Hawaii County, HI Solar Energy: Panel Permits (2026)

Section 5-3-1(b)(4) of the Hawai'i County Code puts solar photovoltaic systems on the same footing as any other regulated construction: a permit is required for a complete new installation, for replacing an existing system with all-new components, and for relocating panels from a roof mount to a ground mount or the reverse. The same subsection separately requires a permit for solar water-heating systems, so a homeowner combining PV with solar hot water needs to account for both triggers. Section 5-4-3(f) adds a professional-design layer once the system crosses certain thresholds.

Residential installations with a cumulative capacity greater than 10 kilowatts, and every non-residential installation regardless of size, need electrical design drawings prepared, designed, and stamped by a Hawai'i-licensed professional electrical engineer. Building-work plans for the racking and structural attachment need a similar stamp from a licensed architect or professional structural engineer whenever the installation is non-residential, or whenever a residential system skips a preapproved design or departs from approved standards such as span tables, older-home framing, or site-built trusses. Smaller, standard residential systems using a preapproved design avoid the stamped-drawing requirement but still need the underlying permit itself; nothing in Section 5-3-1 exempts small systems from that baseline permit.

The Director of Public Works, as the code's authority having jurisdiction under Section 5-2-1, reviews and issues every solar permit, and the same valuation-based fee schedule and six-year expiration that governs ordinary construction work under Sections 5-7-3 and 5-5-4 applies to photovoltaic permits as well.