Bitcoin mining's annualized electricity demand reached about 190 terawatt-hours in December 2025, a 38% increase from June 2024, according to preliminary Cambridge Centre for Alternative Finance research. Hydropower has overtaken natural gas as the largest single energy source for mining, with low-carbon power now supplying 59.4% of the reported mix, up from 52.4%. Despite the cleaner mix, total estimated greenhouse gas emissions rose 20% to 48 million tonnes of CO2 equivalent, as efficiency gains from newer hardware did not fully offset the growth in total computing power. The research, based on survey responses covering just over half of global Bitcoin hashrate, also found that about 10% of miners have already allocated some power to AI or high-performance computing, with over 40% exploring the option. However, the shift to AI requires costly infrastructure upgrades that basic mining sites may lack. The findings highlight the tension between Bitcoin's growing electricity appetite and the grid's ability to supply low-carbon power, with implications for carbon accounting and renewable energy procurement in the crypto mining sector.
