Is the ROI There? A Miami Panel on Hydro and Immersion Cooling

Is the return on investment really there for hydro and immersion cooling in Bitcoin mining? That was the first question put to a panel at Mining Disrupt Miami 2023, recorded July 25 to 27, 2023, and the answers came from a manufacturer, a large-scale miner and a cooling-system builder. Bitcoin traded at $29,144 that week. It is $82,535 today.

Irene Gao, VP of Mining at BITMAIN, went first. The company has deployed its hydro cooling infrastructure with clients in several regions, she said, and the ROI has been good. A second panelist, who is not named on the recording, said the cost per terahash is higher than air cooling, but longevity and uptime outweigh the premium, and the real saving is labor. As that panelist put it, "We're talking like, you know, 75%, 80% less touches."

Automation was the other half of the argument. A panelist running hydro containers from MicroBT and Heat Core described setting the dry cooler to auto mode, setting max power and frequency, and leaving the system to manage water pressure and flow. In that panelist's words, "Once you hit start, you literally walk away."

Taylor Monnig, VP of Mining Technology at CleanSpark, was asked for lessons learned. His advice was pre-planning, properly sized pumps and a clear picture of the electrical system. He also offered a warning from experience: "Dry coolers aren't going to work in the middle of the summer in Texas."

The panel split on two-phase immersion. Paul LI, CEO of Fog Hashing, said his team tested it, found the fluid, quality control and maintenance far more expensive, and dropped it. In his words, "So from my point of view, two phase won't be a choice for the mining industry." Monnig agreed it is too costly today, with fluid at about $300 a gallon and 3M facing PFAS problems, but expected denser chips and cheaper fluids to bring it back. He said, "I think it'll drive us moving away from the shoe box."

The hardest number came from a panelist who had just deployed a first megawatt of MicroBT and Heat Core hydro cooling in West Odessa, Texas. At 114 degrees ambient, hashboard temperatures held at 60 Celsius and chip temperatures in the low 90s. In the panelist's words, "So we're 20% cooler than the air-cooled units in Texas in full automation."

Gao closed by saying BITMAIN is working on two-phase immersion too and will share more at its Hong Kong conference in September. The full story is on Intelligence Disrupt at intelligencedisrupt dot com, and many more like it play around the clock on Bitcoin Radio.