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Want an energy efficient datacenter? Build it underwater

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141–150 of 172 posts

Re: Want an energy efficient datacenter? Build it underwater

#141

Earlier quoted context omitted.

I don't think it would be that complex, since the pods can be permanently sealed and don't need to exchange matter with the environment. I would assume that a lot of the complexity in waterproofing marine vessels comes from the need for openable doors.

No doubt doors are one of the biggest challenges. Many of the challenges could be reduced or mitigated if the pods could be at least partially pressurized to reduce the pressure differential between the inside and out -- but that introduces another complexity -- can the server hardware handle it. There are quite a few engineering challenges, none of them unsolvable but also none of them seem necessary when it seems t…

Hosting companies would be either adding capacity (new locations, new land, new construction) or filling existing capacity. Once capacity is full at a location, then what?

The marginal, incremental value of adding a single server once capacity is reached is currently quite high. Using bogus numbers, lets say a location can hold 100,000 servers, then the marginal cost to add the 100,001st server will be very high, and might cost millions. These costs include:

- Cost of planning - when? Which countries? Which locations? Do you serve Kenya out of say South Africa? Or do you need to go to the mountains of Kenya where the air is a more consistent temperature?

- Cost of finding locations - doing deals to get the land for server farms is likely costly.

- Actually buying/leasing the land - how in advance do you do this? Years? Months? Weeks? Leasing land that lays dormant for say 18 months is wasted money.

- Getting approval to put in the required infrastructure (data cables, electricity, redundancy etc)

- Engineering/architectural costs to design buildings each and every time for varying sizes, in different regulatory environments.

- Cost of construction.

- Wasted capacity. There may be a need worldwide for say 50,000 servers, but with multiple continents, that may equate to several locations with 100,000 capacity.

All those costs add up.

Compare that to the marginal cost is adding a standard pod, with a lower server numbers per pod, mass manufactured in one location and shipped to a regulation free spot in the ocean. The marginal cost is not millions to go from (bogus numbers of) 100,000 to 100,001, it is the cost of one additional pod, at a much lower number, e.g. to go from 10,000 to 10,001 costs a fraction of the 100,000 to 100,001 example. The waste is also reduced, as multiple countries/continents can have say an additional X% capacity, added in smaller increments, rather than huge leaps in (initially) wasted capacity.

Now, is that overall cheaper? Maybe, maybe not, who knows? But many large hosting businesses might prefer say a 10% increase in theoretical cost per server added in smaller discrete numbers of servers. Factor in adding capacity in smaller increments with less capacity waste, less need to acquire the rights to land in advance and it might be cheaper in aggregate, even if it is theoretically more expensive per server at currently active locations.

Incidentally, that is the core value proposition of cloud computing like AWS - that you can add capacity incrementally. Despite there being theoretically cheaper options running your own hardware, this is larger capital outlay, with longer turnarounds to add capacity.

Re: Want an energy efficient datacenter? Build it underwater

#142
post #126
post #70

Earlier quoted context omitted.

Nuclear power plants usually dump their tertiary cooling water into the ocean. That's not a great situation for the local sea life (within a few hundred meters, IIRC), but doesn't have much significance beyond that. That is several orders of magnitudes more heat output than could conceivably come off a data centre. So their dismissiveness is likely warranted. A bit more concerning is the notion of relocating these da…

Nuclear power plants usually dump their tertiary cooling water into the ocean. Nuclear plants also use cooling towers to lower the temperature before it dumped back into a lake/river/ocean. You can do a Google search, but those towers are hollow on the inside. Water runs down the inside walls and convection currents move up.

Yes, but not always. When the body of water is big enough, they don't need cooling towers.

Re: Want an energy efficient datacenter? Build it underwater

#143
post #5

This is great. A long time ago I had this crazy idea that if we built data centers at the poles, we could solve a lot of problems. Each one would sit idle 1/2 the year, but you could power it with solar and cool it with the outside air. Of course the big problem was latency. It was one I couldn't conceive of a good solution for. This is much better. It takes advantage of the same idea but you can park it right next t…

The poles are too cold. The datacenter maintained by researchers in Antarctica ends up having to be insulated against external temperatures, and then ironically has a worse cooling problem than ones on other continents.

Re: Want an energy efficient datacenter? Build it underwater

#145
post #100

Earlier quoted context omitted.

The sun provides over 1GW/sq km when it's shining. The biology seems to get by fine with that.

> The sun provides over 1GW/sq km when it's shining. The biology seems to get by fine with that. The issue is the amount of heat relative to the environment in which flora and fauna have evolved to survive, not relative to absolute zero. It's like saying that a 313 Kelvin body temperature shouldn't bother me because I do fine with 310K (~37C). It's only a 3K difference, after all.

OTOH, that 1GW drops to almost zero at night.

Re: Want an energy efficient datacenter? Build it underwater

#146

I really can't see the benefit of submerging these -- the complexity involved with keeping out several hundred PSI of sea water just doesn't seem to make sense to me. For the cooling aspect, they're already using pumped water and heat exchangers. What is the benefit of submersion vs just pumping sea water from a pipe to a land, or barge-based datacenter and using that to cool?

>the complexity involved with keeping out several hundred PSI of sea water just doesn't seem to make sense to me.

Use immersed electronics.

ROVs and the like have quite complicated onboard control systems. They're immersed in mineral oil (or something like that). They don't get wet and hydrostatic pressure is no longer an issue.

Re: Want an energy efficient datacenter? Build it underwater

#147
post #27
post #18

Always fun with people that run with exotic ideas =) I might be missing some aspects but would it not be much easier to locate the datacenter on land but close to the ocean (or other large body of water), with similar principles as used for cooling nuclear reactors? Then you would get the benefits but would not have the same strict requirements on reliability of the components. If you locate it on land you would also…

I would be concerned with the cost of real estate at that point. They didn't talk about it, but I expect they're not paying rent/buying land off shore. Seaside real estate is expensive afaik.

>They didn't talk about it, but I expect they're not paying rent/buying land off shore. Seaside real estate is expensive afaik.

I don't know how it'd work for something like a submerged data center, but blocks of area are indeed sold off by the government bodies that administrate them to O&G producers. This is also not cheap.

Re: Want an energy efficient datacenter? Build it underwater

#148

I'm all for exploring new approaches, however: a) Salt water is highly corrosive. Wouldn't maintenance costs be high? b) Isn't marine biology highly sensitive to heat pollution? For high latency services like Amazon Glacier, wouldn't it make sense to host in a place like Iceland? Really cheap hydrothermic/clean power. Highly educated local talent pool, and relatively consistent cool temperatures. If you're maintainin…

Essentially, I think it makes sense to get better at solar than to have Steve Zissou as a server admin. 1) In the original article, these server farms would be remote administration only. 2) Such facilities would make the secret construction of one's James Bond Villain underwater base much, much easier. (Wouldn't Elon Musk, Jeff Bezos, and Peter Thiel all make great Bond villains?)

Kim DotCom needs a good place that is in international waters so he doesn't get extradited.

Villains are sometimes just victims of their circumstances and trying to survive.

Elon and co are the secret villains.

Re: Want an energy efficient datacenter? Build it underwater

#149
post #95

Earlier quoted context omitted.

This sounds really interesting, can you explain it further for a layman? (Not being snarky, I genuinely know very little about chemistry)

It's fairly common on boats to have exposed zinc whose only purpose is to be sacrificially electrolized (IIRC) to protect your steel or aluminum.

I worked on a 120m old passenger ship for a while. During dry-dock each year we'd put 8 or so 2kg (ish) zinc anodes around the hull, a welded bracket around each one.

The trouble was that they're pretty expensive, and zinc has a great resale value - so we had to do extra watches around the lower decks with rigged firehoses to try and stop local divers stealing them who knew we'd just come out of drydock. (This was in the Philippines). We lost several that way.

Re: Want an energy efficient datacenter? Build it underwater

#150
post #116

Earlier quoted context omitted.

I will say that my only experience with sacrificial anodes is that they help but don't prevent corrosion entirely. We had screws starting to turn to dust from a couple hundred hours of pool water exposure even with a sizeable anode. Maybe it wasn't in sufficient contact or whatever. They're unlikely to be curealls anyway.

One thing about sacrificial anodes is that multiple seem to be required. E.g. even though the hull of a ship may be a good conductor, you don't just have one sacrificial anode. Wikipedia ["Galvanic anode"]: The arrangement of the anodes is then planned so as to provide an even distribution of current over the whole structure. For example, if a particular design shows that a pipeline 10 kilometres (6.2 mi) long needs…

I came here to say the exact same thing. The resistance of the metal surface will mean you want to cover the metal needing protection all around. I think dependant on the salinity of the water different metals should be tested to best suit you environment.
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