Investors and governments are growing increasingly concerned about the environmental impact of cryptocurrencies. 

For example, both China and Kazakhstan have banned crypto mining as a result of the huge amounts of electricity required, which is mostly generated by fossil fuels. 

As a result, investors are turning to more eco-friendly crypto coins which have skyrocketed in popularity and value over the past year.

So which low-carbon crypto coins performed the best in 2021 – and which of these eco coins are the most sustainable according to Co2 emissions and electricity consumption? 

Cardano was found to be the eco coin with the highest value, reaching a market cap of more than $38 billion in 2021. The Cardano blockchain, like many other eco-friendly cryptocurrencies, operates on a proof-of-stake mechanism, a greener alternative to the power-hungry proof-of-work protocols used by Bitcoin and Ethereum.

Polkadot ranked second with a market cap of $29.8bn, while Ripple came in third, recording a market cap of $25bn last year. 

RankEco coin2021 market cap

Fantom is the coin emitting the least amount of Co2 – only 7 tons per year thanks to its super-fast transaction times and energy-efficient software. Fantom’s carbon emissions are negligible compared to crypto giant Bitcoin’s whopping 114 mega tonnes annually. 

RankEco coinAnnual tons of Co2

The research was carried out by Traders of Crypto.

Twitter to trial crypto payouts

Twitter is to pilot cryptocurrency payouts for some of its monetised users.

US payments giant Stripe said the social media platform would be the first company to use its new feature, delivered via Ethereum scaling solution Polygon.

Users of Stripe’s app can now choose to receive payments in stablecoin USD (USDC) on the Polygon network.

Selected users of Twitter’s Ticketed Spaces and Super Follows programs will be given the option to cash out revenue through Polygon into USD via a number of Web3 wallets.

Once held in USDC, users will be able to exchange the value into any cryptocurrency they choose through the usual route of cryptocurrency exchanges.

Cryptocurrency shorts

People in Afghanistan and Ukraine have reportedly been buying cryptocurrencies such as stablecoins to protect their wealth – from the Taliban and effects of the war with Russia, respectively.

Bloomberg reports a sharp rise in the number of people going into rehab for crypto day-trading addiction, which experts likened to the effects of a drug on the brain caused by the high-risk stakes.

Cryptocurrency trading has fallen in the last two months despite star-studded ad campaigns for investment exchanges during the Super Bowl which cost millions of dollars.

Crypto prices

The overall market cap of the more than 19,000 coins is at $1.80 trillion, down from $1.89tr on Friday morning.

Market leader Bitcoin – the original cryptocurrency created by the mysterious Satoshi Nakamoto – is below $39,000 at the time of writing (7am UK) following an almost $2,000 decrease in value. BTC is about where it was a week ago.

Ethereum, the second most valuable crypto coin – created as a decentralised network for smart contracts on the blockchain – lost $150 to below $2,850. ETH, set for a huge upgrade soon, is 2% down over the course of a week.

Binance Coin is a cryptocurrency created by popular crypto exchange Binance to assist its aim in becoming the infrastructure services provider for the entire blockchain ecosystem. Its BNB token dropped $20 to $391, leaving it 2% down over seven days.

Solana is a blockchain built to make decentralised finance accessible on a larger scale – and capable of processing 50,000 transactions per second. Its SOL token fell $6 to $97 but it nevertheless moved above XRP in the valuation table by market cap. SOL is more or less where it was a week ago.

The XRP token of Ripple, a payment settlement asset exchange and remittance system, acts as a bridge for transfers between other currencies. XRP dropped 7 cents to below 67c, which leaves it 9% down over seven days.


Terra, described as a programmable money for the internet, dropped almost $5 to $89.96. Its payment token LUNA is 18% higher than its price a week ago.

Cardano is an open source network facilitating dApps which considers itself to be an updated version of Ethereum. Its ADA token, designed to allow owners to participate in the operation of the network, fell 6c to 86c. It is 3% down over the course of a week.

Avalanche, a lightning-quick verifiable platform for institutions, enterprises and governments, came out of nowhere months ago to break into the top 10 currencies. Its AVAX token fell $7 to $69.28 and is 5% down in a week.

Polkadot was founded by the Swiss-based Web3 Foundation as an open-source project to develop a decentralised web. Its DOT token, which aims to securely connect blockchains, dropped almost 90c to $17.60 and is 2% higher than its price a week ago.

Meme coin DOGE was created as a satire on the hype surrounding cryptocurrencies but is now a major player in the space. DOGE dropped close to 1c to below 13c while it is 6% down over seven days.

To see how the valuations of the main coins have changed in recent times – and for round-ups of recent cryptocurrency news developments – click here.

For valuations of the top 100 coins by market cap in US dollars, plus 24-hour price change, see below.