Solar Panel Payback Period

System cost / annual savings = years to break even on a residential solar install.

Inputs

Result

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General calculation reads

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How to use this calculator

  • Enter post-incentive system cost.
  • Enter monthly electric bill.
  • Pick offset % (typical 80-100% of usage).
  • Default 3% inflation reasonable for US.

About this calculator

Residential solar pays back in 7-12 years in most US markets at typical electricity rates and after federal/state incentives. Including rate inflation (electricity prices typically rise 3% / year), payback is faster than a flat-rate calculation suggests. Panels last 25-30 years, so solar is generally a 15-20-year cash-positive investment.

Frequently asked

What's "after incentives"?+
30% federal ITC + state-specific (varies). $30k gross → $21k after federal alone. Use the post-incentive figure.
Why does inflation matter?+
Because as electric rates rise, your savings grow. A 3% inflation makes payback 1-2 years faster than flat-rate analysis.
Solar in cloudy areas?+
Less production, slower payback. NREL's PVWatts tool gives location-specific production estimates.
What about battery storage?+
Adds $10-15k typically. Doesn't directly improve payback but gives blackout protection and time-of-use arbitrage.
Net metering?+
Allows excess production to credit your bill. Critical for 90%+ offset. Some states cap or are phasing out net metering — check your utility.

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