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Want an energy efficient datacenter? Build it underwater

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Re: Want an energy efficient datacenter? Build it underwater

#63
post #9

I wonder what the cost differential is (any given rack, not just an underwater one) for a system which is designed to NEVER be maintained by people over its service life (or duty). Hard drive goes bad? Board fails? Just push the load elsewhere and shut off power to it. No idea what sort of attrition rate these systems have. Sure, you might be at 50% capacity after 3 years, but that's just like lithium ion batteries.

Some of the big cloud providers (Google and I think Facebook) do exactly this in their DC's, when hardware dies they just leave it dead until enough has failed in that rack to make it worth swapping out the whole thing. When you have a 100,000 of anything electrical MTBF will hit you every day.

I'm guessing that someone has done an equation and shown that to be cost effective. Does that calculation apply when the cost of building the data centre and running it are considerably higher due to the location you built in?

Re: Want an energy efficient datacenter? Build it underwater

#64

Earlier quoted context omitted.

> Salt water is highly corrosive. To metals. Not so much to plastics. > Isn't marine biology highly sensitive to heat pollution? Isn't land-based biology highly sensitive to heat pollution?

> Isn't land-based biology highly sensitive to heat pollution? No, land-based organisms comparatively have a much, much higher tolerance to temperature swings. Water's high heat capacity and conductivity means that most marine environments have extremely stable temperature ranges (a few degrees one way or other), so most marine species are adapted to live in only that range, and quickly die otherwise. Tropical fish a…

Sunlight imparts about a kilowatt per square meter to the surface of the ocean at noon, I'm not exactly sure how to use that information, but it does seem relevant for bounding the problem.

Re: Want an energy efficient datacenter? Build it underwater

#65

Earlier quoted context omitted.

Same as on land?

Securing a datacenter from intruders on land doesn't require military-grade underwater sensor equipment and response techniques. Securing a datacenter from intruders underwater would.

To be fair, it's also a lot harder to penetrate an underwater datacenter so the risk of attack is likely much lower.

Re: Want an energy efficient datacenter? Build it underwater

#66
I'm surprised that they're so dismissive of heat pollution. Google's Finland data center, which is cooled by ocean water, has a holding tank used to cool the ocean water before pumping it back into the ocean[1] in order to prevent a similar problem. I would like to see additional research here rather than baselessly dismissing it.

[1]: https://www.youtube.com/watch?v=VChOEvKicQQ

Re: Want an energy efficient datacenter? Build it underwater

#67
post #23

Earlier quoted context omitted.

But what about global warming ? Wouldn't rising water levels be a big threat to such experiments ?

Let's say climate change gets absolutely horrific, and we see a 1m rise in sea levels over the course of a pod's 10 year lifespan. So your underwater datacenter pod, originally deployed 200m below the surface, is now at 201m. Somehow I don't think this would be an enormous problem.

A similar argument could be made for concerns over rising water temperatures as a result of climate change - what might be considered a dramatic rise to climate scientists and marine biologists would likely have little impact on a datacenter.

Re: Want an energy efficient datacenter? Build it underwater

#68
post #64

Earlier quoted context omitted.

> Isn't land-based biology highly sensitive to heat pollution? No, land-based organisms comparatively have a much, much higher tolerance to temperature swings. Water's high heat capacity and conductivity means that most marine environments have extremely stable temperature ranges (a few degrees one way or other), so most marine species are adapted to live in only that range, and quickly die otherwise. Tropical fish a…

Sunlight imparts about a kilowatt per square meter to the surface of the ocean at noon, I'm not exactly sure how to use that information, but it does seem relevant for bounding the problem.

The specific heat of water is much higher than that of air.

Re: Want an energy efficient datacenter? Build it underwater

#70

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…

> b) Isn't marine biology highly sensitive to heat pollution? Impact on the marine environment is briefly mentioned in the last couple of paragraphs of the article, although they're a little dismissive and don't provide any evidence supporting their claim of negligible impact.

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 data centre pods. Long-term "reefs" that are relocated around the world could perhaps be a new and different vector for transmitting invasive organisms. I'm not an expert, but I'd want to hear a few of them opine as to whether this creates any risks that ordinary shipping does not.

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