Calculate solar panel system size based on your electric bill and location. Compare panel types, estimate installation cost after federal tax credit, project 25-year savings with degradation, and determine payback period.
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Divide your annual kWh usage by your area's peak sun hours × 365 × panel wattage. A home using 10,000 kWh/year in an area with 5 peak sun hours needs roughly 5.5kW, or about 14 panels at 400W each.
Average cost is $2.50-3.50 per watt before incentives. A typical 8kW system costs $20,000-28,000. After the 30% federal ITC tax credit, net cost drops to $14,000-19,600. Many states offer additional rebates.
Typically 6-12 years depending on electricity rates, sun exposure, and incentives. In high-rate states like California, payback can be 5-7 years. After payback, solar provides free electricity for the remaining 15-20 years of panel life.
Using the Solar Panel Calculator is simple: visit the tool page, enter your data or input into the provided fields, and get instant results. No downloads, installations, or sign-ups are required. The tool runs directly in your web browser for maximum convenience.
Yes, the Solar Panel Calculator is 100% free to use with no limitations. There is no registration required, no daily usage caps, and no hidden fees. You can use it as many times as you need.
The Solar Panel Calculator uses industry-standard formulas and algorithms to deliver reliable results. While the tool is designed for accuracy, results should be used as estimates and guidance. For critical decisions, always consult a qualified professional.
Yes, after running your calculation you can copy the results to your clipboard or take a screenshot. The Solar Panel Calculator displays a detailed breakdown so you can easily record or share your numbers. No account is required to use or save results.
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Calculate solar panel system size based on your electric bill and location. Compare panel types, estimate installation cost after federal tax credit, project 25-year savings with degradation, and determine payback period.
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| Item | Cost |
|---|---|
| Monocrystalline Panels (23 x 400W) | $25,760 |
| Inverter(s) | $2,760 |
| Roof-Mounted Mounting | $2,760 |
| Electrical Work | $2,000 |
| Permits & Inspections | $500 |
| Gross Cost | $33,780 |
| Federal Tax Credit (30%) | -$10,134 |
| Net Cost | $23,646 |
| Panel | Watts | $/W | Efficiency | Notes |
|---|---|---|---|---|
| MonocrystallineSelected | 400W | $2.8 | 22% | Highest efficiency, premium look, best for limited space |
| Polycrystalline | 340W | $2.4 | 17% | Good value, slightly lower efficiency, blue tint |
| Thin-Film | 250W | $2 | 12% | Most affordable, flexible, requires more space |