Solar Energy Savings Calculator — Free 2026
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Solar Energy Savings Calculator
Find out if solar panels are worth it — payback period, 25-year savings, and CO₂ offset
↻ Updated 2026 — Includes 30% Federal Tax Credit (IRA)
Enter your solar details
Monthly electric bill ($)
Electricity rate ($/kWh)
System size (kW)
Peak sun hours/day
Recommended system: for your bill. Sun hours: AZ/NV 6.5, CA/TX 5.5, FL/GA 5.0, NC/VA 4.5, NY/MA 4.0, WA/OR 3.5.
Installation cost ($)
US avg: $2.50–$3.50/watt. 8 kW system ≈ $20,000–$28,000 before incentives.
Federal tax credit (%)
IRA guarantees 30% through 2032. Some qualify for 40%+ with adder credits.
BILL COVERAGE
Estimated annual electricity savings
Monthly savings
Annual kWh produced
Federal tax credit (30%)
Net installation cost
Payback period
25-year net profit
Verdict
25-year net profit
Payback period
CO₂ offset per year
25-year ROI
How the Solar Savings Calculator Works
This calculator estimates annual energy production based on your system size, local peak sun hours, and a standard 80% performance ratio. It then applies the 30% federal Investment Tax Credit, accounts for 0.5% annual panel degradation, and models 3% annual utility rate increases to project 25-year returns.
Annual kWh = System kW × Peak Sun Hours × 365 × 0.80 (efficiency)
Annual Savings = Annual kWh × Electricity Rate
Net Cost = Install Cost × (1 − Tax Credit %)
Payback = Net Cost ÷ Annual Savings
Annual Savings = Annual kWh × Electricity Rate
Net Cost = Install Cost × (1 − Tax Credit %)
Payback = Net Cost ÷ Annual Savings
The 25-year projection compounds savings with 0.5% annual panel degradation (industry standard) and 3% annual utility rate increases — the historical US average. This makes the long-run return better than the raw annual savings suggest.
☀️ 30% Federal Tax Credit — The Inflation Reduction Act
The IRA guarantees a 30% Investment Tax Credit (ITC) on residential solar installations through 2032. On a $24,000 system, that is a direct $7,200 reduction in your federal tax bill — not a deduction, a credit. Some systems qualify for additional "adder" credits (domestic content, low-income community) that can push the credit to 40–50%. The credit applies to the full installed cost including labor, permits, and battery storage.
Average Peak Sun Hours by State
Peak sun hours are not daylight hours — they are the equivalent hours of full 1,000 W/m² solar irradiance. Use these when setting your sun hours input.
| State / Region | Peak Sun Hours | Avg Rate ($/kWh) |
|---|---|---|
| Arizona, Nevada, New Mexico | 6.0 – 7.5 | 0.12 – 0.14 |
| California, Colorado | 5.5 – 6.5 | 0.23 – 0.30 |
| Texas, Oklahoma | 5.0 – 6.0 | 0.12 – 0.14 |
| Florida, Georgia, Alabama | 5.0 – 5.5 | 0.12 – 0.15 |
| North Carolina, Virginia | 4.5 – 5.0 | 0.12 – 0.14 |
| New York, New Jersey, CT | 4.0 – 4.5 | 0.20 – 0.27 |
| Massachusetts, Vermont, ME | 4.0 – 4.5 | 0.23 – 0.32 |
| Illinois, Ohio, Michigan | 4.0 – 4.5 | 0.14 – 0.18 |
| Washington, Oregon | 3.0 – 4.0 | 0.10 – 0.12 |
| Alaska | 2.0 – 3.5 | 0.22 – 0.32 |
CO₂ Environmental Impact
Your solar system offsets approximately of CO₂ per year — equivalent to:
- Taking cars off the road for a year
- Planting trees
- Avoiding lbs of CO₂ emissions
Based on US EPA average grid emission factor of 0.428 kg CO₂/kWh.
4 Ways to Maximize Your Solar ROI
📋 Get at least 3 quotes
Solar installer prices vary 20–40% for identical systems. Always get 3+ quotes. Use the EnergySage marketplace to compare certified installers in your area transparently.
🔋 Add battery storage
A home battery (e.g. Tesla Powerwall, Enphase IQ) qualifies for the same 30% tax credit and protects against outages. In states with time-of-use rates, batteries can further reduce bills.
🗺️ Check state incentives
Beyond the federal 30% ITC, many states offer additional rebates (NY, MA, TX), property tax exemptions, and sales tax exemptions. DSIRE.org lists every available incentive by state.
⚡ Negotiate net metering
Net metering lets you sell excess solar power back to the grid, often at retail rates. Ask your installer and utility about net metering policies in your state — it significantly improves ROI in high-sun areas.
Frequently Asked Questions
The average residential solar system costs $2.50–$3.50 per watt installed, before incentives. A typical 8 kW system runs $20,000–$28,000. After the 30% federal tax credit, your net cost is $14,000–$19,600. Prices have fallen 90% since 2010 and continue to decline. Always compare multiple quotes — prices vary significantly by installer and region.
If your monthly bill is below $75–$100, the ROI may be marginal. Solar shines brightest (pun intended) for households with bills over $150/month. However, high electricity rates (California, New England) can make solar worthwhile even on modest bills. Use this calculator to check your specific numbers — payback under 10 years is generally considered a solid investment.
Most modern solar panels carry a 25-year performance warranty guaranteeing at least 80–85% of original output. In practice, many panels last 30–40 years. Annual degradation averages 0.5–0.7%. Inverters typically need replacement after 10–15 years ($1,000–$3,000). Factor this into your long-run cost analysis.
The 30% ITC is a non-refundable tax credit — you can only use it against taxes you owe. However, any unused credit carries forward to future tax years until it is fully used. If you owe $4,000/year in federal taxes and your credit is $7,200, you will use $4,000 this year and $3,200 next year. Consult a tax professional for your specific situation.