Environmental impact of bitcoin
The environmental impact of bitcoin has been characterized in the literature as significant, particularly due to its energy use, greenhouse gas emissions, and electronic waste. Bitcoin mining, the process by which bitcoins are created and transactions are finalized, is energy-consuming and results in carbon emissions, as 48% of the electricity used in 2025 was generated through fossil fuels while 52% was generated through sustainable energy sources. Moreover, bitcoins are mined on specialized computer hardware resulting in electronic waste. Scholars argue that bitcoin mining could support renewable energy development by utilizing surplus electricity from wind and solar., several empirical studies report an association between higher bitcoin-mining electricity use and worse environmental-sustainability indicators. Bitcoin's environmental impact has attracted the attention of regulators, leading to incentives or restrictions in various jurisdictions.
Greenhouse gas emissions
Mining as an electricity-intensive process
Bitcoin mining is a highly electricity-intensive proof-of-work process. Miners run dedicated software to compete against each other and be the first to solve the current 10 minute block, yielding them a reward in bitcoins. A transition to the proof-of-stake protocol, which has better energy efficiency, has been described as a sustainable alternative to bitcoin's scheme and as a potential solution to its environmental issues. Bitcoin advocates oppose such a change, arguing that proof of work is needed to secure the network.Bitcoin mining's distribution makes it difficult for researchers to identify the location of miners and electricity use. It is therefore difficult to translate energy consumption into carbon emissions., a non-peer-reviewed study by the Cambridge Centre for Alternative Finance estimated that bitcoin consumed annually, representing % of the world's electricity consumption and resulting in annual greenhouse gas emissions of, representing % of global emissions and comparable to Slovakia's emissions.
Bitcoin mining energy mix
Until 2021, most bitcoin mining was done in China. Chinese miners relied on cheap coal power in Xinjiang and Inner Mongolia during late autumn, winter and spring, migrating to regions with overcapacities in low-cost hydropower between May and October. After China banned bitcoin mining in June 2021, its mining operations moved to other countries. By August 2021, mining was concentrated in the U.S., Kazakhstan, and Russia instead. The shift from coal resources in China to coal resources in Kazakhstan increased bitcoin's carbon footprint, as Kazakhstani coal plants use hard coal, which has the highest carbon content of all coal types. Despite the ban, covert mining operations gradually came back to China, reaching % of global hashrate as of 2022., a CCAF report based on a survey of 49 bitcoin-mining firms reported their electricity mix as renewables, natural gas, nuclear, and coal. Research by the nonprofit tech company WattTime estimated that US miners consumed 54% fossil fuel-generated power. In 2023, Jamie Coutts, a crypto analyst writing for Bloomberg Terminal, said that renewables represented about half of global bitcoin mining sources.
Environmental effects of electricity use
A study in Scientific Reports found that from 2016 to 2021, each US dollar worth of mined bitcoin caused 35 cents worth of climate damage, compared to 95 for coal, 41 for gasoline, 33 for beef, and 4 for gold mining. A 2025 paper published in Nature Communications found that the 34 largest U.S. bitcoin mines consumed 32.3 TWh of electricity from Aug 2022 to July 2023, 33% more than Los Angeles. Fossil fuel power plants generated 85% of the increased electricity demand from these mines.The European Securities and Markets Authority and the European Central Bank suggested that using renewable energy for mining may limit the availability of clean energy for the general population.
A 2025 study in Scientific Reports of ten major cryptocurrency-producing countries found that Bitcoin mining's electricity use was linked to worse environmental sustainability. A larger share of renewables softened but did not eliminate these effects during the study period, and the impact on water use was limited. A 2025 peer-reviewed study in Sustainable Development that used monthly data from 2015–2023 and DARDL/KRLS methods reported an association between higher Bitcoin-mining electricity use and worse environmental sustainability in an SDG-framed measure; the authors characterized this as a risk factor for sustainability goals. A 2025 life-cycle assessment in ACS Sustainable Chemistry & Engineering quantified Bitcoin’s carbon, water, and land footprints, concluding that the network’s resource consumption poses sustainability challenges and highlighting the need for technological advances and cleaner energy sources.
Proposed mitigation strategies and debate
Reducing the environmental impact of bitcoin is possible by mining only using clean electricity sources. Bitcoin mining representatives argue that their industry creates opportunities for wind and solar companies, leading to a debate on whether bitcoin could be an ESG investment.According to a 2023 ACS Sustainable Chemistry & Engineering paper, directing the surplus electricity from intermittent renewable energy sources such as wind and solar, to bitcoin mining could reduce electricity curtailment, balance the electrical grid, and increase the profitability of renewable energy plants—therefore accelerating the transition to sustainable energy and decreasing bitcoin's carbon footprint. A 2023 review published in Resource and Energy Economics also concluded that bitcoin mining could increase renewable capacity but that it might increase carbon emissions and that mining bitcoin to provide demand response largely mitigated its environmental impact. Two studies from 2023 and 2024 led by Fengqi You concluded that mining bitcoin off-grid during the precommercial phase could bring additional profits and therefore support renewable energy development and mitigate climate change. Another 2024 study by Fengqi You published in the Proceedings of the National Academy of Sciences of the United States of America showed that pairing green hydrogen infrastructure with bitcoin mining can accelerate the deployment of solar and wind power capacities. A 2024 study published in Heliyon simulated that a solar-powered bitcoin mining system could achieve a return on investment in 3.5 years compared to 8.1 years for selling electricity to the grid, while preventing 50,000 tons of CO2 emissions annually. The authors note that proof-of-stake cryptocurrencies cannot provide these incentives.
Methane emissions
Bitcoin has been mined via electricity generated through the combustion of associated petroleum gas, which is a methane-rich byproduct of crude oil drilling that is sometimes flared or released into the atmosphere. Methane is a greenhouse gas with a global warming potential 28 to 36 times greater than. By converting more of the methane to than flaring alone would, using APG generators reduces the APG's contribution to the greenhouse effect, but this practice still harms the environment. In places where flaring is prohibited this practice has allowed more oil drills to operate by offsetting costs, delaying fossil fuel phase-out. Commenting on one pilot project with ExxonMobil, political scientist Paasha Mahdavi noted in 2022 that this process could potentially allow oil companies to report lower emissions by selling gas leaks, shifting responsibility to buyers and avoiding a real reduction commitment. According to a 2024 paper published in the Journal of Cleaner Production, bitcoin mining can finance methane mitigation of landfill gases.Comparison to other payment systems
In a 2023 study published in Ecological Economics, researchers from the International Monetary Fund estimated that the global payment system represented about 0.2% of global electricity consumption, comparable to the consumption of Portugal or Bangladesh. For bitcoin, energy used is estimated around per transaction, compared to for credit cards. However, bitcoin's energy expenditure is not directly linked to the number of transactions. Layer 2 solutions, like the Lightning Network, and batching, allow bitcoin to process more payments than the number of on-chain transactions suggests. For instance, in 2022, bitcoin processed 100 million transactions per year, representing 250 million payments.OECD notes that a direct comparison between blockchains, which are an infrastructure technology, and the energy consumption of financial sector activity may not be an appropriate comparison.