• A second explosion at the Mayfair substation has left thousands of Johannesburg residents without power, including areas that had electricity before.

• City Power is repairing damaged cables and looking for other ways to restore electricity, but cannot say when everyone will have power again.

Thousands of Johannesburg families are struggling without electricity after a second explosion at the Mayfair substation made an already bad power outage even worse.

The explosion happened at about 6pm when City Power workers tried to switch the electricity back on.

The power came back for only a few minutes before another explosion knocked it out again.

Even homes and businesses that had escaped the first power cut were left in the dark.

The outage has affected Mayfair, Crown, Vrededorp, Brixton, Crosby, Pageview, Homestead Park and Amalgam.

The South African Broadcasting Corporation in Auckland Park and Garden City Hospital in Mayfair have also been affected.

For ordinary residents, the outage means more than sitting in the dark.

Families cannot use their fridges, cook on electric stoves or charge their phones. Small businesses that need electricity to operate are also facing problems.

Hospitals and water services have also been affected, making the power cut even more serious.

City Power spokesperson Isaac Mangena said the second explosion caused major damage.

Firefighters had to make sure the substation was safe before workers could go back inside.

This delayed repairs by almost 12 hours.

Workers have since started removing burnt equipment, cleaning damaged parts and replacing cables.

City Power is also looking at using the Hursthill substation to supply electricity to some areas while repairs continue.

Mangena said teams were making progress on cables supplying the South African Broadcasting Corporation and hoped to restore its electricity by Wednesday afternoon.

He said workers were also hoping to restore power to some other affected areas by Wednesday evening if repairs went according to plan.

But residents in Brixton, Crosby and Pageview were still without electricity.

City Power said hospitals and other important services were being given priority.

The cause of the explosion is still unknown and City Power is investigating what went wrong.

The biggest worry for residents is that there is still no confirmed time for everyone to get their electricity back.

For families already battling the high cost of living, a long power cut can mean spoiled food, extra costs and lost income for people who depend on electricity to work.

City Power says its teams are working to restore supply, but residents will have to wait until the damaged equipment is repaired and it is safe to switch the power back on.