In the current Bitcoin mining machine manufacturing industry, miners can no longer achieve a great improvement in mining efficiency simply by purchasing new machines. At the same time, under the current macroeconomic environment, the global economy is in recession and the computing power is steadily rising. Therefore, new ways must be adopted to maximize the mining efficiency.

Figure 1: Update and Development of Bitcoin Mining Machine Energy Consumption and Efficiency in 2009-2020

So how to achieve it?

The first thing to mention is the rise of liquid-cooled mining as one of the main trends for 2021 and 2022. This article deeply discusses the significance of liquid cooling systems for Bitcoin mining, the advantages and disadvantages of liquid cooling systems, the applicable objects of liquid cooling systems, and the future of liquid cooling mining.

What is the liquid cooling system of the miner？

In a liquid cooling system, the components of the Bitcoin mining machine (usually the hash board) are submerged in a dielectric coolant, and the mining machine chips are kept at a constant low temperature, thereby increasing the efficiency and service life of the machine. In the traditional sense, miners generally use an "air cooling" system, that is, using exhaust fans and a dedicated HVAC system to adjust the mining machine to achieve the purpose of reducing the temperature of the chip.

This medium coolant is an engineering fluid with good thermal conductivity and insulation. Since the fluid has a stronger thermal conductivity than air, the use of coolant can achieve the purpose of cooling the power board faster. The focus of mining operations under liquid cooling systems is to ensure that the fluid flows through the hash board at an optimal flow rate, thereby ensuring that the chip temperature remains low.

Advantages of mining under liquid cooling system？

For the benefits or advantages of deploying these systems, their proponents summarize the following points:

Noise reduction: An air-cooled miner typically emits a high-pitched hum at a pitch of 70-85 decibels, but immersing the machine in a dielectric fluid can eliminate a lot of noise. This may be a much-needed positive factor for home miners who live with their families, or miners with larger mining scales near residential areas.

Improve machine performance: The liquid cooling mode allows miners to overclock the miner to generate higher overall computing power, while improving heat dissipation due to the thermal conductivity of the coolant, allowing the chip to be kept at a moderately low temperature. Removing the fan also improves energy efficiency, as the fan draws power from the machine in an air-cooled system that could otherwise be used for computing power.

Extended machine life: With the correct settings, the coolant allows the machine to output computing power at an optimal temperature, and the computing power hardly deviates, thus extending the life of the mining machine. In an air-cooled system, air particles can build up on the chip over time, reducing machine performance. The liquid cooling system eliminates this concern, as the hash board is not exposed to the open air in this mode.

Deployment Costs and Disadvantages of Liquid Cooling Systems？

Despite the advantages of liquid-cooled mining systems, they are not suitable for all mining operations. This is because the initial capital investment expenditure is too high and the expertise required compared to air-cooled operation.

Air-cooled systems require dedicated air storage tanks, dielectric coolants, heat exchangers, pumps, sensors, and other components, while miners deploying liquid-cooled systems must bear the same costs as the equivalent air-cooled operations above. Depending on location and size, upfront capital investment may result in a reasonable return on investment cycle for miners

Figure 2: Comparison of deployment costs between air-cooled systems and immersion cooling systems

Application of liquid cooling system among listed mining enterprises

Many large listed miners have made huge investments in liquid cooling facilities, such as:

Argo Blockchain: plans to deploy a 200 MW liquid cooling system at its Helios[1] facility, which is designed to accommodate liquid cooling equipment.

RiotBlockchain: The company’s Whinstone[2] facility has 200 MW of machines that are either already operating under liquid cooling or are planning to do so. Riot also recently announced that it will build a large 1 GW facility in Navarro County, Texas[3], where it plans to deploy a liquid cooling system.

CleanSpark: Publicly disclosed in late December 2021 that they are building a 20 MW liquid cooling facility in Norcross, Georgia[4]. Home miners are also beginning to dabble in liquid-cooled mining. Some people are very creative in the deployment of liquid cooling systems, and even connect to HVAC systems and swimming pool heating systems.

Many Telegram communities also focus on home mining, including Immersion Cooling Technology Talk[5] and Home Mining Wizards[6].

Will liquid-cooled mining be the future of Bitcoin mining?

As mentioned above, before investing in a liquid cooling system, miners must balance the expected benefits against the additional cost of system deployment. In desert climates such as Texas and Dubai, where the air is dry, the incentive to deploy liquid cooling systems will also be stronger in order to prevent air and dust particles from affecting mining operations. Conversely, Genesis in northern Sweden has a cooler climate and relatively few concerns about air quality and filterability.

As the Bitcoin mining and energy industries continue to merge with the dielectric fluid market, large petrochemical companies such as Exxon Mobil may come to our attention. These companies are fully capable of producing engineered fluids themselves, and businesses like ExxonMobil have long since expanded into flare gas mining, but we don’t seem to have seen their full involvement in Bitcoin mining yet.