Orbiting Data Centres: Radiators as the Quiet Heat Sink

Cooling a data centre on Earth can consume 10–30% of its energy budget and requires vast water use; in space there is no air or water, so heat must be dumped as infrared radiation through massive radiator panels. Those radiators become the limiting factor for megawatt-scale data processing in orbit, complicated by solar heating and the need to keep panels large enough to reject heat yet feasible to launch. The European Space Agency has studied orbital data centres (ASCEND), a startup (Starcloud) has launched an AI satellite, and Google is exploring space-based designs, signaling a staged path: begin with small processor counts in orbit, increase power budgets, then deployable radiators, and finally scalable heat rejection—subject to whether radiators can scale without becoming prohibitively large given launch costs.