devices employed to create, store, send, process, and read that email.

  • Email Asset Creation - creative team uses devices and tools to create email assets, plan and design the campaign
  • Storage - storing marketing assets, email, as well as storage of those assets in the processing chain and in the recipient's inbox
  • Email Send Processing - resources and systems used to transmit an email, including quality filtering systems, relays, and analytics 
  • Email Delivery Processing - including incoming filtering systems, quarantines, and regular email delivery software
  • Manufacture of Devices - the devices required to run all of the above and to read email.

An email isn't just sent directly to a destination inbox. It goes through multiple redundant networks and processing steps before it's delivered (if it's delivered). So when that email is being sent to hundreds of thousands or millions of contacts during a campaign, the carbon footprint of that email takes on a new significance. When you add it up, that 75kb email could easily generate the equivalent of 10g CO2e.

But there are easy steps marketers can take to improve their efficiency and lessen their environmental impact, and they just so happen to dovetail nicely with best practices for email marketing.

Database Cleaning and Suppression

The first strategy email marketers can employ to reduce the carbon footprint of their email marketing campaigns is to address those wasted sends mentioned above.

The reality is that many contact databases include 25% or more problematic contacts: unresponsive, quarantined, fatigued, unreachable, or just plain fake.

These contacts will never recoup, never be a part of a positive ROI, and are just wasted sends from the standpoint of productivity and your company’s overall carbon footprint.

So your first step as an eco-friendly email marketer is to determine the scope of the problem, and Motiva can help.

If you’re not a Motiva Dark Pool customer who already has quick access to this information, you can sign up for a free database spot check, where we will show you exactly how many problematic contacts are in your database, wasting resources.

You can also use our Dark Pool Smart Suppress feature, a Decision service available on the Eloqua canvas that filters out these problematic contacts on-the-fly (no database maintenance required). This filtering reduces your carbon footprint and will increase your engagement rates.

Message Testing and Segmenting

1,000 engaged contacts are better than 10,000 unengaged, unreachable, or otherwise unqualified contacts. Make the most of your email sends by segmenting your audience and continually running message tests to boost engagement.

By segmenting your audience into groups most likely to respond to a particular offer or communication style, you’re giving your prospect what they want and reducing the number of wasteful sends.

The same logic applies to message testing (which happens to be a great way to surface audience segments).

Using Motiva’s message testing capabilities, you can create multiple versions of the same email, send them out to your audience segment, and Motiva will automatically stop sending the underperforming versions. As a result, message testing boosts your engagement metrics and provides your audience with a message that resonates and reduces the number of wasted sends.

By implementing these best practices, you'll improve your engagement metrics and reduce the negative impact your email marketing campaigns have on the environment.

Curious about your email carbon footprint?

  1. Check out our new email marketing carbon footprint calculator. Simply enter the size of your contact database, the percentage of unreachable contacts, and the number of emails sent yearly. Then we’ll estimate how many wasted sends and how many trees it will take to absorb the C02e generated by those.
  2. Install Motiva Dark Pool. We'll use your marketing platform's live data to tell you exactly how much you're wasting!


Want to see what Motiva can do for your email marketing team? Sign up for a demo today!

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