Eskom may not have enough power during peak hours for platinum mines in the Rustenburg area to resume operations when the strike is finally resolved.
Business Unity South Africa has urged Eskom to let it help find ways to improve the power parastatal's sustainability and avoid a tariff hike.
Emissions obligations weigh as heavily on the state-owned power firm's bottom line as its customers' health and safety.
The Democratic Republic of Congo has halted mining expansion projects due to a power shortage that has it considering a "load-shedding" schedule.
President Barack Obama is due to announce on Sunday a $7-billion initiative over five years to double access to power in sub-Saharan Africa.
Southern African countries bear the brunt of ambitious plans gone awry, writes Roman Grynberg.
Limpopo residents on Tuesday filed a complaint with the World Bank about the $3,75bn loan sought by Eskom to help finance the Medudi power plant.
SA's power supply is seen as a serious concern from 2011 onwards until new power stations come on stream, Eskom said on Tuesday.