Solar Panel Savings Calculator

1. Enter your monthly electricity bill and your electricity rate in $/kWh.
2. The system size is automatically calculated to match your usage. You can override it manually if you have a specific quote.
3. Adjust the cost per watt, tax credit percentage, and any state incentives.
4. Set the annual electricity rate increase, panel degradation rate, and peak sun hours for your region.
5. If financing, enter the loan interest rate and term. Use 0% for a cash purchase.
6. View the key metrics: net cost, break-even year, lifetime savings, ROI, and CO2 offset.
7. Expand the comparison and year-by-year sections for detailed analysis.

How Solar Savings Work

Solar panels generate electricity from sunlight, reducing or eliminating your monthly utility bill. The savings come from two sources: the electricity you produce and consume directly (avoiding the purchase from your utility), and any excess energy you send back to the grid through net metering. Over time, as electricity rates rise, the value of the energy your panels produce increases while your system cost remains fixed. This calculator models both panel degradation and rate increases to project realistic long-term savings.

Federal Solar Tax Credit (ITC)

The Investment Tax Credit is the single largest incentive for residential solar. Under the Inflation Reduction Act of 2022, the ITC is set at 30% through 2032 for systems installed on residential properties. This credit is applied directly against your federal income tax liability, making it far more valuable than a deduction. For a $20,000 solar system, the ITC would be worth $6,000 in tax savings. Many states and utilities offer additional rebates, performance-based incentives, and property tax exemptions on top of the federal credit.

Factors Affecting Solar ROI

• Electricity rate: Higher utility rates mean faster payback and greater lifetime savings.
• Sun exposure: The Southwest US averages 6 to 7 peak sun hours per day, while the Northeast averages 3 to 5. More sun means more production.
• System cost: Prices vary by installer, equipment, and roof complexity. Get multiple quotes to find the best value.
• Net metering policy: States with full retail net metering allow you to earn the full retail rate for excess energy sent to the grid.
• Rate increases: US electricity rates have historically increased 2% to 4% annually. Higher future rates mean greater future savings.
• Financing terms: Paying cash eliminates interest costs and maximizes ROI. Low-interest solar loans are also widely available.
• Roof orientation: South-facing roofs in the Northern Hemisphere produce the most energy. East/west facing roofs produce 10% to 20% less.

Environmental Impact

The average US household produces about 14,000 to 16,000 lbs of CO2 per year from electricity use. A properly sized solar panel system can offset the majority or all of this carbon footprint. Over a 25-year system life, this adds up to roughly 150 to 200 tons of CO2 avoided. This calculator estimates CO2 offset using the EPA average of 0.855 lbs of CO2 per kWh of electricity generated. The actual offset varies by region based on the local grid's energy mix.

Compare with our Electricity Cost Calculator to understand your current energy spending. Analyze investment returns with the ROI Calculator, or plan your long-term savings with the Savings Calculator.