'Hotter than the sun': alleged copper thief in hospital

A would-be copper thief has been burnt by a flame ball "hotter than the sun" after cutting into a high voltage cable with a knife.

The 31-year-old man is in hospital with serious burns after he pierced the 11,000 volt line at a power substation west of Brisbane in Wednesday's early hours.

His knife melted instantly when it made contact, likely creating a fireball about two metres in diameter.

"It would have been hotter than the surface of the sun," an Ergon Energy spokesperson told AAP.

"The fact that someone hasn't lost their life is an absolute miracle."

Pictures supplied by Ergon Energy from its Toowoomba substation show what was left of the knife after it was found nearby.

"That knife has melted instantly ... imagine what it would have done to your skin," the spokesperson said.

"Anyone within that vicinity would have significant injuries."

Police began investigating a break and enter at the Newtown substation after officers were called to a nearby service station around 4.30am.

They were responding to reports a man arrived earlier at the service station with serious burns to his face and hands asking for help.

He was later located by police at Toowoomba Hospital, where he remains in a serious condition.

The man was burnt when he cut the wires around 3am, resulting in about 800 Ergon customers losing power in the area for a few hours.

"It is probably one of the most risky attempts of theft that we have seen," the Ergon spokesperson said.

The man risked his life for "very little scrap value" after Ergon replaced copper wires with aluminium at the substation.

Ergon has made a change in its wiring policy after a widespread rise in copper theft.

It spends $4.5 million a year repairing copper theft damage.

"People try and steal copper from the network but in this case it was aluminium so it has very little scrap value," the spokesperson said.

"Someone has risked their life for a couple of dollars worth of aluminium."