Development of Power Transmission System Interconnections in South-Asian Region

In today's world, electricity is central to the various socio-economic developmental activities being carried out worldwide, as transportation of electrical energy is economical compared to physical transportation of energy resources to the point of consumption. The various energy resources used for generation of electricity are generally non-uniformly distributed. This necessitates development of efficient and economic transmission infrastructure connecting the energy generation sources and large power demand centres, for supply of reliable and secure power to the end user.

The Indian electricity grid is divided into five regional grids namely, Northern, Eastern, North-Eastern, Western, and Southern for better management. Generally, Eastern, North-Eastern, and Western grids are surplus in energy, whereas Northern and Southern grids are deficit. The regional grids have been progressively connected through various high capacity HVDC and EHVAC links to form a National Grid so as to share the regional energy resources and bring economy and efficiency in system development as well as operation at national level.

India has started large scale deployment of Renewable Energy (RE) based generation projects so as to bring down the Carbon footprint. The Solar potential of India is estimated to be about 750GW and Wind potential is about 300GW (100m hub height). The country envisages to have installed RE capacity of 175GW by 2022. The neighbouring countries of India like Nepal, Bhutan, and Myanmar have large hydro potential, Bangladesh is rich in gas reserves, and Sri Lanka mainly uses conventional resources like coal and gas.

The interconnection of Indian grid with the neighbouring countries comprises of small radial interconnection at lower voltage levels as well as high capacity AC and HVDC Back-to-Back interconnections. The small radial interconnections have been developed over the years primarily to feed the load centres near to international borders on either side. The high capacity interconnections have been developed mainly through joint studies between participating Paris 2020 countries, to meet large scale power transfer requirements to major load centres as well as for evacuation of power from hydro projects.

Presently, the under operation cross-border interconnections between India and its neighbouring countries namely Bangladesh, Bhutan, Nepal, and Myanmar facilitate power transfer to the tune of 3830MW. Interconnections which would enhance this cross-border trade quantum by 2580MW are under various stages of development.

Ministry of Power (MoP), Govt. of India (GoI) has issued Guidelines for “Import/Export (Cross Border) of Electricity-2018” for facilitating import/export of electricity between India and neighbouring countries. Subsequently, in line with the said MoP, GoI Guidelines, Central Electricity Regulatory Commission (CERC) has issued Cross Border Trade of Electricity (CBTE) Regulations, 2019 for facilitating open access in crossborder trade of electricity.

This paper discuss about phase wise development of cross-border interconnections in South-Asian countries, for mutual social and economic benefits. Development of such interconnections among South-Asian nations is expected to help in deployment of large scale environmental friendly RE and Hydro based generation projects, sharing of common balancing resources, sharing of energy resources among interconnected nations resulting in economic operation of power system, development of common electricity market, better Hydro-Thermal-RE mix in the region, and improving region wide reliability and security among others.