Useful lifespan of mining hardware is less than a year. If "high sulfur content" corrodes them in 2 years, nothing of value is lost.
A prime example for many fake claims made here, which are not based on any facts and lack sources. "Thus it was a surprise to the industry when electronics in high sulfur industrial environments would fail rather quickly, some within 4 weeks of being put in service; replacement systems would do the same. Most failures would occur in 2-4 months." - my point with potentially not being able to reuse PSUs, switches, etc. is still valid, as well the risk on reliability of mining operations.
http://www.dfrsolutions.com/pdfs/2007_08_creep_corrosion_on_lead-free_pcb_in_high_sulfur_environments.pdfAs for not installing in high-sulfur areas: Well, what experience do you have with building mines? Have you ever created a weighted multi-factor comparison list? It's not only electricity costs and climate. There are local labor costs, logistics / customs duties for importing hardware produced in China for example, general tax situation, or even as simple as that you don't want to move to another city/state/country, etc. I'm not saying that China is an ideal location, but there are many factors at play when choosing a mining location. So when you posted an open air 'chicken farm' mining cluster in China as example for cheap mining facility, then I was merely pointing out the related drawbacks specifically on that example. Open air will inevitably reduce reliability due to dust, pollution, humidity, etc. Then again, setting up a real building will cost more. Why do you have to restrict yourself from potentially lucrative locations if there is a container solution which is globally usable? Oil-rich middle-eastern countries have very cheap electricity and often zero tax. But too bad - open air facilities wouldn't work there with electronics getting the occasional sand blasting with the next storm, next to 50C/122F ambient air temperatures in summer.
@Jimmothy: Stop being retarded. Of course air cooling has drawbacks, air's thermal conductivity is very low compared to, oh, water and copper. To counter that, it also happens to be outrageously cost-effective.
Finally (and this will no doubt be news to you), both water and immersion cooling are simply an intermediate stage of air cooling, since the final heat exchange is still done between cooling tower and air.
Yes, walking is cheaper than driving a car - but it depends on your specific application: It may be just not suitable for anything more than 50 miles and/or if you need to be anywhere faster than walking and/or transport stuff. Same with air cooling, water cooling, etc. The higher the density and TDP, the more air or water flow are required due to the previously mentioned limits on heat transfer per medium - it gets more difficult, more effort/energy/costs required. I even had to run computational fluid dynamics simulations using COMSOL on multiple heat sinks in series to see effects on pre-heated air from front rows of heatsinks on heatsinks at the back - such setups require much more air flow than small single row setups. Studies like these show how insane it gets if you approach 20kW per rack:
http://www.apcmedia.com/salestools/sade-5tnrk6/sade-5tnrk6_r7_en.pdf"Remove 2,500 cfm (1,180 L/s) of hot exhaust air from the enclosure [...] For reference, carrying 2,500 cfm (1,180 L/s) in a 12” (30 cm) round duct requires an air velocity of 35 miles per hour (56 km/hr)." - that's like holding a dinner plate out of the window while driving, just imagine the energy wasted to establish that... Yes, there are big industrial fans. But we need to consider total cost of ownership, including CapEx AND OpEx - inevitably, you will need to provide a very high air flow and maybe even chilled air to cool down sufficiently - both requiring a lot of electricity. As jimmothy pointed out already, average PUEs (and OpEx) of air conditioned installations or even cheap fan installations are MUCH higher than 2-phase immersion cooling.
I have as well calculated the pressure drop losses for multiple closed loop water cooling systems myself using Darcy-Weisbach equations, incl. all pressure losses per every elbow, valve, reducer, etc. Just running water in a big pipe won't get you anywhere, due to lack of surface area to mount your chips on. So water blocks are needed as interface to isolate water from electronics at the same time (but introducing more thermal resistance as well). And to get down from big pipes, branching out into multiple smaller water blocks, will lead to big pressure losses. This again requires not only very high water flow, but as well much stronger pumps using much more electricity. It's not just theory, I could calculate it down to fractional kW for given water cooling system. Even the heat pipe you are referring to has its limitation due to multiple thermal resistances before the heat even reaches the working fluid. And again, the higher the TDP, the bigger those heatsinks with heat pipes (e.g. notebook vs. desktop CPU).
With 2-phase cooling you can easily transport a lot of heat away from the small chips even with extremely high TDP. THAT is the key difference and why W/m
2K matters. The secondary stage with the water system (no one was hiding/omitting this) is then going big scale away from hardware with a lot more surface area to reject the heat using only single phase. If you refer to the often quoted 4kW simulator on the PCB size of only two postcards, then we are talking about 16 GPUs or high performing mining chips in 20nm or similar, each putting out 250W (simplified analogy). Try cooling this with heatsinks and air or single phase water cooling with water blocks requiring sufficient space to be mounted on - all introducing additional multiple thermal resistance layers (silicon to package to heatsink or water block to air or water). The amount of air (hurricane speeds?) or water flow required will be immense and/or the energy to cool down air/water will be as well higher.
On top of that, several manufacturers having employed water cooling blocks noticed that it's now actually the power components like buck regulators, etc. which contribute more and more heat with increasing currents required for the mining chips which still needs to be rejected (e.g. fans despite water cooling blocks). And there is no elegant way to mount a water block on those due to lack of sufficient co-planarity over different components' heights. With 2-phase immersion cooling, the fluid simply surrounds everything, even the side of the chip packing to cool it almost all around, no matter which shape. Again, multiple of the biggest mining hardware manufacturers are seriously considering immersion cooling. Why should they still do that if 2-phase immersion cooling doesn't make much sense according to you? So yes, maybe we should all simply sit back, relax and wait as 2112 mentioned: "Time will show".