The failure of the northern grid brought to a halt more than 500 trains, including 300 passenger trains, on Monday morning.

Most of the trains bound here on the Howrah-Delhi route screeched to a halt at Etawah in Uttar Pradesh when the power breakdown hit the Delhi, Ambala, Agra, Allahabad, Jhansi, Kota and Moradabad divisions.

Trains were stranded at Ambala, Kurukshetra, Ludhiana, Phagwara and Karnal.

Even the signal system had gone blank. Among the passenger trains affected were the Delhi-bound Rajdhani trains from Bhubaneswar, Howrah, Sealdah, Mumbai and Ranchi.

Services were badly affected in Chandigarh, Punjab and Haryana, and diesel engines were pressed into service.

The Railways drew power from other grids in Uttar Pradesh which helped the movement of trains in the Bina-Mathura and Kota-Mathura sections.

Several trains continue to run up to eight hours behind schedule after the restoration of power. Several trains have been rescheduled.

To cope with the recurring problem, the Railways initiated a move to set up their own power plants but these efforts have not borne fruit.

The organisation needs about 4000 MW daily and it consumed 16.65 billion units annually.

The Railways are setting up a 1,000-MW thermal plant at Nabinagar in Bihar jointly with NTPC, which is expected to be commissioned in 2014. It proposes to set up a coal-based 1,320-MW plant at Adra in West Bengal and a 700-MW gas-based one at Thakhurli in Maharashtra.