Ontario, CA Solar Energy: Panel Permits (2026)

01 applies Chapter 8 to the permitting of all small residential rooftop solar energy systems in Ontario, but exempts systems legally established before the chapter took effect unless physical modifications materially change their size, type, or components; routine operation, maintenance, and like-kind replacements never require a new permit. 02 defines the systems eligible for this streamlined path: no larger than ten kilowatts AC nameplate rating or thirty kilowatts thermal, conforming to state fire, structural, and electrical codes plus applicable Public Utilities Commission safety rules, installed on a single or duplex family dwelling, and with a panel or module array that does not exceed the City's maximum legal building height.

Water-heating solar systems must be certified by an accredited listing agency under the California Plumbing and Mechanical Codes, while electricity-producing systems must meet California Electrical Code and IEEE safety and performance standards, verified by testing laboratories such as Underwriters Laboratories. 03 requires the Building Department to publish a checklist and standard plan for expedited-eligible systems on the City's website, accept electronic submittal of applications by email or fax, and accept an applicant's electronic signature in place of a wet signature. The checklist and process must substantially conform to the California Solar Permitting Guidebook published by the Governor's Office of Planning and Research, giving Ontario applicants a state-standardized path rather than a locally invented one.