When Lynne Harris could see the flames of the Port Lincoln bushfire out of the window of her family home, she feared her worst nightmare was coming true. 

"Leaving in a bushfire isn't an option for us," Ms Harris said.

At about 1pm on Thursday, Lynne's husband Michael received a phone call alerting them to a fire in their bottom paddock. 

As Michael ran out the door to investigate with his ear still to the phone, Lynne immediately called triple-0.

"I was terrified, really terrified," Ms Harris said.

"But not only that, I couldn't go outside. I had to stay within buzzer range if he needed me. 

"I was really scared. I was really worried that the power was going to go out and my son would lose the ability to keep himself cool or to have the air filtered, which I knew would exacerbate all of his conditions and make everything much worse. We didn't have a plan B." 

Ms Harris said she watched large trees on their property go up in flames, as hot and blustery winds pushed the fire within 10 metres of their home. 

Fortunately, fire crews arrived quickly and were able to save the house. 

"We were really fortunate that it all came together, that the planes arrived, the firies arrived, the guys in bulldozers arrived and helicopters. It was all happening, really, really quickly," she said. 

"It was almost like hallelujah, the calvary had come. 

Ms Harris's Dan has severe myalgic encephalomyelitis, which is also known as chronic fatigue syndrome. 

"It's a really benign-sounding name for a horrendously debilitating condition," she said.

In the coming days, Ms Harris said, Dan was expected to suffer from "post-exertional malaise" due to all of the noise and smell from the fire, which would exacerbate his symptoms. 

"He will be really, really unwell and his functional baseline will be even lower," she said. 

The last time a fire threatened their home was in 2009, but Ms Harris said back then it was easier for them to leave. 

"A house is a house," she said. "We've got insurance. Everything could be replaced. 

"We would just take the dog and the important documents and go, but that wasn't an option this time, not an option at all, so having to stay was really scary."

Ms Harris said more funding was needed to research her son's condition.

"So people like us aren't put in this position and putting other people — emergency services — in [that] position. You know, it's their lives at stake," she said. 

SA Power Networks launches investigation

On Friday, the Country Fire Service confirmed a power infrastructure failure started the bushfire within 80 to 100 metres of the first property. 

In a statement, SA Power Networks said "it is aware that a power outage occurred about the same time as the Port Lincoln fire got underway". 

"We are conducting our own investigation and will cooperate fully with the Office of the Technical Regulator and other authorities investigating this incident."

One home and 15 industrial structures were destroyed in the blaze, which burned through more than 140 hectares. 

Earlier today, Minister for Emergency Services Joe Szakacs said "it was far too early" to comment on whether affected property owners would be compensated. 

"I haven't been fully briefed and we don't have the full cause analysis from the actual ignition point," he said. 

Mr Szakacs praised fire crews for their work to protect so many homes, especially given the close proximity of the ignition point to houses. 

"This was a really close call," he said. 

"It's a great save by our firefighters and they have absolutely saved lives and properties."

He said the fire was expected to continue to burn in the city's dump for a number of days.

"With hotter weather coming again in a few days' time, there are amplified efforts by our agencies to contain and suppress the fire that continues in the dump and continue to monitor hotspots," Mr Szakacs said.