Residents in parts of far western New South Wales will have their power cut off for six hours on Sunday night and again late on Wednesday, after transmission towers were knocked down during wild weather described by the bureau as a "possible tornado".

About 10,000 homes and businesses in Broken Hill and surrounding areas lost supply when a wild storm swept through the region on Wednesday night.

The NSW government said a large back-up generator had since restored power to the area, but "planned outages are needed to maintain the performance of the generator".

It said electricity supply would be cut off between 11pm ACDT on Sunday and 5am the following morning to allow for maintenance of the generator.

A second maintenance period is scheduled from 11pm on Wednesday until 5am on Thursday.

Residents in Broken Hill, Tibooburra, Wilcannia, Menindee, White Cliffs and several other surrounding communities are expected to be impacted.

On Saturday, the government said the generator was "not adequate" to meet full demand, especially during the evening peak between 5:30pm and 10:30pm, and urged residents to conserve power to reduce the risk of rolling blackouts. 

"Power supplies were maintained to Broken Hill and nearby communities via the large-scale back-up generator, thanks to the many households and businesses which conserved power during last night's peak," NSW Energy Minister Penny Sharpe said on Sunday.

"[But] in order to maintain the large-scale back-up generator, Transgrid has advised the far west region of NSW will be without power tonight and again on Wednesday night. We understand this is frustrating for residents, but it is crucial to maintaining the supply."

The government said reliance on generator power in the far west of the state would continue while Transgrid built temporary towers to replace those damaged by the weather — a task that could take weeks.

"There is still a lot of work to be done to replace the transmission towers and repair the electricity network," Ms Sharpe said.

In the meantime, residents in the impacted area have been urged to continue to minimise their evening electricity usage over the next few weeks to reduce demand.

"Instead of using the dishwasher, maybe wash your dishes in the sink. Have a barbecue with paper plates perhaps, turn off the pool pump every second day," independent local MP Roy Butler.

"Just try and do little bits to reduce the amount of power. If you're not in the room, turn the light off.

A separate burst of wild weather on Thursday also knocked out the power supply to parts of South Australia's far north.

However, SA Power Networks said that as of Saturday afternoon, "fewer than 1,000 customers remain without power", after supply was restored to Quorn on Friday night.

"It may still be a few days before we can connect generation to Hawker and Leigh Creek due to the technical complexity," it said.

On Saturday, Mr Butler said four additional generators were "en route to Broken Hill" and would be "plugged in at a substation".

"The idea is that we'll island those smaller communities like Wilcannia, Menindee, White Cliffs, Tibooburra, Milparinka [and] Packsaddle and give them reliability, but also take a bit of pressure off the old turbine generator in Broken Hill," he said.

Mr Butler said mining companies were having "to make some commercial decisions" about what steps they would take.

"I understand that one of them's actually bringing in generators at a very high price to be able to operate because they want to keep their people working," he said.

The Bureau of Meteorology has described the damage to infrastructure as consistent with the "possible presence of a tornado".

"Australia experiences 30 to 80 tornadoes each year, but it is possible that many more tornadoes occur in remote, unpopulated parts of Australia and therefore go unreported," a bureau spokesperson said on Friday.

In South Australia's far north, Roxby Downs Council chief executive Roy Blight said gusts of around 130 kilometres per hour had caused a sandstorm on Thursday afternoon.

"The sky was red, and it was like being sandblasted," he told ABC Radio Adelaide on Friday.

"I saw images of a semi-trailer around Pimba that was blown on its side, and also a vehicle that was down at Oak Dam was going through the weather and hail stones or flying debris smashed the side window."