Most residents at Oak Knoll Villa are elderly, sick or disabled, so a loss of power means they're stranded and, for those on oxygen tanks, its a risk to their lives.

Adela Garcia lives at Oak Knoll where she and dozens of other elderly people sat for nearly 10 hours in the dark on Wednesday evening.

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"Some have cancer, heart problems, oxygen, and there's a lot of people that are sick," Garcia said. "They needed the help. I think that CPS should have helped us sooner than what they did."

However, CPS said that they too were in the dark about the living conditions at Oak Knoll.

"Our crew went onto the internet to see where the complex was located and didn't see anything there that indicated that this was a senior citizen living complex," said Albert Cantu with CPS Energy.

CPS also said that they checked their system and found that none of customers effected by the outage were on life-sustaining equipment.

But Adela says that she can name several people who rely on oxygen tanks.

While CPS didn't say whether knowing this information would have led to a faster response time, they are encouraging customers to register for their critical care program. It informs them of customers who are on life-sustaining equipment. Otherwise, they said, they have no way of knowing.