Calcutta, July 23: South Bengal suffered severe power cuts today as generation by state-run power plants dwindled and demand went up with the mercury.

The combined shortfall in the CESC and the State Electricity Distribution Company areas shot up to 765MW in the evening peak hours.

The situation is likely to remain grim tomorrow with power officials not sure about when supply would improve and the weather office predicting a hot spell.

In the city, power cuts ranged from two-and-a-half to three hours between morning and afternoon. As dusk set in, vast areas plunged into darkness for hours.

The situation in the districts was worse as the deficit shot up to 550MW. Outages lasted between five-and-a-half and six hours.

A power department official said the demand had gone up over the past three days because of the humidity. “In Calcutta alone it has gone up around 80MW in four days. This evening, the demand in CESC areas was 1,443MW. In the districts the demand this evening was over 2,900MW, over 100 more than last week.”

The Met office said there was little chance of heavy rain in Calcutta and the neighbouring districts in 48 hours.

Power department offici- als, though, blamed regular rain in the Asansol-Durgapur coal belt for the prevailing situation. “Since the heavy rain in mid-June, the coal stocks at the mines haven’t got enough sun to dry. Supply of coal to the Kolaghat and Bakreswar plants has decreased.”

West Bengal Power Development Corporation officials said dwindling coal stocks at Kolaghat, Bakreswar and Bandel power plants had forced them to reduce generation.

“We are living hand to mouth. We have received seven coal rakes instead of the usual 16 at our plants today. If we could generate full steam now, we could have met a substantial chunk of today’s shortfall,” said managing director S. Mahapatra.

But coal isn’t the only culprit. Several units had to be shut down for repairs in the past few days.

A 210MW Bandel unit stopped working on Saturday and a 210MW unit at Kolaghat was shut down this morning after a tube-leak in its boiler. The 300MW Durgapur Projects Ltd unit set up by Chinese company Dong Fang that went into commercial generation only in April, collapsed for the sixth time three days ago.

Power minister Mrinal Banerjee today said in the Assembly that Bengal was not a power-surplus state anymore. “The state is not power surplus. The state is experiencing power cuts because of the gap between demand and supply. Poor quality coal is also hampering generation.”