SA can't take another blackout: Joyce

South Australia's economy cannot afford another statewide blackout because it would destroy business confidence, Deputy Prime Minister Barnaby Joyce says.

"I know as an accountant that we can't have another event like we did the other day with the blackout," Mr Joyce told reporters in Adelaide on Friday.

"Businesses will completely lose confidence in wanting to set up here and that would be an incredibly bad outcome for South Australia."