The City of Kalgoorlie-Boulder mayor says the state government needs to act faster to secure reliable power for his region, amid fears continued blackouts are damaging economic prospects and putting residents at risk. 

Eight months after much of WA's Goldfields and Wheatbelt sweltered through a summer heatwave without electricity, locals were forced to close businesses, cancel events and wait out another major blackout on Friday. 

About 20,000 Western Power customers across Kalgoorlie, Coolgardie, Southern Cross, Lake Grace, Newdegate and Bruce Rock were impacted, with some losing power at 11:15am and most back online by 7pm. 

Many also lost phone, internet and EFTPOS services.

Western Power said a fault with its main 220 kilovolt transmission line, which feeds power into both regions from Synergy's Muja power station near Collie, caused the blackout.

A spokesperson said backup generators were not required, as they take a few hours to fire up and it was faster to "reconfigure the network in a phased approach".

"The line was gradually re-energised in sections to ensure the safe restoration of power," a spokesperson said.

"As the network is monitored digitally and remotely, when there is a fault it takes time to identify the exact location of the fault and the damage that has occurred."

Concerns about economy

The state government has promised to replace Kalgoorlie's aging gas-fired backup generators after they failed during the January power outage, but the extra capacity is not likely to be available until at least 2026.

City of Kalgoorlie-Boulder Mayor Glenn Wilson said suggestions were coming thick and fast on how to improve power stability in the future, and he had sat through 10-12 presentations on the subject since January.

But he said the real question was how to prevent blackouts in the short term. 

He worried further outages would take a toll on the region's economy.  

"We're not going to grow our processing capabilities, and we're not going to get any interest from anyone to do any downstream processing in our region if businesses and industries are still continuing to face this, alongside residents," he said.

At a press conference on Saturday, Energy Minister Reece Whitby said he did not have details about what caused Friday's outage. 

But he said ensuring the region had reliable power supply was a priority.

"I just wanted to say to everyone in Kalgoorlie that lost power that I'm incredibly empathetic with your situation. I'm sorry that you lost power," he said.

'Just terrible'

Everett Butchers' Ngawai Anglesey said following the January blackout — when the Kalgoorlie business reportedly lost about $100,000 worth of stock — the business had purchased a generator, which allowed them to keep doors open on Friday.

But she said EFTPOS services were down and many customers were unable to withdraw cash at ATMs, forcing the business to turn away some customers.

Gary Paul, a vision-impaired Kalgoorlie resident in his 70s, said he had also purchased a generator after the January power outage.

"It saved my bacon really," he said on Saturday morning. 

"It kept my beer cold and my dinner frozen."

But he said forking out $1,000 for the second-hand generator was a big deal as a pensioner, and without access to phone services he still felt vulnerable. 

"It's just terrible," he said.

"What happens to those vulnerable people, especially when you can't get mobile coverage?"