NTPC Ltd, India’s biggest power producer, said it plans to spend as much as $15 billion (Rs 82, 521 crore) over a decade to secure overseas coal supplies as prices of the fuel tumble to a 19-month-low.

The utility may sign five- or 10-year contracts for the first time to import as much as 150 million metric tonnes of coal, Chairman Arup Roy Choudhury said by telephone from New Delhi on Tuesday.