The 400kV Sitamarhi-Motihari transmission line, an important component of the Eastern Region System Strengthening Scheme (ERSS) – XXI, was recently commissioned.
The double-circuit line with triple snowbird conductor spanning 171 ckm and located in Bihar was contracted to Tata Projects, in January 2018.
Officially called “Sitamarhi (New) – Motihari 400kV D/C” line, this is an important constituent of the ERSS-XXI project that is being implemented by Power Grid Corporation of India Ltd, under the tariff-based competitive bidding (TBCB) route. The line with 230 tower locations was scheduled to commission in January 2021 but work progress was severely affected by water logging.
The project is being implemented by “ERSS XXI Transmission Ltd”, a project SPV that was acquired by PGCIL in January 2018.
Overall scheme
The overall transmission scheme includes the following lines:
- 400kV D/C Darbhanga-Sitamarhi (New) [160 ckm]
- 400kV D/C Sitamarhi (New) –Motihari [171 ckm]
- LILO of both circuits of Nabinagar-II – Gaya 400kV D/C (Quad Moose) line of PGCIL at Chandauti (New) [2.9 km]
- LILO of Kishanganj – Patna 400KV D/c (Quad Moose) line of PGCIL at Saharsa (New) [75 km]
(Please note that some lengths are in ckm, while others are in km)
All the four lines were contracted upon Tata Projects, simultaneously, in January 2018. Of the two circuits of Line#1 mentioned above, one circuit was charged on March 31, 2021, and the second is expected to be charged soon. The line is physically complete. Line #2, the subject matter of this news item, was commissioned in April 2021, while Line#3 was commissioned on March 11, 2021. Line #4, running around 75km, is under construction. Of the 211 tower locations, foundations of 209 have been constructed. Towers have been erected on 202 locations while stringing work worth 62 km is so far complete.
Substations
The project also involves three new substations and extension work at two others. One substation has been commissioned on March 11, 2021, while work on the other project components is in advanced stage of completion. The commissioned substation is a new 400/220/132kV installation at Chandauti, contracted upon ABB India in March 2018.
Objective of ERSS XXI
Largely due to segregation of agricultural feeders, power demand in Bihar is likely to cross 11,000 mw by March 2022, up from under 4,000 mw in FY17. ERSS XXI was envisaged to strengthen the interstate transmission system (ISTS) so as to meet the increased power requirement in Bihar. This is being achieved through around 500 ckm of 400kV lines and three new substations, with aggregate capacity of 4,900 MVA, apart from augmentation works at two existing substations. All the project elements are located in Bihar.
(Featured photograph for illustration only)