3 ms·

The Microsoft design of filling an airtight submersible structure with argon and dropping it to the bottom of the ocean floor is the alternative design - you’re

The Microsoft design of filling an airtight submersible structure with argon and dropping it to the bottom of the ocean floor is the alternative design - you’re not looking to do repairs but amortize the low cost of failures across the value you extract. The biggest issue with space is not repairability but heat - when you’re in a vacuum the only way to disperse heat is through black body radiation and that’s horribly slow compared with normal mechanisms. It means you need giant physical structures whose sole job is to accept heat from the processing core and radiate it away and have so much more material that you can radiate it at the speed you generate. It’s a huge unsolved physics problem which is why everyone is skeptical.

bakies 3mo ago
It's so, so cheap to buy tap water and dump it on the heat exchange.
- munk-a 3mo ago
  With well considered engineering it doesn't even need to be tap water. If you have a closed loop thermal conductor that interacts with the components themselves you can then use really trashy contaminated water that just needs to be clean enough not to actively erode the heat transfer mechanism. We have setups like this all the time that use condensed air via cooling towers or salt water immersed heat sinks to discharge energy - it's more expensive than tap water but it isn't technically complex. So if it ever becomes unpalatable (likely due to politics) to use tap water there are some readily available alternatives. The big win of being in space is just a worse alternative to using an intermediary heat transfer medium.
  - bakies 3mo ago
    It's the same reason we use single use plastics. No matter the politics the business decision is going to use the cheapest option available. I'm confident that all the hyperscalers could create datacenters that don't affect the local community basically in anyway. There's been data centers hidden in plain sight for decades. The demand drives it to the lowest common denominator
nkrisc 3mo ago
It’s not an unsolved physics problem. Every satellite in space has to deal with it and even the ISS deals with it by having massive radiator arrays that face perpendicular to the sun. The problem with data centers in space is one of materials science and engineering: how to make radiators large enough and effective enough to cool it while also being economically feasible, both in terms of construction and getting them up there in the first place. We can make a space data center right now. It would just be terrible and expensive.
- xienze 3mo ago
  I think it's not necessarily about being the cheapest option, but a more politically acceptable one. I don't think you're going to get people protesting a data center in space considering it won't be next to their house, won't use water, and won't lead to increased electricity rates. I could see companies paying a premium to keep the political heat associated with traditional data centers off their backs.
- kibwen 3mo ago
  The physics problem regarding radiator arrays isn't unsolved, but it's not a problem that scales up gracefully. Small-scale radiators could get by via passive cooling, but large-scale radiators need active cooling, and now you need fluid, pipes, and pumps that all represent additional launch mass and points of failure (and the pumps are generating heat of their own, so now you need more radiators...).
  - AnthonyMouse 3mo ago
    Doesn't active cooling provide counterbalancing options to improve efficiency though? For example, use multi-stage heat pumps with different refrigerants so that you can make the hot side very hot and thereby need less mass for radiators.
  - aeternum 3mo ago
    Thermal dissipation scales quartically with T, that's about as graceful as you can get from a physics POV, very few things scale at that rate. COTs GPUs throttle at about 90-100C but that's because they have plastic parts and solder that melts. Those are relatively easy to eliminate. We haven't tried much to scale up operating temp.
chris_money202 3mo ago
Right, a heat exchange is reusable though on earth and can be recycled across multiple SKUs and thus depreciates longer. In space similar to how you can’t repair you also can’t swap.

bakies 3mo ago

It's so, so cheap to buy tap water and dump it on the heat exchange.

munk-a 3mo ago
With well considered engineering it doesn't even need to be tap water. If you have a closed loop thermal conductor that interacts with the components themselves you can then use really trashy contaminated water that just needs to be clean enough not to actively erode the heat transfer mechanism. We have setups like this all the time that use condensed air via cooling towers or salt water immersed heat sinks to discharge energy - it's more expensive than tap water but it isn't technically complex. So if it ever becomes unpalatable (likely due to politics) to use tap water there are some readily available alternatives. The big win of being in space is just a worse alternative to using an intermediary heat transfer medium.
- bakies 3mo ago
  It's the same reason we use single use plastics. No matter the politics the business decision is going to use the cheapest option available. I'm confident that all the hyperscalers could create datacenters that don't affect the local community basically in anyway. There's been data centers hidden in plain sight for decades. The demand drives it to the lowest common denominator

nkrisc 3mo ago

It’s not an unsolved physics problem. Every satellite in space has to deal with it and even the ISS deals with it by having massive radiator arrays that face perpendicular to the sun. The problem with data centers in space is one of materials science and engineering: how to make radiators large enough and effective enough to cool it while also being economically feasible, both in terms of construction and getting them up there in the first place. We can make a space data center right now. It would just be terrible and expensive.

xienze 3mo ago
I think it's not necessarily about being the cheapest option, but a more politically acceptable one. I don't think you're going to get people protesting a data center in space considering it won't be next to their house, won't use water, and won't lead to increased electricity rates. I could see companies paying a premium to keep the political heat associated with traditional data centers off their backs.
kibwen 3mo ago
The physics problem regarding radiator arrays isn't unsolved, but it's not a problem that scales up gracefully. Small-scale radiators could get by via passive cooling, but large-scale radiators need active cooling, and now you need fluid, pipes, and pumps that all represent additional launch mass and points of failure (and the pumps are generating heat of their own, so now you need more radiators...).
- AnthonyMouse 3mo ago
  Doesn't active cooling provide counterbalancing options to improve efficiency though? For example, use multi-stage heat pumps with different refrigerants so that you can make the hot side very hot and thereby need less mass for radiators.
- aeternum 3mo ago
  Thermal dissipation scales quartically with T, that's about as graceful as you can get from a physics POV, very few things scale at that rate. COTs GPUs throttle at about 90-100C but that's because they have plastic parts and solder that melts. Those are relatively easy to eliminate. We haven't tried much to scale up operating temp.

chris_money202 3mo ago

Right, a heat exchange is reusable though on earth and can be recycled across multiple SKUs and thus depreciates longer. In space similar to how you can’t repair you also can’t swap.