It is a symbolic and often spectacular display by hundreds of millions of people around the world who show they care about the planet – and every year it fills my heart.
When I was writing about the environment fulltime it could sometimes feel like I was fighting a lonely battle with almost every story getting the same old people commenting that it was a waste of time (or often that I was a waste of time).
And then, each year, Earth Hour would come along and those few but loud voices would be drowned out by people coming together for an event (created in 2007 by a man originally from Norfolk) which was all about silence – or at least quieting the hum of power for an hour.
If you’re not aware, from 8.30pm for one hour people are asked to turn off everything non-essential – a reminder that when lots of people come together they can make a huge difference.
Last year a record 162 countries took part but you don’t have to sit at home alone in the dark (unless you want to enjoy the peace, which is actually quite nice) because there are events held all over the place.
As a family, we have been joining in almost from the start and have enjoyed everything from candle-lit dinners at home to fire-juggling and music while out and about.
Check out www.earthhour.wwf.org.uk and you can find stuff to do near you in the UK or, this year, people are being challenged to craft some bunting, which I am a fan of, during their hour.