Text of my ‘When Worlds Collide’ column published in Ceylon Today Sunday newspaper on 25 March 2012

This year’s Earth Hour will be observed worldwide on Saturday 31 March 2012. That evening, millions of businesses and households will voluntarily switch off some or most night lights from 8.30 to 9.30 pm local time.

Earth Hour is an annual event to raise awareness on saving energy and taking personal action to mitigate climate change. It started in Australia in early 2007, when the Sydney Morning Herald newspaper asked its readers to join a synchronised switching off of non-essential lights for one hour.

Five years on, Earth Hour has grown into a truly global event. In 2011, it took place in a record 5,251 cities and towns in 135 countries and territories, with an estimated reach of 1.8 billion people.

Earth Hour is largely symbolic – we can’t save enough electricity in…