New report shows what caused San Francisco's blackout in December

A new report from Exponent has identified the cause of the widespread power outage that affected 120,000 PG&E customers in San Francisco on December 20.

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Vinita Duniphin Briefs Source report

What happened

According to ABC7 Bay Area’s source item, New report shows what caused San Francisco’s blackout in December, A new report from Exponent has identified the cause of the widespread power outage that affected 120,000 PG&E customers in San Francisco on December 20.

Context

The development sits in VINI’s Bay Area file for local readers tracking public services, civic decisions, transportation, housing, safety, and community life across the Bay Area. The original report is linked so readers can check the source account, follow later updates, and compare new coverage against the first published record. The source item is dated 2026-05-09T06:35:54+00:00.

What to watch

Open questions include whether primary sources issue follow-up statements, whether local or market impacts become clearer, and whether additional reporting changes the timeline or adds material context.

Source

Primary source: New report shows what caused San Francisco’s blackout in December via ABC7 Bay Area. VINI cites and links the source; it does not reproduce the publisher’s full article text without rights clearance.

This source-cited VINI report links to the original publisher record. VINI does not republish third-party article bodies without rights clearance. 1 source listed.

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