CTU has been assigned the responsibility of undertaking transmission of electricity through Inter State Transmission System (ISTS) and discharge all functions of planning and coordination under section 38 of Electricity Act, 2003.

Planning studies are undertaken for identification of new ISTS for evacuation of power from generation pockets to the load centres, augmentation/reconfiguration of existing system etc. in coordination with concerned agencies based on load & generation capacity addition program, connectivity / open access application, feedback from the grid operators, National Electricity Plan by CEA etc. The schemes are deliberated in monthly consultation meetings with CEA, Grid-India, STUs and other stakeholders. The agreed schemes are taken up with NCT/RPC/MoP for recommendations/ approval and thereon for implementation through RTM or TBCB route by TSPs.

Planning of cross border interconnections with neighbouring countries like Bhutan, Nepal, Bangladesh, Sri Lanka, Myanmar etc. are also carried out in consultation with the counterparts of respective countries.

CTU is also mandated to draw up plan for ISTS for upto next five years on rolling basis every year in consultation with various stakeholders. Accordingly, ISTS Planning Procedure has been prepared. The entire process for transmission planning is undertaken on continuous basis, involving two cycles i.e. from April to September and October to March. Thus, ISTS Rolling plan reports are brought out by CTU on half-yearly basis in the months of September (interim report) and March (final report) in every financial year.