Automotive plants across South Africa were shuttered Wednesday as workers joined tens of thousands of strikers protesting against rising electricity prices.

The one-day national strike, called by the Congress of South African Trade Unions (COSATU), is calling for a 27.5 per cent power price hike this year to be rolled back and guarantees jobs won't be cut due to power shortages.

South Africa's electricity crisis, which has resulted in intermittent power cuts as provider Eskom struggles to meet demand, has forced shutdowns in the mining sector in recent months, leading to warnings that thousands of jobs will be lost.

The price of electricity has soared because of the shortages, adding to the rising cost of living in Africa's richest nation. COSATU has already held three provincial strikes and is pledging to continue its protests until the government takes action to control inflation that has topped 11 per cent.

Volkswagen AG's South African unit was forced to suspend scheduled production for the day at its main Uitenhage plant in the south, which normally produced between 300 and 350 vehicles daily, said spokesman Bill Stephens.

He said the company would have to make up production of vehicles destined for export. The company expects to produce about 40,000 vehicles this year, of which 40 per cent would be exported.

Ford Motor Co. of Southern Africa, the regional arm of the Michigan-based automaker, had production of about 340 vehicles and 600 engines disrupted for the day after the strike closed its Port Elizabeth and Silverton plants, spokesman Lloyd Marlowe said.

Marlowe said it was possible the company would be able to make up for the lost production in the quarter.

Nissan Motor Co.'s local arm suspended operations at its plant in Rosslyn, which had output of roughly 280 vehicles a day, and Mercedes-Benz South Africa, which produces about 220 vehicles a day, had earlier in the week said it would close its factory while the strike took place.

Nissan spokesperson Veralda Schimdt confirmed that the carmaker was running a shorter working week and that it would not be making up for the hours lost. One thousand of the plant's employees are taking part in the strike, she said

"Mercedes-Benz SA management acknowledges the very real problems associated with the present economic climate, but has pointed out that the solution does not lie in stopping production," said Annelise van der Laan, spokesperson for Mercedes-Benz SA.

Van der Laan added that Mercedes Benz said that should it be necessary to recover production due to sales demand, arrangements would be made between the company and the unions.