Reduce Your Capacity Tariff with a Battery
The Fluvius capacity tariff costs €49.05 per kW per year (2026 tariff). A battery that reduces your monthly peak by 50 kW saves you €2,453 per year, year after year. Calculate your savings below.
What Is the Capacity Tariff?
Since January 2023, every Flemish grid user pays a capacity tariff. This tariff is not based on how much you consume, but on how sharp your peaks are.
Each month, Fluvius measures your highest 15-minute quarter-hour peak. Those twelve monthly peaks are averaged to produce your billing peak. The higher that billing peak, the more you pay.
The minimum is 2.5 kW. But a joinery with heavy machinery, a fruit farm with cold storage or a potato store with drying processes quickly peaks at 100, 200 or 300+ kW. And pays accordingly.
Whoever loads the grid heavily, pays more. It is that simple. A battery that shaves peaks lowers your billing peak, and therefore your capacity tariff.
Calculate Your Savings
Enter your current monthly peak and see immediately how much a battery saves on the capacity tariff.
How Does a Battery Reduce Your Peak?
The InduBa EMS continuously monitors your consumption at 15-minute intervals. As soon as power rises towards your target, the battery discharges to absorb the difference. The result: the grid never sees your actual peak.
1. Monitor
GridShield measures the current power every second.
2. Predict
The EMS predicts whether the quarter-hour will exceed the target.
3. Discharge
The battery discharges exactly enough kW to shave the peak.
4. Charge
During low load or cheap EPEX hours the battery recharges.
What Determines Your Capacity Tariff?
| Term | Explanation |
|---|---|
| Quarter-hour peak | Highest 15-minute average power in a month |
| Monthly peak | The highest quarter-hour peak of that month |
| Billing peak | Average of 12 monthly peaks over the billing period |
| Minimum contribution | 2.5 kW, everyone pays this minimum |
| 2026 tariff | On average €49.05/kW/year (varies by grid operator) |
The capacity tariff in Flanders is based on the highest 15-minute quarter-hour peak per month, averaged over 12 months. A battery that shaves these peaks can structurally reduce the grid tariff.
Save on your capacity tariff
We simulate your actual consumption peaks and calculate the exact savings, quarter-hour by quarter-hour, on real data.