Solar, storage and hybrid plants for industry, with the switchboards built in our own works.
Free tool for HT industrial consumers
Demand charge calculator
Enter your contract demand, the maximum demand recorded on your bill and the demand charge rate. See what the DISCOM bills you for demand today, how much a battery that shaves your peak would save every month, the storage size it takes, and the payback on demand charges alone. Runs in your browser; nothing is uploaded.
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Your numbers
Enter the maximum demand and the demand charge rate to begin.
—demand the DISCOM bills you for
—demand charge per month today
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 demand charges work, and why a battery lowers them
What you are billed for
The DISCOM records your kVA in every 15 or 30-minute window of the month and bills the highest one, whether you drew it for one window or every day. On Gujarat HT tariffs there is also a floor: you pay for at least a set share of your contract demand even if you never reached it, and anything above contract demand is billed at a penalty rate.
How peak shaving changes the number
The EMS watches your import. When it approaches the target, the battery discharges to cover the difference, so the meter never records the peak. The battery recharges once the peak passes, usually overnight at the cheapest tariff or from solar surplus at midday. The DISCOM sees a flatter plant, and the demand charge falls every month, whether or not the grid ever trips.
What the calculator assumes
- Your peak lasts the hours you enter every working day; the battery is sized to carry the shaved kVA for that long with margin for depth of discharge and losses.
- Savings stop at the billing floor. If your target falls below it, the contract demand itself has to be renegotiated with the DISCOM, which we can help with.
- The installed cost per kWh includes racks, PCS, switchboard, EMS and installation at 2026 indicative prices.
The feasibility study replaces the hours and percentages with a twelve-month load profile and sizes the battery to it.
Why is my billed demand higher than my recorded demand?
Because of the billing floor. Gujarat HT tariffs bill at least a fixed share of contract demand, typically 85 per cent, even in a month when you drew less. If that happens often, the contract demand is too high and should be revised.
Can I just reduce my contract demand instead of buying a battery?
If your recorded demand is consistently well below contract, yes, and the calculator flags it. A battery is for the opposite case: recorded demand near or above contract because of short peaks that are expensive to pay for all month.
How big a battery does peak shaving need?
Usually smaller than people expect. A 1,500 kVA plant shaving 20 per cent for a two-hour peak needs roughly 300 kW and 700 kWh, which is a single containerised system. The same battery then replaces DG running and rides through trips at no extra capex.
