Solar Panel Savings Calculator
Last updated: October 15, 2026
Estimate solar bill savings, net system cost and simple payback period.
Projected savings over analysis period
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- Net system cost: —
- First-year bill savings: —
- Simple payback period: —
On this page
Quick summary: Estimate solar bill savings, net system cost and simple payback period.
Read the method, example and limitations
Updated reference sections in this guide are in English.
Guide language: English. Updated October 15, 2026.
What this calculator estimates
Estimate solar bill savings, net system cost and simple payback period.
Inputs and units
Enter Average monthly electric bill ($), Bill offset from solar (%), Annual utility-rate increase (%), Installed system cost ($), Tax credits and incentives ($), Analysis period (years). Use the units shown. Required fields cannot be blank. Use zero only where that field and the model allow it. Select Calculate after changing the values.
Method and assumptions
First-year modeled savings = monthly electricity bill x 12 x offset percentage / 100. Increase those savings by the entered annual bill-growth percentage each year. Compare cumulative savings with system cost minus incentives, floored at zero.
Worked example
A 100 monthly bill offset by 50% produces 600 first-year savings. At zero annual growth, ten whole years produce 6,000. A zero net upfront cost is reported directly.
Limitations
The estimate does not separately model degradation, maintenance, financing, export tariffs, equipment replacement or incentive eligibility. Whole analysis years must be from 1 to 100. Entered incentives and costs are assumptions, not verified offers.