 Delhi Metro Rail Corporation Limited ( DMRC ) , a state @-@ owned company with equal equity participation from Government of India and Government of Delhi , built and operates the Delhi Metro . The Delhi Metro Rail Corporation has been certified by the United Nations as the first metro rail and rail @-@ based system in the world to get " carbon credits for reducing greenhouse gas emissions " and helping in reducing pollution levels in the city by 630 @,@ 000 tonnes every year . DMRC operates around 2000 trips daily between 05 : 30 till 00 : 00 running with a headway varying between 1 – 2 minutes and 4 – 10 minutes . The trains are usually of four , six and eight @-@ coach . The power output is supplied by 25 @-@ kilovolt , 50 @-@ hertz alternating current through overhead catenary . 
