David Ngwenya, who has been charged with the murder of Eskom employee Thembisile Yende, will on Wednesday appear in the Springs Magistrate's Court.
Ngwenya, a 43-year-old technician at Eskom, is accused of injecting his lover, Yende, with a substance before striking her on the head with a crowbar and subsequently suffocating and strangling her after a struggle in May.
He allegedly killed Yende after he suspected that she would "spill the beans" on his alleged involvement in a copper cable theft syndicate.
Yende, a 29-year-old mother of one, went missing on May 17.
Her body was found in an office at the isolated Eskom Pietersboth substation in Springs, Ekurhuleni, after Eskom workers detected a putrid smell more a week after she was reported missing.
At Ngwenya's last court appearance in September, his lawyer, Advocate Zola Majavu, said DNA results would exonerate his client.
"Most critically we are awaiting the outcome of the DNA evidence. I don't want to jinx it but depending on what the outcome is, I have reason to believe that based on my instructions the piece of DNA evidence will exonerate him," Majavu said.
Majavu said he would approach the court for a new bail application if the DNA results proved Ngwenya's innocence.