Where our information comes from
Our guides are compiled from primary sources: state program administrators (Illinois Shines, the CPUC, Hawaii's Department of Taxation), utility tariff pages and program documentation (Hawaiian Electric, PG&E, SCE, SDG&E, ComEd, Ameren, and municipal utilities), the IRS, and federal energy statistics from the U.S. Energy Information Administration. Every state guide ends with a source list including the date we last checked each source.
How estimates are built
City and state savings figures are calculated from public residential electricity rates and typical household usage, combined with regional sun-hour data. They are directional estimates meant to help you compare markets — not quotes. Your actual costs and savings depend on system size, roof characteristics, equipment, installation requirements, financing, your utility's current programs, and installer pricing. Every estimate on this site is labeled as such.
Review cadence
Solar policy changes on program timelines, not news cycles. Each guide carries a "last reviewed" date, and we prioritize re-review when programs are known to change — block pricing steps in Illinois, export-rate updates in California, and battery program revisions in Hawaii. If a program's status is uncertain, we say so and link to the official source rather than guessing.
What we will not publish
- Fabricated testimonials, reviews, star ratings, or "as seen in" logos.
- Invented install counts, customer counts, or awards.
- Specific installer pricing presented as fact, or "guaranteed savings" claims.
- Countdown-timer urgency around incentives that have no actual deadline.
How referrals relate to content
We may be compensated when you request quotes through our forms. Editorial content is produced independently of that compensation: program descriptions, cost ranges, and cautions (including warnings about sales tactics) are written from the sources, not from partner relationships. Being mentioned on this website does not automatically mean a company or program is the best option for every homeowner. Full details are in our Affiliate & Compensation Disclosure.
Corrections
If you find an error or an out-of-date program detail, contact us. We correct verified errors and update the page's review date.