Energy & Power

Technology
Earthquake and Power Infrastructure
EP Report

The issue of preparedness and troubleshooting at a proper time is now being followed throughout the world to reduce the loss of property and infrastructure during any natural disaster. Bangladesh, being a third-world country is not out of that practice. Despite flood and cyclone received due importance on the question of facing natural disaster, earthquake is yet to get any due importance. Scientifically, it is not possible to forecast about earthquake, but the system of information collection and building infrastructure in the light of recommendations based upon those information is available in many countries of the world.
Though in late, a national committee had been formed to formulate recommendations to ensure security in the power stations to face the risk of earthquake. University Grants Commission Member Prof Munirul Huq acted as the Convener of this committee, which has recently submitted its report to the government recommending a 14-point suggestions to avert possible losses in the power sector due to earthquake.
Reviewing the impacts of the earthquakes, which took place in July and August, 2003, on the power sector, following recommendations have been made by the committee:

Design of the Power Infrastructure

Seismic zoning map, which is now available for earthquake preparedness, is not the same with the earthquakes took place in Chittagong and Sylhet areas. So this map should be amended soon on urgent basis.

Conducting a join-survey by a team of experts as per necessity before installation of any power infrastructure depending on seismic zone especially it must be made mandatory to set up infrastructure following the building code as per seismic survey.

Before setting up any power infrastructure, nature of land, nature of sand and land structure must be examined by experts properly. Special carefulness must be taken up when installing power infrastructure in the earthquake prone areas especially (greater Chittagong, Sylhet, Mymensingh, Dhaka, Comilla and Bogra) lower sandy areas.

Management and Maintenance of Incumbent Infrastructure

Risky power towers, for example No 1 of Kaptai unit 3, No 7, 14, 926 and 933 towers of the Kaptai-Hathazari and Kaptai-Chandraghona power lines must undergo regular observation by experts and necessary steps must be taken up following their recommendations.
Regular fire fighting and maintenance practices in the power production stations and sub-stations by experts should be made on a mandatory basis.
Anchoring of transformers in the power production stations and sub-stations must be done properly to reduce power crisis due to earthquake-made damage of transformer, snap in the connecting wires or crack in the bushing.
A training program for the manpower working in each and every power production stations and sub-stations must be taken to train them up for pre-quake, after-quake and during the quake activities.

Future Tasks to be Done

There must be a stock of accessories, high voltage bush, anchor support and roving generator etc. to tackle any earthquake related sudden disaster on urgent basis for the power stations located at earthquake-prone areas of the country.
Steps must be taken according to the recommendations after a survey by experts on identifying nature of the two cracks at the eastern and western sides of the Kaptai dam.
As Kaptai falls under seismic zone III, it must be taken under consideration before making design of installing any new unit here.
Steps must be taken immediately to activate the PGO meter to scale the seepage on Kaptai dam. At the same time all maintenance works in the hydro power station areas must continue.
In a bid to make elaborate examination and observation on Reservoir Induced Seismicity, GPS, seismometer and acceleratometer must be installed on urgent basis in the Kaptai hydropower station.
To reduce losses of earthquake and identify the epicenter, seismometer station and portable seismometer must be installed at the proposed sites.
Code of Practice IEEE 693 & ASCE Power Guide Schiff, 1999, which is widely used across the globe, can be used to avert losses in the power station due to earthquake.

The committee in its report also described power infrastructure losses that took place due to earthquake in different countries of the world. It also narrated various losses made in country's power infrastructure due to quake in the year 2003.
The report said the earthquake that took place on July 27, 2003, did not make any loss for the Raujan power station. But the powerhouse, established in 1997, received a 60 centimeter long and one centimeter wide crack on a corner of its floor. However, none of the units in this centre was closed during the quake. This station was made turning a hill into plainland. In geological consideration, the committee thinks that this station may receive problems like crack.
The Shikolbaha Power Station was installed filling soil to 4-5 meters beside Karnaphuli river. So far, this station did not face any problem with the quakes that already taken place. But in geological consideration, earthquake may cause liquefaction problem.
After visiting the Kaptai Power Station, the committee in its report said the main dam has been erected on stable and strong base and there is no mark of any damaging crack at 10 kilometers northern side of the dam. There are two cracks at the southeastern and western side of the dam and its spillway. All installations of the hydropower station has been G 0.1. This area is earthquake-prone considering its seismicity. Despite no crack was found on the dam following the July 27, 2003 earthquake, a crack was found at a school building, which is a kilometer away from the spillway. However, the power station has been producing normally. But the No. 1 tower of the Unit III of the station is situated at a risky slope.
The committee also visited base power generation centre --Ghorashal (950 MW) and Ashuganj (724 MW) power stations. A number of quakes shook the area with 3.6 to 4.5 magnitude of Richter scale. But those could not make any problem for the stations and production was continuing. Both the stations were erected at lower land after filling 4-5 meter with soil. The committee thinks that liquefaction problem may arise here during further quake.
Modunaghat power sub-station, situated beside Halda river in Chittagong faced losses during the 2003 earthquake. The electric wires were jiggling. At one stage, 65-ton transformer including oil moved a six inches southern side at first and then three inches northern side with a big bang. The transformer bushing burst out and the connecting wire damaged. Oil leaked out of it and at last power supply from the sub-station stopped. The report, quoting PGCB, said the incident brought a Tk 2.80 lakh loss. As experts said, this sub-station might face liquefaction problem.
The committee visited Chandraghona and Hathazari power sub-stations and some towers. They suggested for transformer anchoring properly in each and every sub-stations.
The report draw pictures of some countries of the world on how much losses took place in their power sector due to earthquakes. It said, despite the epicenter of earthquake in 1999 in Taiwan was far away from Taipei, foundation of power transfer lines and land slide damaged 11 towers totally and made partial damage to 100 towers throwing Taipei into darkness for a long time.
The whole of Gujarat in India was seriously destroyed on January 26, 2001. This quake could not make any damage Panandro's coal-based power station and two stations in Ahmedabad, which are 180 kilometers away from epicenter of the quake. However, control building of at least 12 sub-stations of Bhuj and Anjar areas were totally destroyed. Partial damages were made in 45 sub-stations. As a result, power supply began after taking a long time.
In Turkey, a transformer jolted in Adapajari sub-station during a quake, porcelain objects burst out and bushing broke up throwing the whole Ankara into darkness. Losses, which occurred due to building collapse on supply line, were minimum and many sub-stations did not face any problem due to good anchoring system. It took 12 days to restart the power system.
The report said, all precautionary measures have now been taken in all developed as well as developing countries considering earthquake risk factors when installing power infrastructure. But, this aspect seems not given due importance in Bangladesh.
When the report was submitted to the State Minister for Power, he admitted the fact saying: “We are to remain busy always for maintenance and expansion of existing power infrastructure. There is no scope for taking initiative regarding disaster security.” He however said as the national committee has recommended on the matter, it is urgent to take initiative to implement that. He said all initiative would be taken to implement the recommendations to prepare the power infrastructure to cope up with disaster, especially the earthquake.