A passenger looks through the window of a train as he waits for electricity to be restored at a railway station in New Delhi July 31, 2012. Grid failure hit India for a second day on Tuesday, cutting power to hundreds of millions of people in the populous northern and eastern states including the capital Delhi and major cities such as Kolkata. [Photo/Agencies]

Passengers crowd at a railway station as they sit on tracks while waiting for the electricity to be restored in Kolkata July 31, 2012. Grids supplying electricity to half of India's 1.2 billion people collapsed on Tuesday, trapping coal miners, stranding train travellers and plunging hospitals into darkness in the second major blackout in as many days. [Photo/Agencies]