Note4Students

From UPSC perspective, the following things are important :

Prelims level: Subansiri Lower Hydroelectric Project (SLHEP)

Mains level: Hydropower in India

subansiri

Central Idea

Trial runs for the Subansiri Lower Hydroelectric Project (SLHEP): NHPC Limited, a government of India enterprise, will begin trial runs for the Project in July.
India’s largest: After a delay of 20 years, India is finally approaching the launch of India’s largest hydropower project which is crucial for the region’s energy transition.
About NHPC Ltd: NHPC Limited, formerly known as National Hydroelectric Power Corporation Ltd, is the largest hydropower development organization in India.

About Subansiri Lower Hydroelectric Project (SLHEP)

Gravity dam: It is a concrete gravity dam 116 m high from river bed level on the Subansiri River.
Location: The dam is located approximately 2.3 km upstream of the Subansiri River in Arunachal Pradesh, India.
Accessibility: The project is located near North Lakhimpur on the border of Arunachal Pradesh and Assam. The nearest railhead is Nagaon, and the nearest airport is Lilabari/Dibrugarh.
Run-of-the-river project: NHPC Limited, the project developer, describes the SLHEP as a run-of-the-river project, indicating its design aims to maintain the natural flow of the river.
Power generation capacity: Once completed, the SLHEP is expected to have a power generation capacity of 2,000 MW, making it one of the largest hydroelectric projects in India.

Construction challenges

Natural obstacles: The project has faced several challenges during its construction, including issues related to landslides, the need for redesigning certain aspects, and opposition from various stakeholders.
Delayed completion: Originally scheduled for completion in 2018, the project has experienced delays, contributing to its ongoing construction status.
Clearance from NGT: The SLHEP received clearance from the National Green Tribunal (NGT) on July 31, 2019, allowing for the resumption of main dam construction activities on October 15, 2019.
Construction progress: As of early 2019, work on the SLHEP and other major dam projects in the Assam region, such as the Dibang Dam, had faced challenges and were not progressing as expected.

Cascade development and flood moderation: It is expected to moderate floods in the Subansiri River and bring overall development to the area, benefiting the local economy.
Hydropower boost: Hydropower plays a crucial role in balancing the electricity grid, especially as solar and wind power generation rise.

Its strategic significance is heightened by its proximity to the India-China border.
Located in Arunachal Pradesh, which shares a border with China, the project holds geopolitical importance.