Those without previous convictions would pay R500 each, and those with previous convictions would pay R1500 each. Five of the accused had previous convictions.

Charges of intimidation and malicious damage to property were dropped.

The group were arrested at Eskom's head office at Megawatt Park, in Johannesburg, on Tuesday.

Twelve of them were from Greenpeace, one was from groundWork, and another from Earthlife Africa. The organisations campaign for environmental protection, clean air, and renewable energy.

The group had climbed the building's roof structure to unfurl a banner across the front entrance reading: "Eskom is under new management".

Several others chained themselves to a door and table outside the building in protest against Eskom's continued reliance on coal and the parastatal's application to again raise electricity tariffs.

Police cut their chains, handcuffed them, and took them to the Sandton police station.

They were released on R500 bail each at 11pm on Tuesday. The court warned of direct imprisonment if they transgressed again.

On Monday, Eskom submitted an application to the National Energy Regulator of SA for a 16 percent tariff hike every year for the next five years.