The solar panels vs utility cost comparison calculates your 25-year cumulative savings, break-even year, and return on investment. Includes the 30% federal Investment Tax Credit (ITC). Results are estimates — actual savings depend on roof orientation, shading, and local net metering policy.
Solar Calculator Inputs
US average ~$3.00-4.00/watt installed (2026)
Historical avg ~3%/yr
Year-by-Year Savings
| Year | Annual Savings | Cumulative Savings | Net Benefit |
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How to Calculate Solar Panel Return on Investment
Solar ROI depends on three main factors: your electricity bill (how much solar offsets), the system cost after incentives, and your local electricity rate trajectory. States with high rates and abundant sunlight have the shortest payback periods.
Understanding system sizing
System size (kW) is calculated from your monthly usage: (monthly kWh) / (average peak sun hours × 30 days). A $150/month bill at $0.16/kWh means ~938 kWh/month. At 4.5 peak sun hours, you'd need a roughly 7 kW system.
The 30% federal ITC explained
The Investment Tax Credit is a dollar-for-dollar reduction of your federal income tax liability. A $24,500 system ($3.50 × 7 kW) gets a $7,350 credit — reducing effective cost to $17,150. You must have sufficient tax liability to use the full credit. Any unused credit carries forward to future tax years.
Net metering matters
Net metering credits you at retail rates for excess electricity exported to the grid. Without net metering (or with reduced credit rates), solar economics change significantly. Check your utility's current net metering policy — some states have reduced these credits recently. One-for-one net metering is the most favorable scenario.
Frequently Asked Questions
Is this solar vs utility calculator free?
Yes, completely free with no signup required. Actual savings depend on your roof orientation, shading, local net metering policy, and utility rate changes.
What is the federal solar tax credit in 2026?
The Investment Tax Credit (ITC) allows homeowners to deduct 30% of the total solar system cost from their federal income taxes. For a $20,000 system, the credit is $6,000 — reducing your effective cost to $14,000. The credit applies to both purchased systems and financed systems (not leased). The 30% rate runs through 2032.
How long until solar panels pay for themselves?
The typical solar payback period in the US is 6-12 years. States with high electricity rates (California, Hawaii, Connecticut) often see payback in 5-8 years. States with cheap electricity (Louisiana, Idaho) may take 12-15 years. With the 30% tax credit, payback periods shorten by 2-4 years compared to the pre-credit full price.
What happens after the payback period?
After the break-even point, your solar electricity is essentially free. A system with a 7-year payback on a 25-year panel warranty provides 18 years of free electricity — potentially $15,000-30,000 in savings depending on your usage and rate increases. Panels typically produce at 80-85% capacity at year 25.
Does solar increase home value?
Yes — the National Renewable Energy Laboratory (NREL) found that solar installations increase home sale prices by an average of $4/watt or about $15,000-20,000 for a typical system. Zillow research shows solar homes sell for 4.1% more. This value isn't captured in the energy savings calculation but adds to overall ROI.