San Francisco, Saturday, December 20, 2025: the blackout replayed on the real city from 911 dispatch, grid-outage and building data, then rewound by an event-driven world model. Read the essay.
Click any incident after 1:09 pm in a restored battalion to trace its chain, from the committed logs.
Restoration variants ranked by incidents avoided (mean of three runs) per 1,000 customer-hours restored early: a cost proxy, not a dollar cost.
Power outages are known to raise the risk of elevator entrapments, and restoring power sooner generally reduces emergency calls. No numbers, no specific incidents: general knowledge, not this event.
This incident’s exact chain back to the failure, and a ranked, tested set of fixes, from the committed logs of a model that watched this city.
Pick a hypothesis and its settings. The world model runs it now, on this server, and the page draws each event as it is committed. A request someone has already run replays from the cache.
Saturday, December 20, 2025: a fire at PG&E’s Mission substation (1:09 pm) leaves about 130,000 customers, roughly 30% of the city, dark within two hours. The city is Google’s photorealistic 3D San Francisco, and each of 168,674 LiDAR-measured building footprints is tinted by its power state. Drag the divider: real 911 dispatch on the left, the event-driven world model’s own rollout on the right, from 12:55 pm onward. The model was trained only on data from before May 2025 and given only the real grid, weather and calendar. Its incident locations are drawn from past incidents of the same battalion and class, not measured. Its unit trails are its own dispatches, station to incident in a straight line, timed from assignment to release in its service log: inferred routing, real timing.
A rewind reconstructs what was knowable at the chosen moment from the record, changes one thing, and replays the rest as a possible world: everything outside the change’s reach stays identical, and what differs is the model’s claim, relative to what it has learned. Here, restore power at 3 pm, using the real per-battalion restoration data. Incidents identical to the unchanged world stay grey. Incidents the restoration prevents appear as violet rings, larger for elevator rescues, and that is the dominant effect. A few incidents appear only in the restored world, in magenta: the learned response isn’t the same in every class, so restoring power doesn’t reduce every incident type everywhere. Buildings in the served battalions relight as the model’s own outage input falls. The second what-if adds one engine at Station 1 from 1 pm and follows the change as it spreads from station to station over three days. Or pose your own below the map.
Click any incident after the fire in a restored battalion (rings mark the class these logs show restoration preventing most) to trace its chain back through the committed logs: the outage input, the model’s own rate for that class there, the shared draw that accepted it, and a but-for test against the restored world. It is exact with respect to the learned model. “Cheapest fix?” ranks real restoration variants by incidents avoided per customer-hour restored early, both counted over the same window.
City: Google Photorealistic 3D Tiles, graded to night on this page. Buildings: DataSF’s 177,023 LiDAR-derived building footprints (ynuv-fyni), simplified (Douglas-Peucker, slivers under 15 m² dropped) to 168,674; each is a volume from its measured ground to its measured roof peak that tints the photoreal mesh inside it. Neighborhoods: DataSF’s 41 Analysis Neighborhoods (j2bu-swwd). SFFD Fire Department Calls for Service: DataSF, Dec 16–23, 2025 unit-level rows, for incidents, fleet gauges and every engine, truck and medic trip, routed on DataSF’s street centerlines (3psu-pn9h). EAGLE-I San Francisco County customers out: Oak Ridge National Laboratory, 15-minute resolution, CC BY 4.0, shifted from UTC to Pacific time. Fire stations (DataSF, wt27-4jim) and ED hospitals (OpenStreetMap, emergency=yes) locate trip origins and destinations. Mission Substation: 66 8th St (OSM way 35115839; PG&E), fire at about 1:09 pm. High-voltage lines: HIFLD Electric Power Transmission Lines, clipped to SF.
Inferred, and labeled as such:
The ~30% figure is PG&E’s own; no share of the city is computed from EAGLE-I’s modeled customer total.
Everything marked “World model output” is read from the event-driven San Francisco world model’s committed logs: five runs, each with and without the intervention, warm-started on real history through 12:55 pm Dec 20 and generated by the model alone from there. Only model-generated incidents are counted; replayed history is excluded everywhere. Each beat’s own notes sit with its text above.