Nepal | September 30, 2020

Lack of grid synchronisation affects power supply in Valley

Pushpa Raj Acharya
Share Now:

Kathmandu, March 8

Lack of proper protection system in Nepal-India power grids for electricity trade has been causing repeated technical glitches in the central grid.

As Khimti-Dhalkebar transmission tower started tripping on Tuesday night, power supply to the central grid was affected and it took around an hour to recover supply.

Until Nepal Electricity Authority (NEA) installs all required protection measures, which is called power grid synchronisation, more of such technical glitches can be expected in the coming days whenever big consumers (industries) stop using power and there is suddenly high current flow to the central grid.

Currently, NEA has been bringing imported power to Kathmandu via Dhalkebar-Khimti transmission line without carrying out grid synchronisation between the power grids of India and Nepal. The repeated technical glitches in the central grid due to lack of proper protection system has posed a risk of the central grid collapsing.

Nepal has been importing 145 megawatts of electricity through Muzaffarpur (India) to Dhalkebar (Nepal) cross-border transmission line. A large chunk of the imported electricity is being supplied to Kathmandu and when the problem occurs in Dhalkebar-Khimti transmission towers the whole power supply system in the central grid gets affected.

As per its plan to end load-shedding, NEA started bringing imported power to Kathmandu after completion of Khimti-Dhalkebar transmission line. However, the power utility overlooked the possible risks like system failure due to lack of grid synchronisation.

The Nepal-India joint committee has already finalised study on grid synchronisation at 220 kV level, which has suggested the need to install df/dt relay (a special system used to identify abnormal changes in frequency and take remedial actions to prevent overload and the resulting blackout) and direct communication system between Dhalkebar Substation and load dispatch centre of Nepal.

However, the 220 kV substation in Dhalkebar is yet to be completed. According to NEA officials, it will take another three months for the Dhalkebar substation to be completed. “Without completion of 220 kV substations, we cannot carry out power grid synchronisation as recommended by the joint study team,” one high level official at NEA told The Himalayan Times on condition of anonymity.

Though it will take several months before the grid synchronisation process can be carried out, the power-starved NEA decided to bring imported electricity to Kathmandu by installing only normal protection measures within a short period of time to end the rolling blackouts of Kathmandu Valley from this dry season (December to May).

NEA officials have said that the grid synchronisation will be conducted during wet season when country itself has sufficient power as generation of run-of-the-river (RoR) projects increases.


Additional 100 MW to be imported

KATHMANDU: Following the transmission line upgradation of Kataiya-Kusaha and Raxaul-Parwanipur transmission line, Nepal Electricity Authority (NEA) is preparing to import additional 50 megawatts electricity from each for this dry season (till May or June).

The power utility has proposed NTPC Vidyut Vyapar Nigam Ltd (NVVN) to sign power purchase agreement for up to 100 MW more. NVVN is the nodal agency appointed by Indian government for cross-border electricity trade. Currently, NEA is importing 130 MW from Kataiya-Kusaha and 10 MW from Raxaul-Parwanipur. “We have written to NVVN and negotiations will be held soon,” said Prabal Adhikari, chief of Power Trade Department of NEA. “We are trying to import 100 MW additional power by this dry season.”


A version of this article appears in print on March 09, 2017 of The Himalayan Times.


Follow The Himalayan Times on Twitter and Facebook

Recommended Stories:

More from The Himalayan Times:

Six student leaders arrested for staging protest outside Chinese Embassy in Kathmandu

KATHMANDU, SEPTEMBER 28 Six student leaders of Nepal Student Union, the student wing of major opposition Nepali Congress, were arrested today for staging a protest outside the Chinese Embassy at Baluwatar against the alleged border encroachment by the Chinese side in Humla district. The NSU le Read More...

Woman found dead in Saptari district

A police team has been deployed from Province Police Office, Janakpur, to investigate the case RAJBIRAJ, SEPTEMBER 28 A 50-year-old woman was found dead at Mayanakaderi village, Ward No 2 of Tirhut Rural Municipality, Saptari, yesterday. The body of Dayaman Devi, wife of local Shiv Narayan, w Read More...

TU likely to conduct exams after Dashain, Tihar festivals

KATHMANDU, SEPTEMBER 28 Tribhuvan University has decided to conduct its regular examinations after the upcoming festivals by adding more examination centres and allowing students to take exams from the nearest examination centres. TU is all set to publish the exam routine very soon. The cou Read More...

Dr KC’s supporters move NHRC against CDO, police chief

KATHMANDU, SEPTEMBER 28 Supporters of Dr Govinda KC have filed a complaint with the National Human Right Commission against Kathmandu’s Chief District Officer Janak Raj Dahal and head of Metropolitan Police Range’s SSP Shyam Lal Gyawali. Members of ‘solidarity for Govinda KC’ filed the Read More...

Sanphe-Martadi road obstructed for months

BAJURA, SEPTEMBER 28 Sanphe-Martadi road section has been obstructed for the last three months due to landslides in different places along the road section in Bajura. The road section from Barjugard to Martadi was obstructed due to incessant rainfall following mud slips in many places. The Read More...

THT logo

KTM 390 Adventure rolls out in Nepal

KATHMANDU: KTM, the world’s number one and Nepal’s fastest growing premium motorcycle brand, has launched the most awaited KTM 390 Adventure in the country. The bike can be bought at KTM showrooms across the country for the introductory price of Rs 999,000, as per a media release. KTM 390 Advent Read More...

NAC holds discussions to get ground-handling permission at GBIA

KATHMANDU, SEPTEMBER 28 Nepal Airlines Corporation (NAC) is preparing to provide ground-handing services at Gautam Buddha International Airport (GBIA), which is nearing completion. As GBIA has mentioned that it will be ready within the next six months, NAC has proceeded to get the permission to p Read More...

THT logo

NMB Bank joins PCAF

KATHMANDU: NMB Bank has joined the Partnership for Carbon Accounting Financials (PCAF), an industry-led initiative to measure and disclose greenhouse gas emissions financed by loans and investments. PCAF has grown rapidly, as per a press statement. From 50 financial institutions with over $5 tril Read More...