Power utility Eskom on Wednesday called on consumers to switch off geysers, pool pumps and all non-e.
This happened just moments before she was impaled and seriously injured.
Chantal Beyer, 24, who is in the intensive care unit of the Krugersdorp Private Clinic, told her uncle, Thom Peeters, that game park owner Alex Richter had snapped pictures of her just seconds before the accident, and that he had suggested she should "stand just a little bit closer".
Peeters said the rhino's horn had penetrated Beyers' chest from behind, on the right, almost exiting through her shoulder and resulting in a collapsed lung and broken ribs.
She was on a game drive with nine other people at the Aloe Ridge hotel and nature reserve in Muldersdrift when Richter stopped near two rhinos.
He reportedly used chunks of mieliepap to coax the rhinos towards them, then told his guests they could get out of the car to take pictures, as it was completely safe.
Richter declined to comment, then got into his car and drove away.