Solar, storage and hybrid plants for industry, with the switchboards built in our own works.
Free tool for HT consumers on ToD tariffs
Time-of-day tariff calculator
Enter your peak-hour and night-hour units and rates. See the spread a battery can earn by charging at night and discharging in the peak, the battery size that fits your peak units, and the payback from tariff shifting alone.
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Your numbers
Fill in the required figures to begin.
—net spread per shifted unit
—units you can shift per day
Unlock the detailed report
The headline numbers are free. The full breakdown, sizing and payback are emailed to you and unlocked here once you verify your work email.
- Full breakdown of every figure
- System size, capex and payback
- What to do next, flagged by our engineers
- A copy emailed to you, plus one-click request for the free feasibility study
One-time code to your email, nothing else. We do not share your details.
Verified as . The detailed report is below and in your inbox.
How time-of-day shifting pays
The spread
A ToD tariff charges more in the evening peak and less at night. A battery buys units at the night rate, loses about ten per cent in the round trip, and sells them to your own plant in the peak at the peak rate. The spread per unit is the peak rate minus the night rate grossed up for losses. On most Gujarat HT tariffs that spread is two to four rupees a unit.
Why it is rarely the whole case
Shifting alone pays back slowly, because the spread is small and the battery cycles once a day. It becomes attractive when the same battery also cuts demand charges and replaces DG hours, which is how we size storage. Use this tool to see the ToD contribution, then the demand charge and DG tools for the rest.
What is assumed
- One full cycle per working day, with the battery sized to your peak units per day unless you enter a size.
- Losses at the efficiency you set; no degradation or auxiliary load counted.
- Installed cost per kWh includes PCS, switchboard, EMS and installation at 2026 indicative prices.
Does ToD shifting alone justify a battery?
Rarely. A two to four rupee spread cycled once a day pays back in eight to twelve years. Add demand-charge reduction and DG replacement on the same battery and the combined payback is usually four to six years.
Can solar do the shifting instead of the grid at night?
Yes, and it is better. Charging from midday solar surplus costs ₹2.5 to 3.5 a unit, less than the night rate, so the spread is larger. The payback estimator covers that case.
What if my tariff has three slabs?
Enter the two that matter for the battery: the slab it charges in and the slab it discharges in. The normal slab in between does not change the result.
