Here are the latest developments in this story:
The unions had boycotted a meeting called by minister Piyush Goyal on Saturday. Today's meeting is on, Mr Goyal has confirmed. The unions are opposing the government's coal block ordinance, which may allow private companies to mine and sell coal commercially.
All 36 mines of Western Coalfield Ltd, one of 8 subsidiary companies of Coal India, are shut. By the afternoon of the first day's strike, production by South Eastern Coalfield Limited was down by 2.5 lakh metric tonnes. On an average, it produces 4-5 lakh metric tonnes of coal a day.
The strike is likely to result in production loss of up to 1.5 million tonnes a day -- which means a five-day strike can hit output by 8 million tonnes. Coal is the most dominant energy source in India, meeting around 52% of the primary commercial energy needs.
As of January 1, coal inventory at power plants stood at nine days. But 20 power plants have coal stocks of less than four days.
Coal India Limited produces around 80 per cent of India's overall coal and feeds 82 of the 86 coal-based thermal power plants.
Its subsidiary, the South Eastern Coalfield Limited, mines coal across Chhattisgarh and Madhya Pradesh - two of the key coal producing states. It also exports coal to Gujarat. At the moment, it has stocks for two days, after which supplies will get hit.
The management of Coal India Limited had appealed to unions not to go on strike, saying power production across the country could be hit if coal is not transported on time to power plants.
Coal India also stepped up supplies to the power plants to tide over the disruption of supplies. "CIL is supplying extra volumes of coal to the power plants and the Railways is fully cooperating with the coal PSU," an official said.
India is the third largest coal producing country in the world after China and the USA.
The five major trade unions backing the strike - Bharatiya Mazdoor Sangh (BMS), Indian National Trade Union Congress (INTUC), All India Trade Union Congress (AITUC), Confederation of Indian Trade Unions (CITU) and Hind Mazdoor Sangh - represent almost 90% of Coal India's half-a-million workforce.
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