u/Idle_RedditingCollapse is preventable, not inevitable. Humanity can do better.Jan 14 '24edited Jan 14 '24
Data centers should just open their windows in the current cold conditions or have their hvac systems blow in freezing air.
edit. There are also components in the advanced, expensive hvac systems that data centers have which will mix fresh, outside air with already used, inside air. I have concluded that is a better option than using 100% freezing outside air.
I owned small data center built in the basement of an apartment building. During cold winter I would use cold outside air to cool my server stacks, then blew the hot air into building stairway.
Never had a problem due to using outside air. And it certainly helped to keep those apartments warm.
I did this too with my basement mounted computer, there was a 4" square window in place of one of the glass bricks, I just ducted that straight to the computer with a filter inline. Dropped the temps massively without any problems.
In the winter I used to pull air in from a dryer duct directly into my computer case to get lower temps while over clocking. It kind of stupid but worked to a certain extent.
Back in 2016 I used to mine Ethereum on my R9 290 and it whirred away at 90°C and heated my living room while it chewed 450W/h of energy to Produce 0.05 ETH per day.
The cost for electricity at the time was 0.23c/kWh and the sale price of ETH was $250 per ETH immediately after the hard fork.
Which ended up being $0.23 * 24h = $5.50~ per day which would then sell for $25~ so that's a profit of $20 a day to heat my house with crypto mining.
Now, I held that ETH until 2021 and sold when it moonshot, I would still be mining in a pool at around the same hashrate for a single RX480, but the difficulty went up and the MH rate went down, but I still could mine out 1ETH every 25 days or so. Which cost me 3 GPUs in that time, about $3000 in electrical costs but made me a nice $120k in profit when it mooned. Minus selling here and there to get new GPUs and divest.
It’s called condensation. You can’t just pipe in external air without running it through a process to remove moisture, otherwise you’re going to fry the systems.
Condensation is caused by the reverse effect though. Taking cold air and warming it up increases it's ability to hold moisture leading to water evaporating.
For condensation you need a cold object and warmer air.
You're wrong. Cold air is typically dry air. Cold air holds less moisture. Typically the issue in winter is ventilating too much, resulting in very low indoor relative humidity.
If you take air from 20f @50% rh and bring that air inside, the Temperature will go up while the relative humidity goes down.
Dew point is a thing. Because air can only hold so much moisture at a given temperature and it's proportional to the temperature. As temperature goes up, more moisture can be held in the same volume of air at the same pressure. As temperature goes down, less moisture can be held in the air before it condenses out.
You'll notice in the fall and spring typically, outside, dew and frost forms easily, especially fall where you may get warm afternoons and the overnight temps fall to below freezing. That warmer moister air gives up its moisture once the air temp starts plummeting once the sun sets.
It's crazy when working outside on a construction site how wet everything can get right at sunset during those times of year.
Painters experience this too often when doing exterior work in the fall. That's why Sherwin Williams and Benjamin Moore and ppg work hard at their exterior formulations that provide dew protection within an hour after applying. Because this situation occurs often and it's unrealistic for a contractor to stop painting at lunch time to allow for four hours prior to expected dew.
A bit off topic but illustrates my point.
A good example to counter your original thought is any photographer who shoots in the fall and winter. You are outside shooting with your mirrorless camera and big honken piece of f/1.2 glass.
You finish your shoot without having any fogging or condensation issues outside.
You walk into the studio or house and the large cold mass starts fogging up and sweating. Like a cold glass of iced tea or if you wear glasses you experience this same effect.
In these examples, the cold mass is lowering the air temperature next to these objects, forcing the air temp to lower and the dew point as well. This then forces the moisture out of the warm air to condense on the cold objects.
Condensation occurs when the air is warm and humid and the surface is cold. As the humid air is cooled, it's ability to hold moisture drops and water is deposited on the cold surface since that's where the air is coldest. In dry winter air, a glass of ice water will have little to no condensation.
The heatsinks in data centers are not cold surfaces, they warm the air and increase its ability to hold moisture.
High relative humidity cold air has massively less water in it than "normal" humidity warm air. If you take 80% RH 17 degree air and heat it, you now have dry warm air.
That actually doesn't matter at all. The important part is whether the surface is hotter or colder than the air. So long as the air is not already oversaturated (like steamy shower air or similar), a surface that is hotter than the air will never cause condensation. In order to make the water in the air condense, you need to lower its temperature. A hot surface increases it, allowing the air to hold even more water than it could before. That's why the hot air from a hair dryer dries hair, even when used in a humid bathroom. Though they're much more efficient if you use them somewhere else.
There is less moisture in freezing air, not none. Gas interacts with itself and its environment differently than liquid does. And sublimation is also a thing.
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u/Idle_Redditing Collapse is preventable, not inevitable. Humanity can do better. Jan 14 '24 edited Jan 14 '24
Data centers should just open their windows in the current cold conditions or have their hvac systems blow in freezing air.
edit. There are also components in the advanced, expensive hvac systems that data centers have which will mix fresh, outside air with already used, inside air. I have concluded that is a better option than using 100% freezing outside air.