Disclaimer
Every figure on this site is a planning estimate. This page explains what that means, in detail.
Planning estimate only - not tax, legal or financial advice. Confirm installed cost and current incentives with a licensed installer and the official IRS and Energy.gov sources.
SolarPayback provides educational estimating tools and general reference information about residential solar payback. It is not professional energy, engineering, tax, legal or financial advice, and it is not a substitute for any of them. Using the calculators does not create a professional relationship of any kind.
Estimates, by construction
Payback periods, savings and generation figures are simplified models of a complex system. Real-world results depend on your roof’s azimuth and tilt, shading from trees and buildings, local weather patterns, panel and inverter degradation, installation quality, your utility’s exact rate schedule and its future changes, and incentive programs whose rules and caps are amended by legislatures and regulators. The calculators state their assumptions; if your situation differs, the output differs. Two homes on the same street can see meaningfully different returns.
Policy figures carry dates
Federal and state incentive treatment is stated as of the review date shown on each page, read from official sources including IRS publications and Energy.gov guides. Tax law, tariff rules and state programs change. A figure that was correct at review may be superseded before the next cycle, so verify anything material against the current official source before relying on it.
Not a purchase recommendation
Nothing here recommends buying or not buying a solar system. The tools exist to make you a better evaluator of quotes you already have. Before signing any contract: obtain multiple written quotes from licensed installers; confirm the export tariff in your utility’s service agreement; and for any tax position, consult a qualified tax professional who knows your filing situation.
Limitation of liability
To the fullest extent permitted by law, the site’s operators disclaim liability for decisions made or actions taken in reliance on the site’s content, including financial losses, foregone savings, tax outcomes and contract disputes. Your use of the site is at your own discretion.
Corrections
Found a figure that looks wrong or stale? The contact address in the footer reaches a human, and verified corrections are applied between review cycles with priority.