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The Costly Backbone of Consumerism

Magazine #3 | Autumn 2023

The Costly Backbone of Consumerism

As is true of the internet in its entirety, digital advertising is boosting carbon emissions. Currently, there are nearly 2 billion websites online, and the number of advertisements on them is ballooning rapidly.

The digital world’s carbon footprint might even be larger than that of the aviation industry. Still, a recent study revealed that six out of 10 consumers are unaware that digital ads and internet browsing produce carbon emissions.

The online tracking-based advertising ecosystem is fueling the climate crisis in three ways:

First, the technical processes on which the collection of data and the building of user profiles are based increasingly rely on complex machine learning systems, which produce additional carbon emissions. Globally, the internet accounts for 4 percent of CO₂ emissions, with the energy required for digital advertising making a significant contribution to that total. Emissions generated by digital services are predicted to double by 2025.

Second, advertisements are designed to encourage us to buy things we don’t necessarily to need. A recent study by Purpose Disruptors, a network of advertising and marketing insiders pushing the industry to take responsibility for the emissions it drives, estimated that personalized advertisements have caused the UK’s per capita emissions to increase by 32 percent in 2022.

Third, tracking-based advertising helps spread misinformation, which leads to social disruption. The same algorithms that profile users for advertising purposes can also be used as tools for disseminating climate disinformation, fostering alternative reality bubbles and creating conditions that increasingly threaten democracy itself, all of which is incompatible with the development of fair and ambitious climate policy. Since this aspect has already received extensive coverage in other publications, this article focuses on the carbon impact of advertising technology and of the consumption it drives.

Wasting Energy on the Search for the Highest Bid

A single digital advertisement only consumes a relatively small amount of energy, but the prevalence of such advertising has a huge global impact. Ryan Cochrane, chief operating officer of the global AdTech platform Good-Loop, estimates that the advertising ecosystem handles 2,000 times more bids than the 8 trillion transactions undertaken by the New York Stock Exchange  on any given day. The Irish Council of Civil Liberties projects that the industry’s real-time bidding system places 178 trillion advertisements in the U.S. and Europe each year.

New data shows that the energy required for a single ad impression is equivalent to approximately one gram of carbon dioxide emitted. This value includes the energy consumption of user devices, data servers and ad servers. It includes activities such as data collection, processing, storage and management in addition to the creation of detailed user profiles. Many of the complex machine learning algorithms that transform raw data into actionable and valuable insights for advertisers are also extremely energy inten­sive. According to a recent report by Global Action Plan, online advertising accounts for about 1 percent of total global energy consumption.

The vast majority of that 1 percent is effectively wasted energy that leads to zero ads being placed due to the underlying auction system. For each of the trillions of advertisements placed each day, there are several prospective bidders – sometimes even thousands – for the slot in question. The business rationale behind this system ensures that the highest price is paid for each slot, but it comes at a cost: the AdTech ecosystem’s exploding emissions.

An additional aspect is the fact that much online advertising is fraudulent. Far from being a minor problem, the World Federation of Advertisers estimates that fraudulent advertising will soon be worth over $50 billion per year. Indeed, it is organized crime’s second largest source of income after the illicit drug trade. The AdTech industry estimates that the value of fraudulent advertising is around 4 percent of its own business value, while independent researchers have come up with numbers well above 25 percent. Given the vast number of online ads served every day, the total is significant no matter which estimate is correct.


Advertising is an industry generating hundreds of billions in revenue every year, which, as mentioned above, significantly boosts the carbon footprint of consumers by encouraging consumption. The New Weather Institute found that there was “sound empirical evidence” that advertising is indirectly responsible for “climate and ecological degradation through its encouragement of materialistic values and goals.” Indeed, those working in advertising must face the uncomfortable truth that “the better you do your job, the more damage you cause.”

Happily, an alternative is already available: To reduce the climate impact of AdTech, we must switch to contextual advertising systems. Such systems use the context of the webpage content and post contextually relevant advertisements to the webpage. Such context-based ads aren’t matched to the multitude of a website’s users, but only to the single webpage in question, thus decreasing the number of computing processes necessary and, by extension, the amount of energy consumed. Not only does contextual targeting obviate the need for collecting masses of personal data and building profiles. It also decreases the number of ad impressions up for bid, thus decreasing the amount of energy consumed by the online auction system.

We can’t expect the advertising industry to voluntarily move away from what has proven to be a cash cow. We urgently need policy makers to outlaw the targeting of ads based on personal data, similar to the provision of the European Union’s Digital Services Act provision banning the targeting of children. Only then can the climate impact of AdTech be significantly reduced.


Head of Accountability at 5Rights, a non-governmental organiation working on the rights of children and young people in a digital world

He joined 5Rights from the New Economics Foundation, where he led the Digital Economy Programme. Duncan has a legal background as well as a decade of experience working in the tech industry for Cisco Systems.