Bitcoin Mining's Sustainable Energy Usage Surges to 52.4%

Bitcoin mining's sustainable energy usage has reached a significant milestone, with 52.4% of its power now coming from zero-emission sources, according to a new study by Cambridge University. This marks a substantial increase from the 37.6% reported in 2022, highlighting the industry's growing commitment to environmental sustainability.

The study, published by the Cambridge Centre for Alternative Finance (CCAF) through its Digital Mining Industry Report, provides detailed insights into the energy sources powering Bitcoin mining. Renewable energy sources such as wind and hydropower account for 42.6% of the sustainable energy used, while nuclear energy contributes an additional 9.8%. This shift towards cleaner energy sources is a positive development for an industry that has long been criticized for its environmental impact.

Natural gas has now surpassed coal as the primary energy source for Bitcoin mining, with its usage rising to 38.2% compared to 25% in 2022. Conversely, coal's share has decreased significantly to 8.9% from 36.6%. This transition is likely driven by the increasing availability and cost-effectiveness of natural gas, as well as growing environmental concerns.

The report is based on a survey of 49 mining companies operating in 23 countries, representing approximately 48% of the Bitcoin network's total hashrate. Participating firms included bitfarms, cleanspark, hut 8, IREN, MARA, and Riot. The study estimates Bitcoin's total electricity consumption at 138 TWh annually, roughly 0.5% of global energy usage, and calculates carbon emissions at 39.8 megatonnes, with a 24% year-over-year improvement in hardware efficiency.

In addition to the shift towards sustainable energy sources, the study also found that miners are taking steps towards sustainability beyond energy sourcing. About 86.9% of decommissioned mining hardware is either resold, repurposed, or recycled, with Bitcoin mining producing around 2.3 kilotonnes of electronic waste in 2024. This highlights the industry's efforts to minimize its environmental footprint and promote circular economy principles.

Geographically, North America dominates the Bitcoin mining sector, with the U.S. accounting for 75.4% of activity and Canada for 7.1%. Electricity remains the primary cost driver for miners, making up over 80% of operational expenses, with a median reported power cost of $45 per MWh. The report also noted that Bitcoin miners contributed to grid stability, curtailing 888 GWh of electrical load in 2023 to assist during peak demand periods.

The CCAF acknowledged that further research is needed into areas like methane mitigation, heat reuse, and broader social impacts such as employment effects. “By offering data from nearly half the global mining network, we aim to ground policy discussions in transparent evidence,” said Alexander Neumueller, Research Lead at CCAF. The report comes as Bitcoin mining's environmental impact remains a hotly debated topic, with recent studies and policy developments shaping the industry's future trajectory.