Quiet Bitcoin mining with immersion cooling and use of waste heat

Location: Somewhere in northern Germany

I have built a "heater" which digs Bitcoins for me and warms my living room at the same time. Since I spent quite a bit of time on this project and it wasn't clear in the beginning if what I came up with will work, I would like to present the project so you can benefit from my experience.

I run 2 hashboards. These have a hashrate of 9.4 TH/s and would generate 0.00000220 BTC / hour according to a mining calculator. With an electrical power of 0.78kW.

Let's say we produce 1000kWh of heat with the hashboards. Then we have to run the hashboards 1000kWh / 0,78kW = 1282 hours.

This costs us 0.27€/kWh * 1282 h = 346€.

We get 1000kWh in heat and 0.00000220 BTC/h * 1282 h = 0.0028204 BTC

So at a rate of 50000€/BTC we get 141€ in the form of bitcoin.

Compare this with gas heating:

1000kWh gas heat costs 90€

1000kWh Electric heat costs 346€ and we get 141€ in Bitcoin so 346€-141€ = 200€.

The rate of Bitcoin would have to be around 90000€/BTC for it to cost the same as gas heating.

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Gas price about 0.09€ / kWh

Electricity price about 0.27€ / kWh

Bitcoin price about 43700€/BTC

Green electricity share in the power grid about 45%.

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Hardware:

Antminer S9j (3 hashboards) with power supply.

30 liters tin bucket

20 liters Addinol white oil WX15

Radiator height: 60cm width: 80cm depth: 12cm

Fabric hose, pipe fitting etc.

Hot water pump

Small PC fan

Fan Simulator

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At first I wanted to operate the power supply in the oil (see the picture of the aluminum frame).

But since I did not know how the thing runs, I have the power supply first left out.

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Conclusion:

The system has been stable for a few days now. I usually use it in the morning and a couple of hours in the evening, when I am at home.

The fan of the power supply I have also throttled a little (5 diodes soldered into the line of the fan) so he is still a little quieter. The volume of the hot water pump is very low. This I operate with an old notebook power supply with 19V. I bought the 24V version, there is also a 12V version. The power supply is the loudest component.

The radiator I bought used. Keep in mind that in the radiator may be impurities which are then deposited in the bucket. This was not a big problem, but I recommend to consider this and maybe install a filter in the beginning. In the oil I also operate a small fan that circulates the oil. Thus, the temperature in the bucket is evenly distributed.

After about 3 hours, the system is at maximum temperature. The oil temperature is then about 58°C, the chip temperature of the hashboards is max. 86°C and the radiator is about 45°C. The outside temperature is about 0°C at the moment and the Bitcoin heater manages to keep about 21°C in the living room.

Next I will build a platform with casters and put the system on it. I plan to run the hashboards in spring with my own photovoltaic modules to reduce the mining costs.

It is an interesting project and I have gained some experience.

If you found this post helpful and maybe want to donate some satoshi here is my bitcoin address:

1DhNAhyd69PuqodLGCX4hz2EqGugFkqrPy

Otherwise, stay healthy and HODL

feel free to ask questions

Aluminum frame to support the hash boards in the oil

Current system with a pizza dough on the radiator ;-)

Warmwaterpump from Ebay

Fan simulator from Ebay

30L tin bucket from Ebay