How adland can reduce emissions from streaming ads

Digital display and streaming ads produce 7.2m metric-tons of carbon emissions every year—that's enough to power 1.4 million US households for a year.

As budgets increasingly transition from linear TV to streaming platforms, the carbon footprint of streaming ads has surged, mostly due to the larger size of consumer devices like connected TVs (CTVs) and the significant energy required for data transmission of streaming content.

According to a report on sustainable advertising by Scope3, streaming ads produce more than double the carbon emissions of display ads. And as investment in streaming video ads continues to rise, this is becoming a growing concern. 

"The weight of creative assets is a major contributor to digital media campaign carbon footprints, with six times more CO2 emitted by a video creative than standard display on average due to its larger file size," says Audrey Danthony, co-founder of Impact Plus. 

To help marketers slash the emissions generated by their online video campaigns, global sustaintech platform Impact Plus launched a tool called Creative Optmizer earlier this year that reduces greenhouse gas emissions generated by a digital ad by an average of 30%.

The optimiser works by creating lighter creative assets, thereby avoiding a significant volume of emissions by reducing the load on servers, networks, and devices. To use the tool, marketers simply upload their videos onto the Impact Plus platform and receive lighter versions of the same asset.

"Each version is custom-made to suit the specific ad specifications of each platform, so it will reduce the weight of the video creative while maintaining its quality on each platform," says Danthony. "This gives advertisers a tangible lever to reduce emissions that can have a profound effect on a campaigns’ carbon footprint, without impacting campaign or brand performance."

Most recently, for one global retail brand who recently ran a YouTube campaign in India, the Creative Optimizer was able to reduce the video file size by 80%, resulting in a 70% reduction in GHG emissions, the equivalent of 11.9 tons of CO2 avoided. 

Syncing streaming ads with renewable energy 

Meanwhile, in Australia, data-driven media agency Hearts & Science worked with one of its clients, Opella Healthcare, to launch what it calls a Renewables Ad Engine. Launched in April 2024, the engine enables a more sustainable approach to delivering streaming video ads, particularly those on connected TVs. The Engine works by buying streaming ads when the energy grid is cleaner and more renewable on average, and less when it isn't. 

"By using our engine to deliver streaming ads when the energy grid has more renewable energy generation in it, this works towards the reduction of carbon emitted from our campaigns—with no impact to campaign metrics," says Ashley Wong, chief digital and innovation officer, Hearts & Science Australia. 

For their client Opella Healthcare, the agency was able to increase delivery of their campaigns during periods of relatively higher renewable energy generation by 76%.

"The premise is that if we are delivering our campaign during times with more renewable energy, the flow-on effect is that we are reducing our use of carbon-emitting energy generation such as coal—to deliver our streaming video ads," says Wong. 

Given the success so far, Hearts & Science are currently evolving their Renewable Ad Engine for 2025 to make it more automated and seamless for their teams to include and implement as part of their streaming video campaigns. 

"This is key for us as an agency, as it allows us to maximise the impact that we can have on emissions reduction," says Wong. "At the same time, while what we have created is proprietary—it is a concept that we have collaborated on and shared with tech partners like Scope3 and other media partners. There are vendors out there doing exciting things in 2025 which incorporate similar thinking around energy grid mix across media delivery—and we very much look forward to partnering with them to trial where relevant on our clients too."

June Cheung, head of JAPAC, Scope3, says that buying streaming ads at times when there’s more solar, wind and hydro energy in the grid is a starting point, but it doesn’t entirely solve the problem.

"Time-of-day targeting has limitations since renewable energy doesn’t always align with user behaviour—such as peak streaming times after 6pm when solar availability is low," says Cheung. "Relying solely on daytime ads could create a mismatch between ad supply and demand. We advocate for investments with low-emission media providers as a priority. This reduces emissions now, while setting the stage for progressively lower industry benchmarks, fostering a more sustainable advertising ecosystem."

Invest in low-emission media providers 

Furthermore, for advertisers aiming to reduce the carbon footprint of their digital media, Cheung recommends programmatic as a good place to start as it’s relatively straightforward and there are a number of tools out there that can help advertisers measure and then optimise for reduction. 

"Begin by ensuring that none of your media investments are directed toward climate risk inventory. This includes inventory that generates disproportionately high emissions, such as made-for-advertising (MFA) sites or problematic placements with excessive carbon footprints, which offer little to no value for your campaigns," says Cheung. "Beyond programmatic, channels like streaming video, digital out-of-home (DOOH), retail media, and others require proactive engagement with media providers. Communicate your goals clearly: let them know you’re committed to investing in media that achieves business outcomes sustainably. Ask, 'Do you offer low-emission media options we can invest in?'”

When it comes to sustainability, the advertising industry can definitely do more. However, this year, the industry has already taken significant steps towards meaningful action.

Top of that list has been the establishment of an industry standard to measure emissions. Ad Net Zero along with over 140 industry stakeholders including Scope3 participated in a collaborative project to align and agree on what’s included when measuring emissions in the ad industry. The result is the Global Media Sustainability Framework, which is aimed at providing media stakeholders with voluntary and pre-competitive tools to allow for the measurement of emissions more accurately across channels, geographies, and providers. It proposes tools for the media industry to better account for their scope 3 emissions, using media industry and climate-science based standards and best practices.

"Why is this exciting? It means we can move beyond the conversation of how to address the issue and instead focus on the next crucial step—what are we going to do about it?" says Cheung. "Big brands are leading by example. Coca-Cola, Kimberly Clark, Mondelez, Mars, and Kroger have taken steps to understand the impact of reducing carbon emissions in their media plans. Their results prove sustainability and growth aren’t at odds."

And as far as streaming ads are concerned, rewarding low-emission players with greater media investment is another effective way for agencies to incentivise sustainable behaviour. A report by GlobalData identifies media companies Disney, Bloomberg, Thomson Reuters, Sony, NewsCorp, Comcast and Schibsted as leaders due to their respective emissions reductions, reporting and targets for reaching net zero.

"The more the market invests in low-emissions media, the closer it moves to becoming the industry standard," adds Cheung. "This momentum not only normalises sustainable practices but also makes it easier for the entire ecosystem to progressively lower emissions, accelerating progress toward net zero."