Earth Hour to Turn 131 Countries Dark This Weekend

Critics say the annual energy-conscious event is an empty gesture.

Up to a billion people are expected to participate in Earth Hour this weekend by turning off their lights between 8:30 and 9:30 p.m. Saturday night. The event was kick-started five years ago in Sydney, Australia, by the World Wildlife Fund and has grown larger every year. For the 2011 event, 131 countries have registered, up from 126 a year ago. Earth Hour is intended to draw attention to humanity’s environmentally costly demand for energy, but many believe the momentary reduction in power consumption does little to actually combat the problem. Cities participating in Earth Hour aim for a 10 per cent reduction in energy consumption during the event.