I started the project in January 2018 on the Bitcoin mining hype by purchasing a few ASICs from Bitmain. ASICs initially were located in the apartment but shortly were moved to the heat-insulated container with AC connected to industrial electricity in Jebel Ali (MFC). In April 2018, an overheating problem was raised and fixed by airflow management, but in May 2018, serious investments are required into the air cooling system. I had to stop mining until October 2018 or find a solution.
Air cooled mining farm
The cooling solution should match the following criteria: inexpensive, reliable, low power consumption, low running costs, not flammable, self-regulated and remotely manageable. I rejected a single-phase immersion cooling solution based on mineral oil because it doesn’t match all mentioned criteria, i.e. it’s flammable, requires tap water, a facility should be supervised during hot days (as oil can be physically heated up to 230C). 2-phase immersion cooling solution matched all criteria and looked more reliable due to the passive cooling process (liquid-> heating -> evaporation-> natural vapor cooling-> liquid). This liquid (NOVEC 1230) normally used in fire suppression systems as a fire fighting agent.
Triple heat exchange process
However, this product wasn’t available for sale because Bitfury Group acquired Allied Control for $200M in 2015 and focused a new subsidiary on in-house projects. Technically the process looked more or less clear, and I started to build my CoolTank in July 2018. I placed service/purchasing orders in Russia, China, Germany and the United States. Everything was delivered to Dubai in January 2019.
45 hashing boards without heatsinks from Bitmain’s Antminer S9
The prototype on the CoolTank was put into operation in March 2019 and still running.
Prototype in operation
Since that moment I had no maintenance, no failures, no problems. General parameters of the CoolTank:
ASIC S9 Bitmain 13.5Th
Hashing boards 45 pcs.
Mining power294 Th
Electricity 30 kW
Cooling 3 kW (pump, fan, AC)
Controls / safety / monitoring temperature via Blynk IOT, WebCam, emergency shutdown by signal from liquid level sensor.
Axial fan on dry coolier
Temperature sensor controls fan speed via Frequency converter.
Project vision. The next step is to implement the experience of designing, building, testing and using it into a formal “lessons learnt” document. The CoolTank 2.0 will be available for small scale mining (garage use).
>Manufacturing cost reduction>
>Tank on wheels
>Hot water utilization
Having done CoolTank 2.0, we’ll provide a range of models for different clients: mining at small and large scale, HPC custom solutions for data centres.
Cryptocurrency mining is just one possible use case on the CoolTank and its 2-phase immersion cooling technology. Artificial intelligence development and implementation will provide a considerable demand for cost-effective HPC cooling solutions like the CoolTank.