It’s something that most of us wouldn’t even notice, but streaming video in standard definition, rather than hi-def or Ultra HD, could have a huge impact on the planet.
A campaign launched by Earth Day this year aims to raise awareness of the problem – and could be a "plastic bag moment" for thinking about our digital carbon footprint, says Tom Cosgrove, chief creative and content officer at Earth Day.
Scientists at the Royal Society say streaming a video in Ultra HD on a phone generates more than eight times more emissions than standard definition.
Experts have suggested that switching to standard definition could cut emissions from streaming services by up to 5% – the carbon emissions of YouTube alone equate to more than 10 million metric tons of CO2 every year.
This year, Earth Day called for standard definition to be renamed "Earth Definition", to raise awareness of the environmental impact of streaming.
"Most video viewing is now being done on a mobile device, as opposed to a large screen TV, it’s as high as 70% on some platforms," said Cosgrove.
"The reality is that you can’t really see the difference between something that’s playing in 4K and something playing in standard definition when it’s on a screen in your hand.
"There’s a cost to 4K streaming, and the idea here is that there’s a way you can contribute as an individual. We’re also trying to encourage all the other people in the process of delivering that video to you – the streamers, the ISPs, the data centres – to think about their carbon footprint."
Video is an increasingly large part of what we do online, with 82% of all internet traffic projected to be video by 2022 – and 5 million years of video content streaming or being downloaded online each month.
"When COVID arrived, there was a rapid transition to a much more digital economy," Cosgrove said. "A lot of things that were going to happen arrived much, much faster."
He said Earth Day hoped that people would start to think about their digital carbon footprint in the same way people now naturally think before using a plastic bag.
Cosgrove said: "For us, it’s similar to how you think about the impact of dropping litter, and picking up a plastic bag.
"Reducing one plastic bag has a positive impact – a small one – but hundreds of millions of them have a huge impact on our planet.
"We hope that this campaign is a stepping stone into awareness of digital carbon footprints.
"It’s something that everyone can do quickly, and on the flip side of the distribution pipeline, streamers and video companies can also make changes quickly."
Other digital technologies have huge carbon footprints, with the "mining" computers used to create bitcoins consuming huge amounts of power and often relying on fossil fuels.
Bitcoin mining consumes as much energy annually as the Netherlands did in 2019, according to data from the University of Cambridge and the International Energy Agency.
Cosgrove says that the campaign had already seen support from YouTube streamers and even from video companies.
"This campaign touches everybody, because just about everybody is watching video," he said. "Immediately, it started to pick up interest. Vimeo jumped on it and said, 'This is a great idea.'
"We have streamers going out and talking about it, we’ve had a lot of interactions on social media. It’s already connecting with people.
"It's one of those things where there's a benefit without really any cost to you other than just flipping over to Earth definition on your phone."
Cosgrove said Earth Day hoped to persuade streaming services and video platforms to make it simpler by making a button to switch to Earth definition as a default option.
He admitted, though, that there is still a place for hi-def and even Ultra HD.
"If I’m watching my favourite TV show on an 80-inch television, I’ll definitely notice the difference, and I want to watch in a higher definition.
"It’s just when I’m watching on a four- or five-inch screen in the palm of my hand – I won’t be able to discern the difference at all."
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