Even though it’s been one week since San Diego experienced the biggest and most expensive blackout in its history, basic questions remain unanswered.
San Diego Gas & Electric executives said repeatedly that they had enough local power generation online at the time of the blackout when the Southwest Powerlink – one of two main transmission lines – went down. When the lights went out, the electricity demand in SDG&E’s region was for around 4,300 megawatts of power, enough to supply 4.3 million homes.
The other main transmission line along the I-5 corridor had the capacity to carry more than half of that demand. And San Diego’s three local power plants could have generated the remaining electricity demand, according to local energy engineer Bill Powers.
“The question is were we? Was that amount online when the blackout occurred?" Powers asked.
But SDG&E won’t say how much power was generated at the region’s three major power plants in Escondido, Carlsbad and Otay Mesa when the blackout occurred. The company instead referred the question to the California Independent System Operator (ISO), whose job it is to make sure there is enough electricity in the grid to serve needs. The ISO also refused to answer that question until its investigation is complete.
Powers said it makes little sense for SDG&E and the ISO not to release that basic information now.
“I think it is incumbent upon them to let the community know that this is how much generation we had and you can put to rest the concerns that there wasn’t sufficient local generation online to protect the grid for an incident like the loss of the Southwest Powerlink,” Powers said.
The ISO is one of three agencies which is investigating the outage last week that cut off power to five million people in Southern California.
