How to Calculate Solar Panel ROI

What is Solar Panel ROI?

A solar ROI calculator determines payback period and long-term return. Typical payback: 6–10 years UK; 5–8 years in sunnier US states. Panels last 25–30 years.

Formula

ROI (%) = (Lifetime savings / System cost) × 100 | Payback period (years) = System cost / Annual savings

Step-by-Step Guide

1Payback = Net cost / Annual electricity savings
2Long-term ROI = (Total savings − Net cost) / Net cost × 100
3Factor in rising electricity prices over time
4Export tariff (Smart Export Guarantee UK) adds extra revenue

Worked Examples

Input

£7,500 system, £1,200/yr savings

Result

Payback = 6.25 years; 25yr return ≈ £22,500 on £7,500 → 200% ROI

Frequently Asked Questions

What is Solar Roi?

A solar ROI calculator determines payback period and long-term return. Typical payback: 6–10 years UK; 5–8 years in sunnier US states

How accurate is the Solar Roi calculator?

The calculator uses the standard published formula for solar roi. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Solar Roi calculator use?

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Solar Roi calculator use?

The core formula is: Payback = Net cost / Annual electricity savings. Each step in the calculation is shown so you can verify the result manually.

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