Preliminary estimate
Estimate your savings
Enter the figures from your electricity bill and your roof area. The calculator runs in your browser and sends nothing unless you press send.
Assumptions and method
- Monthly model, not an hourly simulation. Real figures come only after EMS load metering.
- Yield: PVGIS 5.3 (ERA5 2005–2023), Ninh Binh, 10° tilt facing south, 14% system losses, minus first-year panel degradation.
- Power density from the panel datasheet; 15% of the area deducted for walkways and shading (assumption).
- Savings = solar energy replacing grid power × your average tariff. Time-of-use differences and export revenue are not included.
- Low–high range of ±10% for weather and operation.
- Excludes taxes, special connection costs and maintenance.
Source: PVGIS (JRC) · Updated 2026-10-28