Substation failure triggers major blackout across Prague and northern Czechia
July 2025Published 15 Sept 2026Responsible editor: Chief Editor
- Where
- CEPS substation in Chodov, Prague and northern Czechia
- Operator
- CEPS
- What
- Substation failure caused major blackout
- Injuries
- None reported
- Cause
- Not reported
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Companies named in the reporting of this entry (being named is not a finding of fault): CEPS
What happened
A major power outage struck much of Prague shortly after noon local time on 4 July 2025, affecting the city centre and districts including Sporilov and Jizni Mesto. Prague Energy (PRE) confirmed the cause was a failure at the CEPS substation in Chodov. Northern regions including Usti nad Labem, Teplice, Liberec and Jablonec were also affected, with tram services in Liberec halted. The grid operator CEPS reported a loss of voltage across parts of the national grid, and energy analysts noted a sudden 30 percent drop in grid load.
In Prague, metro lines A, B and C and tram services stopped, mainly affecting the eastern, right-bank part of the city. Train services to nearby towns including Kolin, Benesov and Kutna Hora were disrupted, shops closed and ATMs went offline. Firefighters responded to numerous calls to free people trapped in lifts and reported smoke from buildings caused by emergency diesel generators. The underlying technical cause of the substation failure was not reported.
Contributing factors
A failure at the CEPS substation in Chodov caused a loss of voltage across parts of the national grid, with a reported sudden 30 percent drop in grid load. The specific equipment fault was not reported.
Lessons learned
- A substation failure at Chodov caused rapid voltage loss and a 30 percent grid load drop, so operators must model single point of failure effects on urban transport and retail.
- Emergency diesel generators started during the outage produced smoke in buildings, so operators should site and maintain them to limit secondary fire service calls.
- Lift entrapment followed the urban blackout, so building operators and emergency services need pre agreed release protocols.
More lessons on fire suppression and firefighting, outages, backup supply and restoration, from every incident on the register.
Not yet known
- Specific equipment fault at the substation
- Duration and cost of the blackout
- Age and model of substation equipment
This entry is updated when these are reported. Get an alert for the next one like it.
Source
Other entries that name Prague
Published 2026-09-15. Written from public reporting. Descriptive, not investigative. See the data accuracy disclaimer.
