Mercury Energy says it now treats all its customers as vulnerable in the wake of Folole Muliaga's death.
Former Mercury Energy manager James Moulder was giving evidence at the inquest at Auckland Coroner's Court into Mrs Muliaga's death on May 29 last year.
Mrs Muliaga, who was usingan oxygen machine, died in her Mangere home after a contractor cut her power because of an overdue bill of $168.40.
Mr Moulder said Mercury Energy admitted it did not comply with several guidelines for state-owned enterprises in relation to its treatment of vulnerable customers.
He said a call from Mrs Muliaga's husband on May 1 in which he said on four occasions that his wife was in hospital was not enough to flag at the time that she needed electricity for health reasons.
Mr Moulder agreed the processes for telling customers ways to identify themselves as vulnerable wasn't as good as it could have been, but that those processes had since been improved.
"We as a company and as industry, didn't comply with all the elements of the guidelines and for that we are very regretful," he said.
"We consider everybody to be vulnerable and we have worked hard to make sure that our systems are better than everyone in the industry because of this tragedy."
The contractor who cut the power to Mrs Muliaga is expected to give evidence later today. Name suppression has been continued for him.
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