Indian utilities are scrambling to secure coal supplies as inventories hit critically low levels. Here is a brief summary of the factors that have led to the country's coal shortage. WHAT ARE THE CURRENT STOCK LEVELS? As at Sept. 29, 16 of India's 135 coal-fired power plants had zero coal stocks, according to the Central Electricity Authority (CEA). Over half of the plants had stocks that would last fewer than three days, while over 80% had less than a week. WHAT CAUSED THE COAL SHORTAGE? India's industrial power demand has surged after the second coronavirus pandemic wave. On top of that, a widening price gap between lower domestic prices and record global coal prices has led buyers to shun imports. State-run Coal India NSE 1.94 %, which produces over 80% of India's coal, on Wednesday said an increase in global coal prices and freight costs had led to a curtailment.