On Saturday, March 28th, approximately 4,000 cities and towns in 88 countries voted for less energy use by flipping off all their lights. In the 60 minutes between 8:30 and 9:30 PM, people united the world over to honor Mother Earth by conserving electricity.

Earth Hour is the brainchild of the World Wildlife Fund (WWF), located in Sydney, Australia. The event began in 2007, when 2.2 million homes and businesses in Sydney unanimously turned off all lights at the time appointed by the WWF, wrapping the vast city in darkness.

By 2008, Earth Hour had gone global, with a recorded 50 million participants worldwide. The United Nations Secretary-General Ban Ki-moon was quoted as saying Earth Hour may become “the largest demonstration of public concern about climate change ever attempted.”

The goal for 2009’s Earth Hour, given the theme “Vote Earth,” was one billion participants. Beginning in New Zealand, cities around the globe cut their lights to vote Earth between 8:30-9:30 PM local time March 28th.

“No matter what your individual beliefs are about climate change, energy efficiency is something everyone can understand in this economic environment,” said WWF’s managing director Darron Collins.

Big names in the entertainment industry, including actors Cate Blanchett and Edward Norton, musicians Alanis Morissette and Big Kenny, and the band Coldplay, came out to show their support for the event.

The 2009 Earth Hour saw the first dimming of the our country’s capital. “This is the first year D.C. has become an official Earth Hour city,” said WWF spokeswoman Leslie Aun.

China also participated for the first time, darkening the infamous Bird’s Nest Stadium and Water Cube in Beijing, both of which held events during the 2008 World Olympics.

Other famous landmarks that joined in the 2009 Earth Hour festivities included the Eiffel Tower, the Empire State Building, the Great Pyramids in Egypt, the Colosseum in Rome, the statue of “Christ the Redeemer” in Rio de Janiero, and the Las Vegas strip.

“Earth Hour has always been a positive campaign; it’s always around street parties, not street protests. It’s the idea of hope, not despair, and I think that’s something that’s been incredibly important this year because there is so much despair around,” said Earth Hour executive Andy Ridley, in a recent interview with Vanessa Gera for Wtop.com.

“The issue is whether it [Earth Hour] goes beyond a ‘really cool’ event, and leads to anything tangible,” said Mary-Elena Carr, associate director of the Columbia Climate Center in New York.

“If there was an idea of how much energy was being saved, people could take measures to lower their energy use in a systematic and practical way,” she explained in an interview with National Geographic.

Though there is no way to measure the total amount of energy saved world wide, specific areas have tallied their total Earth Hour savings. The U.N. building estimated its savings at $102 for the hour. Toronto, Canada, saw an estimated decrease of 15% in energy use, while Delhi, the capital of India, recorded a deficit of 1000 MW of power.

Ireland saved 2% of their total energy use during the hour by flipping off the equivalent of 700,000 lights. This drop in consumption conserved an estimated 70 MW of power, and prevented the release of 30 tonnes of CO2 emissions.

While there is no doubt that blackening such major cities as Washington DC, Sydney, and Beijing will conserve energy, the WWF admits that there is no uniform way to measure just how much energy was saved over the span of the night.

While this fact may be frustrating to some, the knowledge that Earth Hour does indeed preserve energy was enough to inspire almost a billion participants to flip the switch Saturday, March 28, to vote Earth.

“We think the value of Earth Hour is the lights going off, not the actual savings [in energy],” said Aun.

For more information on Earth Hour, you can go to the main website or join the “Earth Hour” facebook group.