The government is committed to keeping the lights on even though power generation is under pressure, Public Enterprises Minister Malusi Gigaba said on Monday.

He told a business executive meeting in Pretoria that this commitment to an uninterrupted electricity supply did not depend only on the government.

"I trust we shall all heed the call for efficient and prudent usage of electricity. We remain resolute in our efforts to keep the lights on during this supply-constrained environment we are currently in," he said.

"Accordingly, we continue to rely on all South Africans – both individuals and corporates – to continue reducing demand and saving electricity by implementing the tips we give them through the media. We cannot do this on our own."

Gigaba said illegal power connections were a major obstacle to a constant power supply.

"We need the effort of every single person of the 49-million [South Africans]. This means we must continue to curb illegal connections and cable theft, which increase network overload and equipment failure," he said.

"This causes the system to trip and results in localised power outages in the distribution networks in areas such as Gauteng. We continue working together with the police and municipalities to raise awareness in this regard," said Gigaba.

He said many companies had made significant contributions to energy saving under the 49M energy-saving campaign over the past three years.

"However, more commitment is still needed from you [the business community] in the coming months and over the next year to ensure the lights stay on.

"This will ensure that economic growth and jobs are not put at risk.

"The same is expected from households, the majority of whom are supplied by municipalities. Our call for energy efficiency is not new and we thank those partnering with us in the 49M campaign," Gigaba said.

"The state of the power system needs urgent and immediate action to enable Eskom to meet the demand and keep the sufficient reserves for emergencies," he said.

"We cannot, as a country, continue to keep the lights on in the short term in a way that undermines doing the same in the long term."

Eskom has urged all South Africans to continue using electricity sparingly, as power generation remains under severe pressure.

The power utility's chairman Zola Tsotsi said future generations would suffer if energy saving was not prioritised by every individual in the country.

"We may be a small group sitting in this room, but everyone of us has the power to save electricity. If we start exercising that power now, we would change the way people around us use energy," he said.

"We all know that resources used to produce energy are limited and if we continue to take these resources for granted and we continue to waste energy, our future generations will not have enough to produce the energy required," said Tsotsi.

"Let's make a difference, the gains are limitless. If you are not using it, switch it off. Use power to save it. This is a call to action for everyone to be energy efficient," he said.