Shane Daye, who was 27, was an instrumentation technician and had worked for Suncor for seven years.
Daye, who was born and raised in Fort McMurray, was killed on Sunday while working near electrical panels on the site.
An official cause of death has not been released.
Suncor has said Daye was severely injured and was pronounced dead in hospital.
The family says he was "an incredibly positive young man."
"Shane was ... (an) outgoing force in the lives of our family and his many friends," his sister, Christie Daye, said in a statement Wednesday.
"We will miss his smile and his energy. We will miss him bounding up the stairs and lighting up a room," she said.
"He loved hanging out with his friends and he was a great athlete, playing hockey, baseball and golf. He had a great sense of humour."
Alberta occupational health and safety officers are investigating Daye's death. Investigators have issued a stop-use order for the electrical panels as they try to determine what happened.
It is the second death of a Suncor employee at the worksite this year. In January, tailings operator Jerry Cooper's body was found submerged in a sand dump.