THE DATA CENTRE

ACT 01 · THE HALL — walk it at real scale

This is a data-centre hall drawn at real size: one floor tile is 600 mm, a rack is 600 mm wide and 1.2 m deep, the aisles are two tiles wide, and the figure in the cold aisle is 1.75 m tall. Racks stand in pairs of rows, back to back: their fronts face a cold aisle where chilled air comes up through perforated tiles, and their backs face a hot aisle closed in with doors at the ends and glass up to the ceiling. Four rows hold 48 ordinary racks; the two rows at the back hold twelve AI racks with their own coolant loop. Press WALK and scrub the slider to walk the aisles at eye height.

What runs on these machines, and how work is placed on them: The Cluster. How the machines agree with each other when some fail: The Machine Room.

FACT Rack unit 1U = 1.75 in = 44.45 mm; 19-inch panel width (EIA-310).
FACT Hot-aisle/cold-aisle layout and containment as in ASHRAE TC 9.9 and The Green Grid guidance.
MODEL The hall is invented; sizes are real, the site is not.

sources

EIA-310-D (ANSI/EIA), Cabinets, Racks, Panels and Associated Equipment — 19-inch width, 1U = 1.75 in.
ASHRAE TC 9.9, Thermal Guidelines for Data Processing Environments (5th ed., 2021) — recommended inlet 18–27 °C.
Uptime Institute Global Data Center Survey 2024 (keynote report 146) — average rack density below 8 kW.
Uptime Institute Global Data Center Survey 2024 and 2025 — average PUE 1.56 (2024) and about 1.54 (2025), flat for six years; Uptime Intelligence update 420 (Oct 2025).
Google, Data center efficiency (datacenters.google/efficiency) — 2024 fleet PUE 1.09 trailing twelve months.
The Green Grid, PUE and WUE white papers (WP #49, 2012; WP #35, 2011); ISO/IEC 30134-2:2016 (PUE) and 30134-9 (WUE).
NVIDIA GB200 NVL72 product page; Supermicro SRS-GB200-NVL72 and Gigabyte GIGAPOD spec sheets (up to 130–132 kW); SemiAnalysis, GB200 hardware architecture (2024) — ~120 kW per rack.
NFPA 110, Standard for Emergency and Standby Power Systems — Type 10: power restored within 10 s.
Shehabi A. et al., 2024 United States Data Center Energy Usage Report, LBNL-2001637 — US data centres 4.4 % of US electricity in 2023; equipment efficiencies.
Shehabi A. et al., United States Data Center Energy Usage Report, LBNL-1005775 (2016) — ~1.8 L/kWh on site, ~7.6 L/kWh at generation.
Hölzle U., Powering a Google search, Official Google Blog, 11 Jan 2009 — 0.0003 kWh per search.
Elsworth C. et al. (Google), Measuring the environmental impact of delivering AI at Google scale, Aug 2025 — median Gemini Apps text prompt 0.24 Wh, 0.26 mL water (May 2025).
You J., How much energy does ChatGPT use?, Epoch AI, Feb 2025 — ~0.3 Wh for a typical GPT-4o query.
Altman S., The Gentle Singularity, June 2025 — average ChatGPT query ~0.34 Wh.
de Vries A., The growing energy footprint of artificial intelligence, Joule 7 (2023) — ~3 Wh per LLM interaction.
Kamiya G., The carbon footprint of streaming video: fact-checking the headlines, IEA, Dec 2020 — 0.077 kWh per hour (2019), devices 72 %, networks 23 %, data centres 5 %.
Microsoft, Sustainable by design: next-generation datacenters consume zero water for cooling, Dec 2024 — FY2024 WUE 0.30 L/kWh.
Orkustofnun (National Energy Authority of Iceland), electricity generation statistics 2023 — ~20.1 TWh: hydro ~14.1 TWh, geothermal ~6.0 TWh.
Data Center Knowledge, Free cooling in Iceland: a closer look at the Verne Global data center (2013); EE Power, Icelandic location helps data center achieve PUE of 1.21 (2014).
Icelandic Met Office (Veðurstofa Íslands), climate normals — Keflavík annual mean about 5 °C.
IEA, Energy and AI (2025) — data centres used about 415 TWh in 2024, about 1.5 % of world electricity.

The hall, its layout and its equipment are invented and drawn by this page at real dimensions; no real facility is shown. Per-action energy figures are estimates from the studies named, not measurements of any one service.