Officials in India on November 6 said the death toll has risen to 35 after an explosion and fire November 1 at NTPC’s Feroze Gandhi Unchahar Thermal Power Station in Uttar Pradesh state. NTPC, the nation’s largest power utility, said flue gases and steam were released in the blast, which occurred in a 500-MW coal-fired unit that was commissioned in March and had been operating on a trial basis at the plant since September.
NTPC officials investigating the incident said November 3 that pressure inside the unit shot up to 70 times its normal level in just a few minutes before the explosion, and an emergency shut-off mechanism that should have disabled the unit apparently failed to work. A fireball exploded in the unit and pressurized steam gushed out onto dozens of workers, who were either killed or severely burned.
Local hospital officials say several workers severely burned in the incident remain hospitalized.
Federal Power Secretary A.K. Bhalla told local media that along with NTPC executives, officials from Bharat Heavy Electricals Ltd. (BHEL), which supplied the boiler for the unit, are involved in the investigation into the blast.
NTPC in a statement said there had been an “sudden abnormal sound” and an escape of gases and steam prior to the blast. A local police official in a statement said preliminary findings indicate coal ash had collected in the furnace below the boiler, and “pressure built up inside and led to the blast.”
India’s NDTV on November 3 said NTPC officials have admitted that engineers were aware of the ash problem and were trying to clean the unit without shutting it down.
Shailendra Dubey, who leads the All India Power Engineers Federation, told NDTV that the unit should have been shut down for cleaning because it was new. “It was commissioned in March hurriedly … it seems work was actually not completed,” he said.
RS Rathee, regional executive director of NTPC, told reporters on November 2 that “It is normal procedure that we carry out repair work when plants are still working. Shutting down a plant is a decision we take later. All our officers are experienced. The decisions were taken by them. It’s not that we shut down a plant at the first problem.”
A senior NTPC executive who asked not to be named told the Hindustan Times: “There was an explosion inside the boiler. After the coal burns it gets deposited and has to be cleared. The people who died were engaged in cleaning.”
Ram Prakash, a worker at the plant, told the Times: “I saw heaps of dead and badly burned bodies, there were cries for help when I reached the spot almost 15 minutes after the blast. It was a horrible scene.”
The death toll is among the highest from a power-plant accident in recent years. An explosion at a hydropower station in Siberia in 2009 killed 75 people, and there were 74 deaths reported in November 2016 from the collapse of a platform at a coal-fired power plant under construction in China. Officials said it is the worst industrial accident in India since 45 people were killed by the collapse of a chimney being built at Bharat Aluminum Co.’s Korba thermal plant project in 2009.
— Insaan Pareshan (@InsaanPareshan) November 1, 2017
Industrial accidents are not rare in India, due to lax government standards for workplace safety—data from the federal home ministry reports 831 deaths were caused by accidental explosions in 2015—but power plant safety measures have improved in recent years and NTPC has one of the country’s best safety records.
Ravi Krishnan, an energy industry consultant in the U.S. and India, told the Insurance Journal that NTPC “[has] some of the best operating practices. It surprised me when I saw this, it doesn’t happen very frequently.”
The Feroze Gandhi plant is named for the husband of former Prime Minister Indira Gandhi. It began commercial operation in 1988. The plant employs 870 workers, and it was not known how many were in the plant at the time of the explosion. The plant has six units and a total generation capacity of 1,550 MW. The affected unit was shut down after the blast; two 210-MW units are offline due to lack of power demand, and three units generating a combined 630 MW of power remain in operation, according to NTPC.
—Darrell Proctor is a POWER associate editor (@DarrellProctor1, @POWERmagazine)