Post
Topic
Board Mining
Re: keep a small mining farm cool with only air conditioners.
by
mikeywith
on 04/07/2023, 23:54:58 UTC
No, the efficiency actually changes:



TC is Capacity PI is power consumption.
It's a pain in the ass-protected pdf file, but I'm pretty sure even your model has the same kind of manual.
Again, look at the pipe length, this rating above is for 5m linear, and once you count elevation it's a mess.

Couldn't find a similar manual on the AC, the distributor of said brand guaranteed that the BTUs labeled on the AC will be achieved as long as the outside temp is below 52c.

Anyway, looking at the specs you posted, you can clearly see that the AC  has the highest TC when the room is hot and the outside temp is cold, so the hotter the room the more the cooling capacity, and, the greater the difference between in and out temp also the greater the cooling is, which makes sense, and that's what I picture the farm to look like, always hot inside - warm to cool outside.


It will bring the room temperature slowly up till it reaches the exhaust temperature at which point they will probably shut down themselves.

Quote
Let's look at it from the thermodynamics point of view as heat is just energy:

At one point you have one extra unit of produced heat in a unit of time, if this process goes continuously in a closed environment, after 1000 units of time it's 1000 extra units of heat. In a million units of time one million units of heat!
This will not stop at any point if we don't assume the equipment will melt itself because you're still feeding more heat in that room every second than you extract, 10C, 40C,
100C, 300C it's like blowing into a balloon, the heat has nowhere to go.
Of course, this is in a perfectly sealed environment, so there is heat escaping the room through the floor and the walls

There is nothing that can perfectly store energy in its heat form, the better the insulation the harder for heat to escape, but still, heat will always escape the room as long as the outside temp is is cooler, in the above example I gave, if 1 ac is turned on heating mode in a closed room, there is no way it would heat the room to melting point, in fact, if storing heat was that easy, then in the winter we would just use a small 1 ton BTU to heat a whole building, just wait for temps to keep rising since units of heat will keep accumulating, but we know this isn't the case, which is why we need to size cooling and heating and account for all the losses.

Quote
but if we talk about 30KW extra there is no way you will reach an equilibrium before you melt everything!
Especially since you also want to soundproof this room which will add to insulation and make less heat able to escape through the walls.

That's true, the 1 AC example is pretty "misleading", the more energy inside the room the hotter the room gets, there is limited energy/heat that can escape the room per unit of time, all depending on the insulation, sun, wind, outside temp, I'd imagine if you run a miner in a closed sealed room where outside temps at -40 the room would still be in a negative temp, while if you run it in the same room when temps outside are 40c, the pace/amount of heat leaving the room will be a lot lower, the potential difference between inside and outside is key.

With that said, I will by no means gamble with anything less than a 1:1 ratio at least for the initial feasibility study, in fact, it would be wise to assume that even 1:1 ratio isn't good enough and there will be days when we would have to lower the miner's frequency as Phill mentioned, there will be a lot of trial and error.



Thanks for your input Powell, do you recall the total power consumption of your farm vs BTUs?

For the humidity part, the place is very dry, there should be no issues with humidity at all.

As for the noise coming from the compressor /outside unit, it should be manageable, I checked a unit running and it was at 65 decibels at pretty much close to distance, noise levels will increase by 3 decibels every time the noise source is doubled, so 10 of them will output 75 decibels, that's a lot but still a lot less noise than a single miner doing that fan test, I doubt we will face issues with the noise coming from the ACs, I am more concerned about those Whatminers, since a single unit does 84 db when fans are at 100%, 50 of them will do close to 101 dB, I have exactly no way of knowing how much the insulation is going to reduce, but we kind of need the noise to be below 75 dB, could get away with a bit higher, but we will see.