Lanka takes over Norochcholai plant
Disna MUDALIGE
The Ceylon Electricity Board (CEB), stepping forward in the mission
to supply electricity to all, took over the administrative and
operational work of the Lak Vijaya Coal Power Plant in Norochcholai from
the Chinese main contractor China National Machinery and Equipment
Import and Export Corporation recently.
The commissioning of Lak Vijaya power house was a milestone in the
drive to make Sri Lanka the energy hub of the region. Being the first
coal fired power plant in the country, the entire system of operation
has been a novel experience to the Sri Lankan engineers and workers.
After receiving first hand training on the administrative and
operational activities from the Chinese, the CEB now operates 90 percent
of the work in the power house. Joint operations with the Chinese will
continue for another four weeks aiming for a smooth transition.
National grid gets 900 megawatts
Lak Vijaya adds 300 megawatts to the national grid under the first
phase of the project. Another 600 megawatts to be generated from the
plant after the completion of the second phase, lifting the total power
generation capacity to 900 megawatts.
According to the Ministry calculations, the present power demand of
the island is about 2500MW and it can rise up to 2800 megawatts in the
near future. In this light, Norochcholai power house was a long awaited
and long overdue project which had to be in the development queue
awaiting the green light for commencement.
The idea of coal power plant in Norochcholai can be traced back to
1990s but it was repeatedly postponed due to discrepancies with the
environmentalists.
However, balancing both development and environment efficiently, Lak
Vijaya had been planned keeping in line with all environmental norms and
international environmental standards.
Track of the project
CEB Chairman Prof Wimaladarma Abeywickrama explaining the progress of
the project said the first phase of the contract was completed on
February 13, 2011, which is 11 months ahead of the scheduled time. The
contract started in July 23, 2007 for a period of 57 months.
The Sri Lankan government had spent Rs 5300 million for the first
phase and the Chinese company had provided USD 455million at two percent
reduced interest rates. President Mahinda Rajapaksa opened the plant on
March 22, 2011.
The first phase also included a transmission line of 117 kilometres
in length to Veyangoda grid substation, and from there the power has
been added to the national grid. The contribution of 2200 Chinese
workers and about 800 local labourers had been received during this
phase.
The resettlement of 80 families in newly constructed alternative
houses with all amenities and infrastructure facilities, and renovation
of roads had also taken place with the launch of the project.
The contribution of Sri Lankan government for the second phase will
amount to about Rs 8000 million while US$ 891 million will be
provisioned through a Chinese loan at reduced interest rates.
A transmission line to Anuradhapura will also be built under this
phase.
The Chairman also observed that since the unit price of coal is still
comparatively low, Lak Vijaya will enable the CEB to provide electricity
at internationally competitive prices even after adding freight charges.
Coal importation
Lak Vijaya Coal Power Plant Deputy General Manager Saliya
Panditharatne explained that only quality coal consignments had been
imported to the country concerning environmental impacts.
Presently those consignments are being imported from Indonesia under
a three-year agreement. The coal is unloaded mid-sea and transported
through barges to the jetty.
Then the coal is being inserted into a 500m long conveyor belt to
transport those loads to the coal yard that has the capacity to store
about 0.8million tonnes of coal. A wind barrier was built on the sides
of the coal yard to prevent coal dust being dispersed to villages with
the wind.
He observed that a coal consignment imported at a time is carrying
about 75,000 tonnes. He also revealed that another two shipments would
be brought into the country shortly.
"When the power house generates 300 megawatts it consumes 114 tonnes
of coal per hour. About 12 tonnes of coal ash is gathered per hour as a
result of this process. Several cement companies have already made
agreements to buy fly ash from us." he noted.
Technical outlook
A painstaking complicated technical process applies from the initial
step of coal insertion to the ultimate result of illuminating a bulb.
The power plant uses auto diesel when starting and finishing off. The
plant gradually shifts to coal combustion and operates entirely from
coal thereafter.
The coal is pulverized before inserted into the burner.
Then a turbine operates using the steam coming out and as a result
power is generated through generators. Most of these technologies and
equipment are being utilized in Sri Lanka for the first time.
Sea water is being used after a desalination process for cooling
purpose since ground water resources cannot be used for this purpose.
Panditharatne said that they release clean water back to the sea after
ensuring the temperature of the water is not more than seven Celsius
degrees of the normal sea water temperature.
"Presently the temperature of this water is just above five degrees
of the normal sea water. We strictly adhere to this standard to avoid
any environmental concern. This water regains the normal temperature
within a 150m sea area", he explained.
Flue gas goes through a process of desulphurization while more
options are added to prevent producing certain harmful gases.
Panditharatne reiterated that the smoke released to the air is minimal
and does not contain harmful gases. "Only the steam which is harmless is
being emitted largely to the air," he said.
Operational activities
The generation of power from this plant had been temporarily stopped
five days during the Sinhala Hindu New Year since the demand is low. "If
the demand is lower than 90 megawatts it cannot be operated from coal.
Therefore we decided to suspend the power generation during this period.
Then again on May 20 we had to close the plant for maintenance work
and recommenced on June 4. Then a technical problem occurred on June 7
and we could rectify it and resume work after July 10.
"We have been generating power from the plant since then without any
interruption. Occurrence of technical problems during the first year of
commissioning is normal since we carry out various tests. However we
have also signed an agreement of defect liability period with the
contractor keeping this in mind." the CEB Chairman noted.
He also pointed out that operating the plant in its full capacity
when it is turned on is good for the maintenance of a coal power plant.
"In this manner we will be able to supply power from this plant without
any problem in the next 20 years," he observed.
|