What changed, and for whom
Under the amended Electricity (Rights of Consumers) Rules, ToD pricing applies to commercial and industrial consumers with demand above 10 kW from April 2024, extending to most other non-agricultural consumers thereafter. State commissions set the exact windows and percentages, but the national frame is:
- Solar hours (roughly eight daytime hours, state-specified): tariff 10–20% below the normal rate.
- Peak hours (typically evening): tariff 10–20% above the normal rate.
The result is a spread of up to ~40% between the cheapest and most expensive units you buy in a single day.
Why this rewrites C&I energy economics
Before ToD, when you consumed hardly mattered; now it is the bill’s biggest lever. A factory running its heaviest loads into the evening peak pays a structural premium every single day. Options:
- Shift the load — often operationally impossible.
- Generate on-site — solar helps, but it produces in the cheap window, not the expensive one.
- Store — buy or self-generate in the discounted window, discharge in the premium window. This is the only option that works without touching operations.
The arithmetic of one battery, one day
Take a 1 MWh battery cycling once daily on a ₹4/kWh peak-to-cheap spread: 1,000 kWh × ₹4 × ~330 effective cycles ≈ ₹13 lakh a year from arbitrage alone — before counting demand-charge reduction or backup value. The same battery also removes evening-peak exposure that will likely widen as states tune ToD percentages upward.
What we recommend checking on your bill
- Your state’s peak and solar-hour windows and percentages (they differ meaningfully).
- Your consumption profile across those windows (interval data if you have a smart meter).
- Your demand charges — ToD savings stack on top of peak shaving.
Run your numbers in our BESS savings calculator, or send us a bill and we will model it properly.