Police said officers who responded to the call found the two people next to a burning transformer.
The man died at the scene and the woman was taken to a hospital.
Authorities said they believe the woman was burned when she grabbed her husband trying to save him.
"I just heard a loud explosion and a lady screaming," said Jose Carrasco, who was near the scene. "I saw her half burned and she was crying, asking for help."
Two children, a 3-year-old and 6-year-old, were found in a truck parked near the lot.
Police said they believe they are the couple's children. They were unharmed and taken into protective custody.