New Delhi: Earth Hour is become a phenomenon in the cyber space as more people are coming forward to pledge for the cause of the Earth by switching off their lights for an hour on March 26 every year, World Wild Life (WWF) Director General Jim Leape said. "Around 2.25 percent tweets on social networking website Twitter and 880 searches per second on Google were about Earth Hour last year," Leape. Organised by WWF, the lights-off every year at 8.30 p.m. on March 26 is the biggest mobilisation against global warming. "It is much more than energy saving. It is about making a statement for the cause of earth," Leape said. The phenomenon has multiplied with increasing support from celebrities. "There were more than 5,94,000 hits for Earth Hour after Bollywood actor Vidya Balan pledged to support the movement Tuesday," said Ravi Singh, secretary general and chief executive of WWF-India. Earth Hour started in 2007 in Sydney, Australia when 2.2 million individuals and over 2,000 businesses turned their off lights for one hour to take a stand against climate change. India joined the campaign in 2009. Presently, mainly the urban centres in the country are participating. "This year, around 50 cities, 11,957 educational institutions, corporates and many small NGOs have pledged to observe the Earth Hour," Singh said Environment Ministry secretary Dharmendra said: "The government has appealed to over 2,000 schools, 2,000 Resident Welfare Associations, about 100 colleges, malls and hotels in the capital to switch off non-essential lights during the Earth Hour." "Delhi saved 300 MW of electricity during the 2010 Earth Hour," he added.