Whether they can be worth the money it cost to put them in orbit is another story.
Apples to oranges, long-lived satellites have modest power needs. Doing a back-of-the napkin math on required size of solar array and radiative elements for a single-rack's worth of energy is a sobering exercise for those who are a overly exuberant on the topic. The all-in power estimate for a single GB300 chip is 2.1kW
Edit: ISS is about 90KW steady state, and the collector to radiator area ratio is about 5:1. Dunno about the mass ratio.
My point is not that space data centers are viable or sensible. Only that the need for cooling is limited. If a terrestrial datacenter was powered only by its rooftop solar panels, cooling it would be trivial. Space is harder, but there just isn’t that much heat to dump.
A simple rock in orbit radiates exactly as much heat as hits it from the sun, on average.
You are correct that the first law of thermodynamics dictates the energy, but anyone who has parked a car in the sun will tell you, the temperature where the absorption/dissipation equilibrium is achieved is often incompatible with the survival of the cargo.
edit to your edit:
> Edit: ISS is about 90KW steady state, and the collector to radiator area ratio is about 5:1. Dunno about the mass ratio.
Cool; that's about half the wattage of one modern full-height Nvidia AI rack (172kW) - you need two ISSes to service just 1 rack; extrapolate that to a data center's worth of racks and see if the math is mathing. The ISS is about the size of a(n American) football field.
You won't immediately freeze if you enter space without a suit. You'll die almost immediately, but it will be because your blood will begin to boil because of the lack of pressure kinda like an extreme form of divers sickness - it's just not the cold that'll get you first.
FYI; that's not how it works, you and the rock you mentioned in an earlier comment cannot have the same temperature of -18C. This is due to differences in material, and geometry to a lesser extent.
Even if you were rock-shaped, the rates of energy absorption and radiation is what determines your remains' temperature, this ratio differs for different materials, and thus difference fiilnal temperatures.
The total available energy from the sun in LEO averages about 1.36KW/m^2, and more than this is radiated away by current deployed technology.
No, not just a bit. It varies by hundreds of degrees depending on the materials α/ε ratio.
Your mental model is off: materials that good absorbers but poor emitters will get very hot, and the flip-side stay cool, and are used to make the cooling elements in the ISS . The temperature of ball of black nickel at 1 AU will settle at balmy 239C - not -18C. Polished Aluminum -> roughly 145C.
My nickel guy is gonna be so disappointed.
I do understand the correction, so thank you. Doesn’t change my point at all, and I fear we are talking past each other so I’ll call it a day.
You know space rocks where we live don’t melt because the Earth and moon don’t melt.
Without gravity, it is likely that this can be done only by pumping continuously a lot of liquid, which will increase the power consumption and it will reduce reliability.
Solar panels that have heat radiators on their backside will have a higher temperature than simple solar panels, where half of the absorbed solar energy is converted into electrical energy and taken away. The efficiency of solar panels decreases with temperature, so hotter solar panels will have to be made bigger for the same electrical energy output.
Maintenance would be too expensive, so a space datacenter would have to be overprovisioned, e.g. with a double number of GPUs, to keep the average of the number of still working GPUs at the desired level over the lifetime of the datacenter. This will also increase the power and cooling requirements in the early part of a life cycle, and both the power generation and the cooling will have to be dimensioned for the maximum values, not for the average values.
It is certainly possible to design a datacenter that will work in space, but there is a very large number of difficulties that will increase the cost both in comparison with terrestrial datacenters and in comparison with existing satellites.
Until a detailed design is done by someone, it is not possible to know exactly how many times more expensive will be a space datacenter, but my opinion, as an engineer with experience in industrial design, is that the cost will be too high to make it worthwhile.