What did the November 2021 order require of pumped storage and battery projects to get the inter-state transmission system waiver?
The Ministry of Power order of 23 November 2021 gave pumped storage plants and battery energy storage systems commissioned up to 30 June 2025 the inter-state transmission system (ISTS) waiver if at least 51% of their annual pumping or charging electricity came from solar or wind. It ran 25 years for pumped storage and 12 years for batteries.
The conditions in the 23 November 2021 order
- Applied to solar, wind, hydro pumped storage plant (PSP) and battery energy storage system (BESS) projects commissioned up to 30.06.2025.
- Solar or wind electricity used by PSP and BESS projects is covered if at least 51% of the annual electricity needed for pumping water, or for charging the battery, is met by solar or wind generation.
- Electricity generated or supplied from such PSP and BESS plants is covered.
- Trading of that electricity in the Green Term Ahead Market and the Green Day Ahead Market is covered up to 30.06.2025.
- Waiver period: 25 years for solar, wind and hydro PSP, or 12 years for BESS, from the date of commissioning.
- PSP and BESS commissioned after 30.06.2025 follow the taper: 25% from 01.07.2025 to 30.06.2026, 50% to 30.06.2027, 75% to 30.06.2028, 100% from 01.07.2028.
What later orders changed
- 29 May 2023: the PSP waiver is tied to award of construction work instead of commissioning, and drawee entities contracting from storage must draw at least 51% of the annual energy as renewable.
- The 10 June 2025 order and the co-located battery rules are covered on the battery storage page linked below.
Our reading of how they fit
The 2025 order says it partly amends the earlier orders. For a battery that is not co-located, it points back to the earlier orders, which on our reading means the 2021 taper and 12 years still apply. The 2025 order does not spell this out, so confirm it before you rely on it.
The 51% charging test for a battery
- Electricity used to charge the battery in a year: 20,000 megawatt hours
- Minimum from solar or wind: 20,000 x 0.51 = 10,200 megawatt hours
- From solar or wind: 9,800 megawatt hours, which is below 10,200, so the condition is not met on these figures
The volumes are an example. The 51% test is the 2021 order's.
What Senseible does here
Senseible reads your electricity bills and fuel invoices into dated records, so the units on your bills are on file. It does not read transmission orders or tell you which waiver band a project falls in; that comes from the developer's commissioning and award dates.
- Battery storage transmission waiver to 2028
- Transmission waiver orders by date
- Battery storage viability gap funding
- Emissions calculators
Sources: Ministry of Power, orders on waiver of inter-state transmission charges, 2020 to 2025 (compiled PDF)
Last reviewed 2026-11-06. Read from the image pages of the 23 November 2021 order and the 10 June 2025 order, and the text of the 29 May 2023 order, in the compiled PDF, on 6 November 2026. The 2021 conditions may have been changed by later orders; the reading of how the 2025 order fits is marked as our own.