Quantum Attack on Bitcoin Mining Would Need Star-Level Energy, Study Finds

A quantum computer would need the energy output of a star to successfully attack Bitcoin's mining network, according to research published by academics at MIT and the University of Cambridge. The study, released this week, concluded that a practical quantum attack on Bitcoin's proof-of-work system remains beyond foreseeable technological capabilities.

Market Context

Bitcoin has been trading in a tight range around $65,000 over the past month, while the network's hash rate has climbed to a record 300 exahashes per second, underscoring heightened mining difficulty and robust security. The broader crypto market remains sensitive to regulatory signals and energy consumption concerns, with institutional investors closely watching network resilience.

Analysis

The researchers modeled the computational requirements for a quantum miner to outpace the current proof-of-work competition, estimating that a machine with roughly 10 million stable qubits could need to operate at power levels comparable to the Sun's luminosity—around 10^26 watts. Such an energy demand would exceed the entire global electricity consumption by orders of magnitude, making the attack economically and physically implausible. The analysis further notes that even with rapid advances in quantum hardware, achieving the necessary qubit fidelity and error correction remains a multi-decade challenge.

Key Numbers

- Energy required for a theoretical quantum attack: ~10^26 watts, equivalent to a Sun-like star's output.

- Bitcoin network hash rate: over 300 exahashes per second (EH/s) as of early 2026.

- Estimated qubits needed for a viable attack: approximately 10 million stable qubits.

What to Watch

Market participants should monitor developments in quantum computing hardware, particularly improvements in qubit count and error correction, as these will determine when—or if—a quantum mining threat becomes plausible. Regulatory bodies are also expected to scrutinize the energy footprint of crypto mining operations, potentially influencing network consensus mechanisms. The next Bitcoin halving, scheduled for 2028, will further test the economic incentives for miners as block rewards decline.