Circuit breaker explosion and oil fire disable Vining Substation in Powell, Wyoming
June 2019Published 20 Sept 2026Responsible editor: Chief Editor
- Where
- Vining Substation on North Ingalls Street in Powell, Wyoming
- Operator
- City of Powell
- What
- Circuit breaker exploded damaging oil filled regulators
- 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): City of Powell
What happened
On 29 June 2019 the Vining Substation on North Ingalls Street in Powell, Wyoming lost power at around 5am. On-call electricians from the City of Powell attended and, following standard procedure, switched a circuit breaker back on from a separate control building. The breaker exploded, damaging nearby oil-filled regulators used for cooling. The oil ignited, sending flames from the equipment. Workers called emergency services immediately. No one was hurt, and a City of Powell official noted that staff were kept at a safe distance because the breaker is operated from a building on the property rather than in front of the energised equipment.
The fault caused prolonged power outages across the city. Technicians examining power flow data found a fault across all three phases but could not pinpoint a cause. The substation equipment was reported to be about 30 years old and at the end of its design life. Power was restored using temporary, cobbled together repairs while parts for lasting repairs, with lead times of up to 46 weeks, were sourced. Initial repairs were expected to cost the City of Powell about 150,000 US dollars, and the City of Powell council approved emergency procurement and a contract for a mobile substation if needed.
Contributing factors
Ageing substation equipment reported to be around 30 years old and at the end of its design life. The root cause of the initial outage and of the breaker failure could not be determined, although data showed a fault across all three phases.
Lessons learned
- Circuit breakers switched back on from a separate control building keep staff clear of violent failure. Operators should check that all re energisation controls are remote from the equipment.
- Oil filled regulators near circuit breakers can ignite if the breaker fails. Insurers should require separation or fire barriers around such equipment.
- Substation equipment at the end of its design life needs prioritised replacement. Operators should review condition of all 30 year old plant.
More lessons on electrical protection and isolation, spacing, layout and fire spread, maintenance, inspection and ageing assets, from every incident on the register.
Not yet known
- Exact cause of the three phase fault
- Circuit breaker model
- Duration of the power outages
This entry is updated when these are reported. Get an alert for the next one like it.
Source
Published 2026-09-20. Written from public reporting. Descriptive, not investigative. See the data accuracy disclaimer.
