Tomorrow, Saturday March 28th, 2009 from 8:30-9:30 pm (local time) cities around the world are going dark for Earth Hour.

World Wildlife Fund (WWF) organizes the event where millions of individuals and cities around the world turn off their non-essential lights for an hour.

Here are some he sites that will have lights out on Saturday night:

• Toronto: CN Tower
• Rio de Janeiro: Christ the Redeemer Statue
• Sydney: Opera House
• Hong Kong: Symphony of Lights Show
• Moscow: Moscow State University
• Paris: Eiffel Tower
• Cape Town: Table Mountain

Check out some photos from last year in Sydney:

Sydney Before Earth Hour

photo credit: Erik Panch

Sydney During Earth Hour

photo credit: Erik Panch

From the FAQ’s of the Earth Hour Site:

10. Do I have to turn off all of my electricity for Earth Hour?

Not at all. Through Earth Hour we are asking people to turn off all non-essential lighting. Emergency lighting, televisions and computers can stay on for the hour. The main point of Earth Hour is to unite people, companies and governments around the world through the symbolic flip of a switch. Earth Hour in itself will not lower our carbon footprint, rather it sends a signal to those in a place of power that we as individuals and communities demand action.

The decision on which lights to turn off can be made individually, but usually consists of overhead lights in rooms (whether it is your house or a business), outdoor lighting that does not impact safety, computers, decorative lights, neon signs for advertising, televisions, desk lamps, etc.

11. Will my city go completely black?

Earth Hour is not a black out. It is a voluntary power down of non-essential, decorative lighting by its participants. For many businesses in city skyscrapers or for many government buildings the lights are turned off at the end of the business day the Friday before Earth Hour and won’t go back on until that Monday morning, so the event will be more of a fade to gray than an abrupt shift to black. There is usually no instant dramatic difference, but rather a gradual power down starting the day prior.

So, if you don’t already turn off all non-essential lighting (hopefully do you), make the effort to do so for an hour tomorrow.

You can find out more about Earth Hour at EarthHour.org