CNFL work crews making repairs to homes, adjacent to the substation, affected by the explosion Wednesday night. Alonso Tenorio / La Nacion

Q COSTA RICA  – The explosion and fire that knocked out of service the El Porvenir (Desamparados) electrical substation on Wednesday affected the daily lives of some 500,000 in the Greater Metropolitan Area (GAM) says the Compañía Nacional de Fuerza y Luz (CNFL) – National Power and Light Company.

The 7:00 pm explosion plunged 121,200 CFNL customers that is the equivalent of about 500,000 people who depend daily on the electrical service from the substation.

Although the CNFL was able to restore power to 85% of the population by the early hours of Thursday morning, it wasn’t until 6:00 pm, almost 24 hours, for some 4,500 customers before the lights were back on.

Infograph by La Nacion

Uncharged cellular phones, food spoiling in refrigerators, hot water showers and closed streets were some of the difficulties faced by many while work crews worked to restore service.

On Thursday, officials of the CNFL ruled out the report that the sparks from one of the light posts near the station caused the event. Some residents told the media that they had called the CNFL to report the “averia” (fault) and that it remained unattended. However, the CNFL says it did make the repair ours ahead of the explosion.

The State power and light company also defended accusations of poor maintenance and outdated equipment as the cause.

Luis Fernando Andrés, director Distribution at the CNFL, emphasized that the failed interruptor, a sort of giant breaker switch, had been inspected in February last. Andres added that the fire is something unusual, in his 30 years of work at the CNFL he had never seen something like it.

The Director assumes that it could have been an overvoltage in a interruptor with a capacity of supporting 34,500 volts, in that there may have been an overload that destroyed an adjacent circuit, that resulted in equipment failure, and the oil used in the equipment catching fire and exploding.

In the social media, some who live close to the substation, some literally next door, complained of the anomalies such as the contractors taking shortcuts and municipal officials turning a blind eye, that occurred in the 1970s when the plant was originally built.

And despite the statements by the CNFL, many of the comments revolve around the ‘sparking post’ and conclude that the lack of attention by the CNFL, despite the assurances to the contrary, was the principal cause of the emergency.

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