Power collapse triggers chain reaction

Headlights glimmered on city streets yesterday evening as there were no neon signs, lighted billboards or streetlights. Photo shows the Farmgate area.Photo: STAR

The cyclone caused the country's power system to collapse completely yesterday morning, triggering a knock-on effect on piped water supplies, telecommunication and filling station operations.
In addition to suffering the miseries inflicted by the lack of power and water supplies, people spent a day amid increasing tension and uncertainty.
The lack of power also disconnected people from any television coverage of the events; while the disruption of phone lines kept them worried about their relatives in far off districts--especially those staying in the southwestern region. For the first time in Bangladesh's history, the BTV's transmission was disrupted for three hours from 11:40am.
Road communication was also affected in many nooks and crannies as the cyclone uprooted many trees and structures to create blockade. This has slowed down electricity and telecom restoration works, sources in both power and telecom sectors said.
Due to lack of power supply, Internet connections were also disrupted even for those who were running their computers using generators. This has happened because the Internet service providers had ran out of their backup power systems.
Technicians and experts were working round the clock to restore basic power supply but their attempts failed to ensure electricity for more than a minute in general. This effort was hard hit when the national power grid completely failed for the second time around 5:30pm.
The power blackout started around 7:57am yesterday. Power ministry sources said the power plants of the country tripped due to rapid fall in power demands. Again the power demands dropped due to both planned shut down of power supplies to some areas to avoid accidents and also disruption in the power grid due to the storm.
Though power supply resumed in small proportions around 9:30am, mainly to start up large power plants across the country, there was no electricity apart from a few places till 5:30pm.
At 5:30pm, the country's power grid completely failed for the second time when the Power Development Board (PDB) tried to provide only 650MW power against a surging electricity demand.
Around 11:00pm, the PDB was able to supply up to 800MW power to different important areas. The PDB was hoping to increase power supplies to 2000MW by early morning adding power generated from Meghnaghat and Haripur power plants.
The last blackout had taken place in 2003.
City and town dwellers across the country dependent on piped water started to feel uneasy when they realised by 11:00am that it would take many hours before the PDB can restore power. As they could not start up water pumps, there was no water supply in most houses by noon. Cooking and hygiene maintenance were affected.
According to a press release, using 264 generators the Dhaka Wasa is trying to maintain limited water supply in the city that consumes 2.23 crore litres of water daily. The Wasa claimed that it was expecting to restore normal water supply within 24 hours.
Secretary to the power division M Fouzul Kabir Khan terming the power situation a "national disaster" said, "After the second grid failure at 5:30pm, we are trying to restart the power system with help from the four hydropower units of the Karnaphuli Power Plant."
PDB sources at 7:45pm said earlier yesterday, the PDB had planned to start restoration of power supply with 800MW in the evening and gradually increase the supply to 2200MW by 10:00pm.
"But when we started supplying power to selected areas in Dhaka, the demand was so huge that the system became unstable and the grid failed," said a competent PDB source.
The second grid failure pushed all efforts far behind. PDB and Dhaka Electric Supply Authorities (Desa) were then working with the aim to start off with 600MW power around 9:00pm and gradually increase the supply throughout the night.
TELECOM DISRUPTION
Meanwhile, the cellphone services were disrupted as phone network base stations, most of which are equipped with backup batteries and some with generators, ran out of power. As a result, cellphone service in many areas was unavailable. Base stations, which have generators, were maintaining the networks.
But these generators need to be refuelled till the power system is restored. A Grameenphone source said due to road blockade caused by fallen tree trunks and structures, refuelling vehicles could not reach some base stations in time.
Telecommunication was disrupted specially in the southwestern region, which was hard hit by the cyclone. In many southwestern districts, land telephone lines were disconnected.
A senior executive of Grameenphone said backup batteries that keep a base station running during power outage last for six to eight hours. "Since power supply has not been restored, the back up power is failing. We are now trying to maintain the base stations which are powered by generators," he said.
POWER CRISIS
Power Development Board Chairman Shawkat Ali at a press conference in the evening said power supply may be restored within noon today (Saturday) in the capital and elsewhere except the cyclone hit coastal districts.
He added that it would take a week to restore power supply to the coastal districts where most towers, electric poles and wires were badly damaged.
Shawkat Ali noted, "A disaster descended on the whole power system of the country at 7:59am yesterday when the system collapsed due to huge gap between demand and supply."
He said after relentless efforts they could generate around 650MW by 5:00pm yesterday, but again the system collapsed as demand increased rapidly.
Desa Chairman Brigadier General Nazrul Hasan, Power Grid Company of Bangladesh (PGCB) Managing Director HM Harunur Rashid and Rural Electrification Board (REB) Chairman Habibullah Majumder were present at the press conference at Biddyut Bhaban.
The press asked them whether the grid failure was triggered by lack of coordination between different power generation and distribution bodies or was it because of negligence of officials. They clarified that it happened because there was a sudden surge of demand which could not be synchronised with the supply due to lack of automated equipment.
They said their officials were trying hard to restore the system since yesterday morning.
The PDB chairman said a similar disaster in the power system occurred a decade ago.
PDB sources told The Daily Star that on Thursday night, the power demand hovered around 3400MW. To avoid accidents in the hard-hit southwestern region, the PDB shut down some power lines in Khulna-Bagerhat area.
Normally peak power demands hover around 5000MW, while the PDB can provide 4200MW tops.
"By 1:00am Friday, the power demands came down to 732MW. All private power plants had stopped power supply at that point. At 3:00am, it came down to 346MW. At 7:00 am, it peaked at 440MW. But at 7:57am, the power voltage surged up, causing a fault in the grid system and all the operating power plants tripped," the source said.
To restore the country's power system, the Rural Power Company Ltd (RPCL) started its Mymensingh power plant, which is equipped with a "black start" facility. The black start facility has been installed in only a handful plants to restart the plant within short notice.
RPCL started giving 32MW power to the national grid around 9:45am. This power was being used to start a power unit in Ashuganj, then another in Bheramara and some other smaller gas-fired power plants. The large combined cycle power plants of Ashuganj or Haripur need many hours to heat up and start generating power. Therefore, it was expected that the main power plants would start generating power from the evening.
Power supplies to the Bangabhaban and Prime Minister's Office ware restored around 11:30am. After this, power was being given to hospitals and television channels on urgent basis.