Before you decide if you’re On or Off, skim through these basic facts and arguments:
What is it?
Earth Hour 2016 is 19 March, 20h30-21h30. The concept is that everyone on the planet who cares about the environment and the impact of climate change will be switching off their lights for that hour.
The World Wide Fund for Nature (WWF) calls it "the single, largest, symbolic mass participation event in the world".
This year, the South African campaign focuses on food, energy, water and waste - challenging individuals, communities, schools, businesses and municipalities to take the lead on climate action.
Through our interactive pledge platform, all South Africans are being called upon to take small actions that collectively translate into a big impact on climate change.
Join WWF South Africa as we encourage all people to help us by becoming motivators and climate champions for the Earth.
Track South Africa during Earth Hour 2016 and find out what's going on during Earth Hour around SA.
But why? What's the point?
The Big Lights Out is a simple, dramatic way to send a message to the world's leaders, big business and everyone else that we're sick of conversation without action.
What are the arguments against Earth Hour?
Earth Hour has been roundly criticized as an empty gesture – yet another way for the leisured classes to salve their collective environmental conscience without actually doing anything constructive to make a real difference.
Watch: Why Earth Hour matters
Well, isn’t it kind of empty?
Only if we allow it to be: the aim is raising awareness; the hope is that action will follow from awareness. In itself, Earth Hour is not trying to save energy; it's trying to stimulate change that will result in meaningful change.
Are people really going to go for this?
Some of us certainly are. The organisers estimate that Earth Hour now involves millions of people across 172 countries and territories.
See: Map of countries participating in Earth Hour. Source: EarthHour.org
Are you supposed to just switch off your lights or everything electrical?
That's up to you, but I think it's kind of missing the point to turn the lights off and then stick a load of washing in the tumbledryer.
Is everyone switching off at the same time?
Everyone is switching off when the clock strikes 20h30, wherever they are. (If the whole world switched off simultaneously, then some people would be doing so in broad daylight, which wouldn't be much fun.)
What are we supposed to do for that hour?
Anything you like. Some people will be having full-out Earth Hour parties in the dark, others more genteel candle-lit sit-downs.
Some are just going to mellow out and enjoy an hour free of light pollution. (Though keep in mind it's probably best to stay off the darkened streets, and watch out for the naked flames of all those candles...)