EL DORADO HILLS (CBS13) – Jennifer and Paulo Borges are restocking their fridge after their lights went out late Friday afternoon in El Dorado Hills.

The outages were part of rolling blackouts called for by the California ISO as the electrical grid was under extra strain amid excessive heat.

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“I think it was just scary just the thought that it was day one and we were already losing power,” Jennifer Borges, who lost power during Friday’s rotating outage, said.

“And then the worry about losing food, freezers defrosting and you know the fridge,” Paulo Borges, Jennifer’s husband, said.

Another rotating outage came Saturday after Cal-ISO issued its latest stage 3 emergency. CBS13 learned this outage hit the Central Coast and Central Valley including San Joaquin county.

Those impacted by the blackouts were baffled.

“I don’t know if we got that information, like how, where do they decide?” Jennifer Borges said.

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CBS13 wanted to find out that information from both Cal ISO and PG&E. Cal ISO said they ask utility companies to reduce the load to keep the power grid reliable and stable.

“They then determine how that happens within their territory,” Vonette Fontaine, Cal ISO public information officer, said.

A spokesperson from PG&E told us that it gets those directives from Cal ISO. The agency tells the utility how much strain is being put on the grid then that determines where the outages will happen and how many customers will be impacted, according to PG&E.

The Borges family said they understand why this is happening. But as the temps rise, so do their concerns.

“Knowing that the heat is just going to get worse in the coming day, that is just the scariest thing,” Jennifer Borges said.

What’s even scarier is these power outages could be a matter of life or death.

“Then there’s those people that have oxygen machines. And some people need C-Paps; anybody that has medical devices that they need, you know, what are they doing?” Paulo Borges said.

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PG&E said it had restored a majority of the customers impacted by Saturday’s outage.