A fishy “fact” has been swimming around the internet for a few months, and recently reared its head on social media yet again:
“The emissions generated by watching 30 minutes of Netflix is the same as driving almost 4 miles,” according to the website Big Think.
Although computers and internet technology do use electricity — which is often but not always generated by fossil fuel burning — streaming your favorite show on Netflix, HBO, Hulu, or Amazon is not nearly as carbon demanding as driving a gas-powered car.
1. Streaming TV isn’t the problem
Some web activities connect to big data centers and run billions of Google searches each day or perform complex analyses — like the explosion in personal algorithms and big data that choose products to show you on websites — which require lots of computing and energy.
But streaming is different.
“Streaming is not something that’s computationally intensive,” said Vishal Misra, a computer scientist at Columbia University, who called the Big Think blog “clickbait.”
“Showing you the latest episode of Money Heist [on Netflix] is not the same” as a computer searching through troves of information at a data center, he emphasized.
When you stream Game of Thrones, the show isn’t streaming to you from the type of giant data center used by health care companies, Facebook, or banks, but from a different type of data center called a Content Delivery Network, or CDN, explained Misra. These places physically store the episodes so the shows’ data can be efficiently and reliably sent to someone pressing play. CDNs simply copy information (like a TV show), as opposed to asking computers to crunch numbers and search through massive banks of information, like at Google’s data centers. “[CDNs] replicate content all over the world in places close to you,” said Misra.
“The cost and carbon footprint (at for example, Netflix) for streaming is quite low since most content a user streams is cached [stored] on nearby CDNs,” agreed Tony Jebara, a machine learning researcher and former computer scientist at Columbia University. “Those costs are going down per stream consistently so they are slowly going away and becoming minimal.”
It should be noted that YouTube — with its 1 billion hours watched daily according to YouTube — also often uses CDNs for its most popular content. Additionally, live-streaming might be a little more energy-intensive than watching Netflix, but this pales when compared to the really compute-intensive tasks at a giant data center, explained Misra.
In our web-dominated society, data centers overall (even the giant ones) accounted for nearly two percent of U.S. electricity use in 2014, according to the most recent statistics used Department of Energy, which the agency still cites today. And overall, data centers today contribute just 0.3 percent of the world’s total carbon emissions.
It’s true that web use is exploding overall. That’s not going to change. But in a report released in May 2019, the International Energy Agency found that, although an 80 percent increase in data center traffic is projected over the next three years, energy demand is expected to slightly decrease “based on current trends in the efficiency of hardware and data center infrastructure.” (These efficiencies are further discussed below).
Big Think attributed their questionable statistic to an interview with Maxime Efoui-Hess of the French think tank The Shift Project, which advocates a transition to a “post carbon economy.” (This is certainly an important endeavor in a relentlessly warming world rife with lethargic efforts to slash the globe’s still rising carbon emissions.)
The Shift Project did not reply to multiple inquiries about their streaming versus driving claims.
2. Burning gas uses more energy
Even in 2014, when computers were less efficient than they are today, streaming was significantly more energy-efficient than driving.
A video streaming study published in the peer-reviewed journal Environmental Research Letters in 2014 found that streaming video for 30 minutes resulted in emissions of about 0.2 kilograms of CO2.
But driving for 30 minutes — based upon combustion emissions, gasoline production and transportation, and vehicle manufacturing for a car that gets 25 miles to the gallon — emits roughly 1.8 kilograms of CO2 over the course of four miles, explained Inês Azevedo, an associate professor of energy resources engineering at Stanford University.
So in this case, driving a car four miles produces nine times as much carbon pollution
“The claim from the study [cited by Big Think] doesn’t seem to add up,” Azevedo said.
Importantly, Azevedo pointed out this is a rough estimate and that streaming has become even more energy efficient in the last six years — so this calculation might be conservative.
The usual alternative to streaming (unless you have great public transit) is to drive to go see or buy a movie. If you care about carbon footprint, that’s just silly.
“In terms of carbon footprint, it’s far far better to stream than to drive to get manufactured physical media at the video store or to get to the movie theater,” said Jebara.
3. Computing is becoming way more efficient
Importantly, the electricity demands for transmitting information over the internet have been since the year 2000, according to research published in 2017 in the Journal of Industrial Ecology.
What’s more, Jonathan Koomey, a coauthor of this research, pointed out online, in response to the dubious Big Think statistic, that computing itself is generally becoming way more efficient. “Computations per kWh [kilowatt hour, a standard measure of energy use] now double every 2.6 years,” he tweeted.
4. Electricity is the easiest to decarbonize
Civilization has a profound carbon problem, with Earth’s atmospheric concentrations of carbon dioxide — a potent heat-trapping gas — the highest they’ve been in at least 800,00 years, but more likely millions of years.
Decarbonizing the world is an unprecedented challenge, but cutting out carbon emissions from generating electricity, which is required for streaming, is the easiest, lowest hanging fruit. That’s because there are well-known renewable energy and lower-carbon solutions, like wind, solar, and (for now) natural gas. For example, coal, the most carbon-intensive fossil fuel, is in sharp decline in the U.S. as it’s being replaced by natural gas and renewables. In some places, like California, renewables are increasingly dominant. The Golden State now gets nearly a third of its energy from renewables. In the coming decades, streaming in California will likely be a carbon-free activity.
What’s more, carbon emissions in the U.S. declined by around 2.1 percent in 2019, with emissions in the power sector falling by an impressive 10 percent.
In contrast, the transportation sector — teeming with SUVs and trucks — is the nation’s largest carbon problem. The transportation sector is the leading contributor of greenhouse gas emissions in the U.S. More driving won’t help.
So is leisurely streaming a movie after work (or delightfully binging an entire season of The Handmaid’s Tale) worse for the climate than driving a gas-powered car?
Everything, however, needs to be decarbonized for the globe to stop warming. Our data centers should be powered by ever-cheaper renewable energy along with battery storage, and our vehicles powered by low carbon technologies (like electric cars), said Stanford’s Azevedo.
“In terms of more big picture issues, I would say that my take is that the focus should be on decarbonizing all [energy] sectors as quickly as possible,” Azevedo said.