Hut 8 and Bitmain have announced the launch of the Antminer U3S21EXPH, an ASIC miner featuring direct liquid-to-chip cooling within a U form factor. Hut 8 plans to deploy this model in the second quarter of 2025 through a hosting agreement that could expand its hashrate under management to approximately 33.5 exahash per second (EH/s).
The U3S21EXPH marks a significant development in ASIC computing by integrating cooling technology typically used in high-performance computing data centers. This miner shifts from the traditional “shoebox” design to a rack-ready U form factor, allowing deployment densities of up to about 180 kilowatts per rack. Hut 8 has developed a custom data center infrastructure to accommodate this new hardware, aiming to optimize performance and efficiency.
Currently, the best-performing miner on the market is the Bitmain S21 Pro, which runs at 234TH/s. The new miner is over three times more powerful and 3 J/TH more efficient.
Per the announcement, the partnership between Hut 8 and Bitmain extends beyond procurement. The companies collaborated on both technical and commercial aspects, with Hut 8 contributing to the miner’s development.
The hosting agreement features a fixed hosting fee and provides Hut 8 with an option to purchase all or part of the hosted machines within six months of their activation. This structure is designed to reduce upfront capital requirements and allow Hut 8 to assess market conditions before committing additional funds. If Hut 8 exercises this option fully, its self-mining hashrate could increase from 5.6 EH/s to approximately 20.6 EH/s.
Bitmain’s Vice President of Mining, Irene Gao, acknowledged Hut 8’s role in the development process, noting the company’s focus on cost-efficient procurement and operations. The collaboration is seen as a natural evolution of their relationship, aiming to define the future of mining technology.
Hut 8’s Chief Executive Officer, Asher Genoot, emphasized the innovative nature of the hosting agreement and its benefits, stating,
“Our team worked closely with BITMAIN to implement an innovative structure to commercialize the U3S21EXPH before it became available to the broader market.”
The deployment of the U3S21EXPH and the associated hosting agreement represent a strategic move for Hut 8. By integrating advanced cooling technologies and flexible procurement strategies, the company seeks to enhance its operational capabilities and financial performance.
