On Saturday, October 20, 2007, from 8:00 p.m. to 9:00 p.m., involved homeowners, businesses, and schools in San Francisco and Los Angeles will install one compact fluorescent bulb and turn off all non-essential lighting for one hour as part of the first "Lights Out San Francisco" energy conservation initiative. The event aims to save as much as 15 percent of the energy consumed on an average Saturday night, mitigating the effects of climate change by reducing greenhouse gas emissions, and raising consciousness of how simple it can be to save energy and fight climate change. A similar, unrelated event took place in Utah on September 19, 2007, called "Lights Off Utah."

Nathan Tyler, the founder and executive director of "Lights Out San Francisco," says he decided to launch his initiative after a vacation in March 2007 to Sydney, Australia, where he experienced the city's "Earth Hour," in which 2.2 million people turned off their non-essential lighting for one hour. According to WWF-Australia, the organizers of "Earth Hour," the event reduced energy usage by 10.2 percent and prevented 24.86 tons of carbon dioxide from being released into the air.

Tyler estimates the latest count for participants in San Francisco and L.A. will be a few hundred, based on the number of sign-ups completed on the event's website, www.lightsoutsf.org. "We've got the Bay Bridge, the Golden Gate Bridge, City Hall, the Transamerica Tower, and other local businesses turning off their lights in support of this initiative," Tyler says.

Tyler also is organizing "Lights Out America," a national energy savings event, scheduled for March 29, 2008. Visit the website at www.lightsoutamerica.org.