Feasibility study on power grid synchoronisation at 22okv to be finalised
Published: November 16, 2016 8:17 am On: Business
Nepal Electricity Authority (NEA)’s plan to end load-shedding in Kathmandu may
be realised this winter if Nepal-India power grid synchronisation study being commissioned by the Indo-Nepal joint operation committee gives positive results. The joint committee is aabout to finalise the study on synchronisation of Indian grid with Nepali grid at 220kV level through which power imported from the southern neighbour can be brought to Kathmandu, according to Prabal Adhikari, chief of Power Trade Department and spokesperson for NEA. A study related to grid synchronisation at 132kV level has been completed with positive result, informed Adhikari. “However, study 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.”
The joint team has been conducting study at 220kV level so that more power can be brought to Kathmandu to cater to the electricity demand of the major load centre. “After the study is concluded, all the safety measures an be installed within a month to bring power to Kathmandu,” according to Adhikari. If the grid synchronisation plan succeeds, NEA is planning to dispatch 70MW of imported power to Kathmandu through Kulekhani-Hetauda transmission line to Syuchatar (Kathmandu) to realise its plan to end the rolling blackouts plaguing the Valley. According to NEA, peak load of Kathmandu Valley hovers at around 315MW and in off-peak hour demand is less than 200MW. At present, NEA is operating Kulekhani Hydroelectric Project — a reservoir project — in full capacity of 92MW for around one-and-a-half hours a day during peak hours.
Kulekhani and 14.4MW thermal plant of Hetauda are actually backup supply system of the NEA and Kulekhani used to be operated only during peak hours from mid-January in the previous years as supply from the run-of-river (RoR) based aprojects declines to only one-third of their installed capacity. NEA officials claim that Kulekhani plant can generate 92 MW if it is operated at full fledged capacity for four hours a day and would be in operation for four months.
While the country has been importing around 250MW of electricity from India, it cannot be supplied to the Valley due to lack of necessary infrastructure, including grid synchronisation. This means if the grid synchronisation plan is not materialised, unfortunately Kathmanduites may not have seen the last of rolling blackouts of up to 16 hours a day. This is because majority of the projects in the country are of RoR type, which means their power generation drops sharply during winter months. The 50MW Upper Marsyangdi A hydroelectric project started commissioning power since last month, but then, 45MW Bhotekoshi Hydropower project has been shut down after it suffered damages due to floods in July. Hence, the generation capacity of the country is actually stagnant when compared to previous year. “Even if the grid synchronisation plan does not materialise, NEA will try to minimise the load-shedding hours by making the distribution system robust,” assured Adhikari.