All you need to charge your mobile is -- air! Students at the Department of Industrial Design at Indian Institute of Technology, Delhi have attached a turbine with a mobile phone that helps charge it even when the user is travelling, Head of the Department Professor Lalit Kumar Das told PTI. "The electricity generated by the turbine when moved by wind energy could charge a cellphone in an emergency. It generates electricity to the tune of 3 to 4 watts which is sufficient to charge a mobile phone," he said.