The Physical Cloud

Episode 5, layer 5: Cooling

Cooling

Almost every watt that goes into a server comes out as heat. This episode follows that heat from the servers, into the air, into the water and finally outside.

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TPC is a fictional campus, rendered in Unreal Engine 5. Some 3D assets are made with the help of AI tools, and the narration uses an AI clone of Rick's own voice.

Layer 5 of 8: Cooling

1 Perimeter2 Entrance3 Operations4 Power5 Cooling6 Fire and life safety7 Connections8 Data halls

In this episode

How TPC keeps the cold air and the hot air apart, in two different hall layouts. How the room cooling units, called CRAHs, pass the heat into chilled water. TPC's shared water ring, built in sections with valves. How a heat exchanger hands the heat to a separate outdoor loop, and how the chillers and free cooling send it into the open air. Why cooling needs backup power too, and what happens when one room unit fails.

Three things to take away

  • The heat doesn't disappear. It moves on: from the servers to the air, to the water, and outside.
  • Keep the cold and the hot apart.
  • Cooling needs power too: at TPC, the fans, pumps and controls have their own UPS.

Who works here

  • Refrigeration and air-conditioning techniciansThey install, look after and repair the cooling plant: the room cooling units, the chillers and the equipment that carries the heat outside.
  • Controls techniciansThey look after the system that monitors and controls the building's equipment, so pumps, fans and cooling units respond the way they should.
  • ElectriciansThey install and maintain the electrical supplies and lighting that every camera, reader and gate motor depends on, and much more as the series moves inside.

The Careers Guide shows how people get into each job.

Sources

Each source is listed with the claim it supports.