India is boosting coal production to record highs in an effort to overcome a fuel shortage that has strained the power supply, leading to blackouts during a searing heatwave on the subcontinent.

Officials and analysts expect India to bump up coal production after the supply crunch prompted fears about the country’s energy security. Care Edge, a ratings and research group, said it expected India to mine more than 800mn tonnes of coal in the financial year that started in April.

Pralhad Joshi, India’s coal minister, said on Twitter that state-run Coal India, the world’s largest coal miner, increased output in April to 53-47mn tonnes, 6 percent higher than the same month in 2019 before the coronavirus pandemic struck. Coal India “is furthering India’s energy security”, Joshi wrote.

India is the world’s second-largest coal producer and consumer and depends on fossil fuels for about 70 percent of power generation. But the combination of surging demand as economic activity rebounds after Covid restrictions were eased and supply chain bottlenecks, such as a lack of rail cars to transport coal, have left many plants plagued by shortages.

Before the war in Ukraine, India had increased imports of Russian coal to bolster supplies. But Tata Steel, the largest importer of Russian coal, said it would stop buying the commodity owing to “uncertainties” in the supply chain.

Last week, an official in New Delhi said the megacity had only days’ worth of coal supply left.

At least 18 power plants are offline owing to the coal shortage, according to the latest daily report from India’s Central Electricity Authority. Most of the plants are in the country’s broiling northern states.

Supply concerns have been exacerbated by the recent heatwave, which has sent temperatures across swaths of India to record levels well above 40C. Industries and households have cranked up air conditioning to counter the soaring