Solar panel ROI calculator
Calculate payback period, lifetime savings, annual ROI, and CO2 offset for your solar installation. Supports residential and commercial systems across multiple countries.
System details
Electricity & financial
Payback period
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Enter your details to calculate
Daily generation
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Annual generation
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Year 1 savings
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Lifetime savings
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Net profit
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Annual ROI
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Total ROI
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Net cost (after subsidy)
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CO2 offset: —
Equivalent to planting — trees/year
Cumulative savings vs investment over time
Cumulative savings
Investment cost
Year-by-year breakdown
Understanding solar panel ROI
Solar panel ROI is calculated by comparing total lifetime savings from electricity generation against initial installation cost and ongoing maintenance. Unlike most investments, solar ROI improves over time as electricity tariffs rise and the system continues generating free electricity well past its payback period.
Key factors that affect solar ROI
Peak sun hours are the single biggest variable — a system in Pakistan (5–6 hrs/day) generates far more than the same system in northern Europe (2–3 hrs/day). Local electricity tariffs, available subsidies, and net metering availability also significantly impact returns. Panel degradation (typically 0.5% per year) slightly reduces output over time but has minimal impact on overall ROI.
Solar potential by country
| Country | Avg sun hours | Typical tariff | Avg payback | Net metering |
|---|---|---|---|---|
| Pakistan | 5.0–6.0 | PKR 40–70/kWh | 4–7 years | Yes (NEPRA) |
| India | 4.5–6.5 | INR 6–12/kWh | 4–7 years | Yes |
| UAE | 5.5–6.5 | AED 0.23–0.38/kWh | 5–8 years | Yes |
| Saudi Arabia | 5.5–7.0 | SAR 0.18/kWh | 8–12 years | Limited |
| UK | 2.5–3.5 | GBP 0.25–0.35/kWh | 8–12 years | Yes (SEG) |
| USA | 4.0–6.0 | USD 0.12–0.25/kWh | 6–9 years | Yes (most states) |
| Bangladesh | 4.5–5.5 | BDT 8–12/kWh | 5–8 years | Limited |
| Malaysia | 4.5–5.5 | MYR 0.35–0.52/kWh | 6–9 years | Yes (NEM) |
Avoid These Mistakes
Assuming full retail credit for every exported unit
Many net metering and feed-in schemes credit exported electricity below your full retail tariff — this calculator now assumes 70% by default. Check your local scheme's actual export rate rather than assuming 1:1 credit.
Ignoring installer quotes vs. the estimate here
This tool gives a planning estimate. Actual installed cost varies with panel brand, inverter type, roof condition, and local labor rates — always get 2-3 real installer quotes before deciding.
Overlooking maintenance and inverter replacement
Inverters typically need replacement once within a 25-year system lifespan, at a real cost. Make sure your maintenance cost input reflects this, not just annual cleaning.
Comparing payback period alone across systems
A shorter payback isn't automatically the better deal — check total lifetime savings and ROI together, since a slightly longer payback can still produce far more total value over 25 years.
References
🇵🇰 NEPRA (Pakistan)
Pakistan's National Electric Power Regulatory Authority publishes current net metering rules and electricity tariffs used as the basis for the Pakistan presets.
🇬🇧 Ofgem / Smart Export Guarantee (UK)
The UK's SEG scheme sets export payment rules for UK installations — rates vary by supplier and are set independently of the standard electricity tariff.
📄 Your local installer / utility
Actual system costs, subsidies, and net metering export rates are set locally and change over time — confirm current figures with a licensed installer or your utility before relying on any preset or default value shown here.
Frequently asked questions
The average payback period ranges from 5 to 12 years depending on system cost, electricity rates, daily sunlight hours, and subsidies. In Pakistan and India with high electricity tariffs and good sun exposure, payback can be as short as 4–6 years. After payback, the system generates essentially free electricity for the remaining lifespan.
A good solar ROI is typically 10–20% per year, better than most fixed-income investments. Over a 25-year lifespan, most residential installations return 2–4 times the initial investment in electricity savings. ROI improves further as electricity tariffs rise.
A 5kW on-grid solar system in Pakistan typically costs PKR 700,000 to PKR 1,200,000 depending on panel brand and inverter type. With current NEPRA electricity rates, most 5kW systems achieve payback in 4–7 years.
Divide your daily electricity consumption (kWh) by peak sun hours in your area, then add 20% for system losses. A home using 20 kWh/day in Pakistan (5 peak sun hours) needs 4.8 kW, or approximately 10–12 panels of 400W each.
Net metering lets you export excess solar electricity to the grid and receive credit on your bill. This significantly improves ROI by monetizing energy you cannot use immediately. Pakistan, India, UAE, and most developed countries support net metering for residential installations.
On average, 1 kWh of solar electricity offsets approximately 0.5 kg of CO2. A 5kW system generating 25 kWh/day offsets roughly 4–5 tonnes of CO2 per year, equivalent to planting 180–220 trees annually.