Power utility Eskom on Wednesday called on consumers to switch off geysers, pool pumps and all non-e.
Klitschko knows he doesn't need a rematch, "but my ego, something deep inside, tells me quite clearly that I still need to give this man real punishment," he told Die Welt newspaper on Tuesday.
"I want to knock him out in the ring. This account is still open," he said.
However, Klitschko's manager Bernd Boente has ruled out a rematch.
Klitschko beat Chisora on points in Munich on Saturday night, but the win was overshadowed by the challenger's conduct outside of the ring.
It culminated in a post-fight brawl with former WBA champion David Haye, for which the 28-year-old has apologised.
Chisora alos slapped Klitschko at their weigh-in on Friday, and spat water in younger brother Wladimir's face before the bout.
"Before the fight I still thought that how he was presenting himself, how he behaved, was a show. But then I realised he wasn't acting. He must be crazy."
German police want to speak to Haye about the incident but may have to wait as he posted a picture of himself on Twitter in a first-class aeroplane seat on Tuesday, reportedly on his way to Las Vegas. "Jetting off to warmer climates. Its PARTY TIME!" Haye tweeted.
The WBC fined Chisora $50000 for the slap, and Klitschko said any further punishment "has to really hurt. It can't be that this lout drags the sport of boxing into such disrepute."
At 40, Klitschko said he had no immediate plans to retire. - Sapa-AP