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Two Eastern Cape metropolitan municipalities will join the country's four others in a global environmental competition.
Nelson Mandela Bay and Buffalo City are taking part in the World Wildlife Fund's Earth Hour City Challenge.
WWF says the Metros are busy registering their entries on the carbon Cities Climate Registry, an internationally recognised carbon reporting platform managed by ICLEI Local Governments for Sustainability.
Spokesperson Steven Bland says Earth Hour Cities challenge is all about celebrating the successes of the work that municipalities are doing across South Africa to tackle the challenge of climate change.
"They are going to be judged by an international jury in order to choose one winner from South Africa who will enter the global competition and the criteria for entry are that the municipality must have a specific target and policy relating to emission reductions and energy use and they must show that they are taking bold and ambitious actions to support their residence to reduce their energy bills and build a better quality of life in the city" Bland said.
