Could data centres ever be built in orbit?

Mint

20 hours ago

WHERE IS THE best place to build a data centre? Not on Earth at all, but in orbit, claims Philip Johnston, chief executive of Starcloud. The cost of launching things into space is falling fast, and once it has fallen far enough 'It's completely inevitable that all data centres will go into space,' he says.
An orbiting data centre, in a dawn-dusk sun-synchronous polar orbit that keeps it in continuous sunlight, could harness abundant solar energy. (With no atmosphere or clouds to scatter or block the Sun's rays, a given solar array generates five times as much energy in orbit as it would on Earth.) The frigid vacuum of space should make cooling easier, too, because cooling systems are more efficient when the ambient temperature is lower. SpaceX's Starlink and other satellite-internet constellations can provide fast connectivity with the ground. Computing clusters could be arranged in three dimensions, rather than two as on Earth, to speed up data transfer.
Starcloud, founded in January 2024, hopes to put all this into practice. This summer it is due to launch Starcloud 1, a fridge-size demonstrator satellite containing AI chips made by Nvidia, powered by a solar array with capacity of around a kilowatt (kW). These chips will have 100 times more processing power than any put into space before, says Ezra Feilden, Starcloud's technology chief.
The main aims of Starcloud 1 are to test radiation shielding and fault-diagnosis systems for the computer hardware, and to evaluate cooling techniques. A second satellite, Starcloud 2, is planned for the end of 2026, with 100 times more solar capacity and 100 times the computing power. The first commercial Starcloud satellite, with a 1MW solar array, would follow, with the aim of launching 40MW, shipping-container-size orbital data centres by the early 2030s. Several of these could then be stacked up and powered by an enormous solar array, measuring 4km by 4km, delivering 5GW of power.
There is no doubting Starcloud's ambition. But sceptics say its numbers do not add up. One analysis by Data Centre Dynamics, an industry publication, argues that Starcloud has overlooked the protective shielding solar panels need in orbit, overestimated solar power output and ignored the problem of collision avoidance.
Mr Johnston disagrees. For one thing, he notes, the satellites used in internet constellations rely on ordinary terrestrial solar panels and need only a thin layer of glass for shielding at that altitude (Starcloud would operate in a similar, but slightly higher, low-Earth orbit). He also points to an independent report on the prospects for orbiting data centres published in October by Thales, a French aerospace group. It reached strikingly similar conclusions to Starcloud's on power generation, thermal regulation and orbital control. Google and other American tech giants are also thought to be looking at the idea.
Everything hinges on launch costs. If they fall far enough, the cost of sending a data centre into space could be more than offset by availability of abundant, cheap solar energy. Starcloud expects reusable, heavy-lift rockets such as SpaceX's Starship to cut launch costs by more than 99% within a few years. And unlike space hotels or space factories, which require physical things to be carried up and down, data centres require only weightless bits to be sent to and from orbit. 'The first thing you would do, if there's low-cost launch,' says Mr Johnston, 'is build very large data centres in space.'
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