Bitcoin topped the list of the most-polluting cryptocurrencies. According to the report released by ForexSuggest.com, it uses 1183.58 kWh per transaction, an equivalent of 0.88769 ton of CO2. The runner-up Polygon uses 90.18 kWh per transaction, which equates to emitting 0.06764 ton of CO2 – an order of magnitude less than the most popular currency.
Dogecoin, which ranks seventh on the list, uses "only" 0.12 generating 0.00009 ton of CO2 – incomparably less than its competition. Ethereum ranked low due to its transition from energy-greedy Proof-of-Work to Proof-of-Stake last year.
The report's authors also calculated the number of trees required to offset the cryptocurrencies' environmental impact. It turns out that to nullify Bitcoin-related annual emissions, it would be necessary to plant as many as 431.6 million trees. Below you can find the figures for other top-dirtiest cryptocurrencies.
The only "dirty" ranking where Bitcoin scored second place is the one relating to the rate of increasing emissions. Cardano's "progress" was unparalleled, with 113% year-on-year increase compared to Bitcoin's 52%. On the other hand, Ethereum scored delightful -100%, which is obviously an approximation, quite illustrative of PoS's ecological advantage over PoW.
The low energy-intensive coins list is topped by Stellar, with IOTA, Nano, Ripple XRP, and Chia following.