The World Wildlife Fund (WWF) is halting sales of NFTs after receiving pushback from environmentalists concerned about the industry’s carbon footprint

Earlier this month, the WWF announced the launch of their NFTs on the proof-of-stake (PoS) Polygon network in a tweet, claiming their choice of blockchain was environmentally friendly. 

“Releasing our NFTs on the eco-friendly Polygon blockchain, each transaction has the equivalent carbon emissions of a glass of tap water,” the WWF said at the time

Since that tweet, the Polygon network’s carbon footprint has come under scrutiny. 


“The carbon footprint of a Polygon transaction is close to 430 grams of C02. This is almost 2,100 times more than the optimistic estimate provided by the WWF, illustrating that Polygon is nowhere near as sustainable as claimed,” said Alex de Vries, founder of the Digiconomist website. 

Following the criticism, the WWF has reversed course on its NFT plans. 

“We agreed with our partners to bring this to a close last Friday. We recognise that NFTs are a much debated issue and we all have lots to learn about this new market, which is why we will now fully assess the impact of this trial and reflect on how we can best continue to innovate to engage our supporters,” the WWF told the Independent.

NFTs and the environment

The carbon footprint of proof-of-work (PoW) blockchains like Bitcoin and Ethereum is already well documented.


According to Cambridge University, the Bitcoin network consumes approximately 125 terawatt hours (TWh) of electricity per year—more than most of the world’s countries. In turn, the Digiconomist website estimates that Ethereum’s energy consumption currently sits at about 112 TWh. 

Most NFT activity relies on the Ethereum blockchain—which consumes an immense amount of energy. However, judging the carbon footprint of each NFT transaction—or even the broader NFT market—is more complex.  

This is because the energy consumption of proof-of-work blockchains is calculated by the energy cost related to mining new blocks on the blockchain itself, and not by individual transactions. 

According to a study published by the UCL Centre for Blockchain Technologies, proof-of-work blockchains are designed in such a way that their energy consumption “strongly correlates with its market capitalization, leading to an extreme demand for popular implementations [like Bitcoin or Ethereum].” 

Per the UCL study, PoS blockchains consume orders of magnitude less energy than PoW blockchains. However, as many PoS blockchains—like Polygon—are built on top of PoW blockchains, they continue to face criticism of the contributing role NFTs on PoS blockchains play in the crypto industry’s wider carbon footprint.

This is not the first time an organization has jumped off the NFT bandwagon amid concerns over the environment. Last month, Mozilla—the nonprofit behind the Firefox internet browser—announced a pause on crypto donations following backlash online. What's more, the Wikimedia Foundation—the nonprofit organization that funds Wikipedia—also faced calls to stop accepting crypto donations.

Daily Debrief Newsletter

Start every day with the top news stories right now, plus original features, a podcast, videos and more.