Solar Savings Calculator
Enter the system size in kilowatts, effective sun hours and your price per kWh. The calculator estimates production, monthly savings and the years to recover the investment.
All panels combined. E.g., 14 × 400 W panels ≈ 5.6 kW.
Editable estimate; 4.5–5.5 is typical in PR.
Used for the payback period. Leave 0 if unknown.
Estimated monthly savings
$165.00
750 kWh · Assuming full net metering at your price per kWh.
- Daily production
- 25 kWh
- Yearly production
- 9,125 kWh
- Yearly savings
- $2,007.50
- Payback
- 7.5 years
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About this calculator
How it works
Daily production = system kW × effective sun hours. “Effective hours” already account for clouds, angle and equipment losses; in Puerto Rico a conservative value is typically 4.5–5.5 hours.
Monthly savings = kWh produced × your price per kWh, assuming all production is consumed or credited (net metering).
Payback = system cost ÷ annual savings. It excludes financing and maintenance.
Example
A 5 kW system at 5 effective hours produces about 25 kWh a day — 750 kWh a month. At $0.22 per kWh that's $165 in monthly savings. If the system cost $15,000, payback is about 7.5 years.
Important limitations
- Sun hours are an editable estimate; real production depends on your roof, shade, orientation and weather.
- Savings assume full net metering; credits, LUMA fixed charges and net metering rules can change the outcome.
- Batteries, financing, maintenance and panel degradation (~0.5% per year) are not included.
Learn more
Guides explaining the context behind this calculation.
Frequently asked questions
This calculation runs in your browser and is never sent to a server. Your last values may be saved on your device only, for convenience. Results are estimates and are not financial, tax, accounting or legal advice.