Businesses are losing billions of rand not only through load-shedding but because Eskom sometimes fails to stick to power outage schedules.

Eskom is implementing load-shedding as demand for power outstrips supply. There are technical problems at some of Eskom’s power plants.

South African Chamber of Commerce and Industry (Sacci) acting CEO Peggy Drodskie said power outages were taking their toll on small businesses.

"You tell your staff you needn’t come to work today because there is not going to be electricity, and then you find there is electricity and you’ve lost production," she said.

The chamber has called for an electricity summit. "This summit is something where we need to put everything on the table and we need to thrash out common objectives and common remedies to the problems," Ms Drodskie said.

The chamber released an index on Thursday that showed that business confidence improved slightly in January. The business confidence index rose one index point to 89.3.

Sacci economic consultant Richard Downing said factors, including a stable supply of electricity, making it easier for foreigners with critical skills to acquire work visas and policy certainty would help lift business confidence.

The index is not a survey of sentiment among business people but is compiled from tracking key economic indicators such as the rand, share prices, inflation and manufacturing.

Vehicle sales, real private sector borrowing and real financing costs fell during the month, while exports, retail sales and precious metal prices improved.