The Ministry of Power in India has exempted solar and wind power assets in the country from paying Inter-State Transmission System (ISTS) charges for projects commissioned till June 30, 2025. It will replace the previous deadline of June 30, 2023 (see ISTS Charges Waive Off Period Extended In India, Again).
In an order dated June 21, 2021 issued, the ministry specified that the waiver is allowed for inter-state transmission charges only, and not losses. It comes into effect immediately.
The waive off also applies to hydro pumped storage plants (PSP) and battery energy storage systems (BESS) if these are commissioned up to June 30, 2025, provided at least 70% of annual electricity requirement for pumping water in the PSP or for charging of BESS is met by solar and/or wind system generated electricity.
"The Inter-State Transmission Charges for power generated/supplied from such Hydro PSP and such BESS shall be levied gradually: 25% of the STOA charges for initial 5 years of operation, then charges can be gradually increased in steps of 25% after every 3rd year to reach to 100% of STOA charges from 12th year onwards. This may be aligned with the gradual reduction in tariff and payment of debt," reads the ministry's order.
Waivers of transmission charges shall also be allowed for trading of electricity generated/supplied from solar, wind, PSP and BESS in Green Term Ahead Market (GTAM) and Green Day Ahead Market (GDAM) for 2 years, till June 30, 2023. It will be reviewed on annual basis.
ISTS connectivity is a significant feature for India's renewable energy ambitions as it allows such a transmission system to send electricity between states. The government has been extending the waive-off timeline for solar and wind power generation capacity for quite some time now, from December 31, 2019 to December 31, 2022, then June 30, 2023 and now June 30, 2025 (see ISTS Charges Waive Off Period Extended In India, Again).