Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Illustration: Sarah Grillo/Axios.

A new study predicts that a sharp increase in energy-hungry Bitcoin use will cause a surge in emissions of greenhouse gases, potentially dooming the world to an amount of global warming that would exceed the targets set under the Paris Climate Agreement.

Why it matters: Bitcoin has an energy problem, requiring high amounts of electricity to process transactions. Determining the implications of such energy use is of concern for climate scientists, particularly if this new currency takes off in popularity.

What they did: The study estimates that Bitcoin usage emitted 69 million metric tons of carbon dioxide in 2017, while accounting for just 0.033% of cashless transactions in the same year. They then project future emissions based on a variety of scenarios of growing Bitcoin usage in coming years.

The researchers, from the University of Hawaii at Manoa, found that Bitcoin could be responsible for greenhouse gas emissions sufficient to propel climate change past 2°C, or 3.6°F, above preindustrial levels within just the next 11 to 22 years.

  • As the study, published in Nature Climate Change on Monday, notes, a lot of Bitcoin mining takes place in China and other parts of Asia, which currently depend on coal for a lot of their electricity.
  • Therefore, if Bitcoin is increasingly utilized as a cryptocurrency, the authors project, emissions could skyrocket.

But, but but... The study makes a number of questionable assumptions, experts said. For example, the projections assume that the fuel types used to generate electricity will remain the same as they are today.

  • This ignores the rapid rise of renewables worldwide and phaseout of carbon-intensive coal plants from many countries.
  • They also didn't take into account the likelihood that Bitcoin mining will migrate between countries, potentially shifting from nations with a more carbon-intensive electricity base, like China, to cleaner ones, such as Iceland or the U.S.
  • Also, accurately predicting future use of a novel technology is difficult, and many observers expect Bitcoin to serve more as an investment vehicle than a currency.

What they're saying: Northwestern University’s Eric Masanet, who specializes in energy modeling, called the new study “fundamentally flawed,” in a statement.

“While the future growth of cryptocurrencies like bitcoin is highly unpredictable, we do know that the global electric power sector is decarbonizing and that information technologies — including cryptocurrency mining rigs — are becoming much more energy efficient. It appears the authors have overlooked these two latter trends in their projections, while simultaneously insisting on tremendous growth in cryptocurrency adoption, resulting in inflated and dubious estimates of future carbon emissions.”
— Eric Masanet, Northwestern University

Similarly, Lawrence Berkeley National Lab research scientist Arman Shehabi tells ThinkProgress that the study keeps certain factors the same while assuming a drastic growth in the use of Bitcoin. Shehabi noted that Bitcoin mining "has already increased efficiency by an order of magnitude or more in the last few years.”

Our thought bubble: The high energy costs and climate impact of Bitcoin mining is a legitimate ongoing concern, but specific predictions are only as good as the assumptions they're based on, and those assumptions — of rates of technology adoption, sources of energy, and efficiency of the applications — are very hard to nail accurately.

Scott Rosenberg contributed to this story.

Go deeper

Prosecutors begin closing arguments in Chauvin trial

Steve Schleicher, an attorney for the prosecution in Derek Chauvin's trial, began closing arguments on Monday by describing in detail George Floyd's last moments — crying out for help and surrounded by strangers, as Chauvin pressed his knee into Floyd for nine minutes and 29 seconds.

Why it matters: The jury's verdict in Chauvin's murder trial, seen by advocates as one of the most crucial civil rights cases in decades, will reverberate across the country and have major implications in the fight for racial justice.

Kendall Baker, author of Sports
3 hours ago - Sports

European soccer is at war

Liverpool celebrating its 2019 Champions League victory. Photo: Nigel Roddis/Getty Images

Europe's biggest soccer clubs have established The Super League, a new midweek tournament that would compete with — and threaten the very existence of — the Champions League.

Why it matters: This new league, set to start in 2023, "would bring about the most significant restructuring of elite European soccer since the 1950s, and could herald the largest transfer of wealth to a small set of teams in modern sports history," writes NYT's Tariq Panja.

Dion Rabouin, author of Markets
4 hours ago - Economy & Business

2021's expected earnings blowout begins

JPMorgan CEO Jamie Dimon. Photo: Mark Kauzlarich/Bloomberg via Getty Images

First-quarter earnings so far have been very strong, outpacing even the rosy expectations from Wall Street and that's a trend that's expected to continue for all of 2021. S&P 500 companies are on pace for one of the best quarters of positive earnings surprises on record, according to FactSet.

Why it matters: The results show that not only has the earnings recession ended for U.S. companies, but firms are performing better than expected and the economy may be justifying all the hype.