Study shows quantum miners could save massive energy for blockchain.

Two scientists from the School of Computing at the University of Kent in the United Kingdom recently conducted a study comparing the energy consumption rates of current ASIC-based miners to proposed quantum-based solutions.

According to the team’s preprint research paper, the systems utilizing quantum computing outperformed standard mining rigs in terms of energy efficiency.

“We show that the transition to quantum-based mining could save about 126.7 TWH of energy – the equivalent of the total energy consumption of Sweden in 2020.”

As of May 2022, Bitcoin mining operations alone consumed more than 150 terawatt hours annually per the paper, highlighting the potential impact that the proposed quantum-based systems could have.

The researchers’ conclusions were based on experiments comparing three different quantum mining systems to an Antminer S19 XP ASIC miner.

The quantum mining devices were split between a system featuring a single layer of fault tolerance, another with two layers of fault tolerance, and one without any dedicated error-correction features.

As the researchers point out, in blockchain mining, error correction is not as critical as it is in most quantum functions. Errors create noise that functionally limit a computing system’s ability to produce accurate computations in most quantum functions. But in blockchain mining, success rates with state-of-the-art classical systems are still relatively low, making error correction less of an issue.

The researchers also note the ability of quantum-based systems to be fine-tuned over time for increased accuracy and efficiency, something classical systems lack.

Related: How does quantum computing impact the finance industry?

While quantum computing technology is still in its infancy, the specific problem of blockchain mining does not require a full-service quantum computing solution. According to the researchers, “a quantum miner need only perform a single task.”

Ultimately, the researchers conclude that it should be possible to build miners using existing quantum technologies that demonstrate quantum advantage over classical computers.

Despite the potential energy savings, it is noteworthy that the researchers focused on a type of quantum computing system called a “noisy intermediate-scale quantum” (NISQ) system.

According to the preprint paper, quantum miners should demonstrate “massive” energy savings at a size of around 512 quantum bits, or “qubits.” However, NISQ systems typically only operate with about 50-100 qubits, although there is no industry standard.

While the energy savings may be feasible, the costs of building and maintaining a quantum computing system in the 512 qubit range have traditionally been prohibitive for most organizations.

Only D-Wave and IBM offer client-facing systems in the same range (D-Wave’s D2 is a 512-qubit processor, and IBM’s Osprey weighs in at 433), but their architectures differ so greatly that comparisons between their qubit counts are ostensibly meaningless.