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Solar calculator
From your power bill to a system size in seconds: panels, roof space, cost, payback and the battery you'd need for backup.
Your home or site
Your estimate
4.5 kWp
- System size4.5 kWp
- Panels10 × 450 W
- Roof area (approx.)21 m²
- Production per year7,542 kWh
- Installed cost (estimate)$4,950
- Savings per year$1,296
- Simple payback3.8 years
- CO₂ avoided per year3 t
- Battery for backup3.7 kWh usable
Assumes 18% system losses, about 2.1 m² per panel and 0.4 kg CO₂ per grid kWh; savings count only the power you would otherwise buy. A planning estimate, not an engineering design: shading, roof angle, local tariffs and incentives change the real numbers.
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