How We Make Money

Every calculator and guide on this site is free, and no tool is behind a signup. Here is exactly how the site earns revenue, and the rules that keep that revenue from touching our editorial calls.

Affiliate commissions

Some product links on this site are affiliate links, marked as rel="sponsored" in the page source and routed through our own /go/ redirects. If you click one and buy something, the merchant may pay us a commission. The price you pay is the same either way.

What money cannot buy here

  • No paid placements. Merchants and manufacturers cannot pay to appear in a review, a comparison table, or a quick-picks list. Products appear because our editors chose to cover them.
  • No sponsored scores. Our reviews do not assign scores at all. Every capacity, wattage, and warranty figure comes from manufacturer documentation cross-checked against named third parties, and gaps are printed as gaps.
  • No link in exchange for coverage. A product can be reviewed with no affiliate link, and an affiliate link can be removed without changing a word of prose.

Installer leads, when they come

Later, this site may introduce a paid introduction service for solar installers. If and when that launches, any installer shown in connection with it will be labeled as a paid placement on the page where it appears, and it will never influence calculator outputs or review content.

Why we publish this page

Disclosure is a legal requirement (FTC endorsement guides in the US, Competition Bureau guidance in Canada) and a trust practice. If you ever see a commerce link on this site that is not covered by the rules above, that is a bug, and we want to hear about it on our contact page.

Written & reviewed by

EnergyTools Research Team — Solar Energy Research Group

The EnergyTools Research Team compiles and verifies residential solar data from NREL, EPA, and state utility commissions. Methodology is reviewed quarterly.

  • Source data: NREL PVWatts V8 + Utility Rates V3 APIs
  • Source data: EPA FuelEconomy.gov vehicle efficiency data
  • Methodology reviewed quarterly

Methodology & data sources:NREL PVWatts, EPA FuelEconomy.gov, state utility commissions— updated 2026.