Oahu · NEC 2020 · HECO Customer Self-Supply · Highest US Electricity Rates
Honolulu Solar
Permit Design.
HECO Customer Self-Supply.
No Traditional Net Metering · Battery Essential · $0.40+ Rates.
Honolulu solar permit drawings for City and County of Honolulu. HECO (Hawaiian Electric) ended traditional net metering in 2015 — new customers use Customer Self-Supply (CSS) with no export credit, or Grid Supply at low export rates. Hawaii electricity costs $0.40+ per kWh — highest in the US. Battery is essential under CSS. Hawaii 35% state tax credit. NEC 2020. Free for first-time clients.
HECO CSS Customer Self-Supply · Battery essential
·$0.40+ Per kWh · Highest US rates
·HI 35% State income tax credit · Up to $5,000
·Free AHJ revisions
$0.40+/kWhHighest US electricity rates · Best solar economics nationally
HECO CSSNo traditional net metering since 2015
HI 35%State income tax credit up to $5,000
24–48 hrStandard plan set delivery
2026 CodesElectrical: NEC 2020 (Hawaii)Structural: IBC 2018 (Hawaii)Utility: HECO (Hawaiian Electric) · Customer Self-Supply (CSS) or Grid SupplyAHJ: City and County of Honolulu Dept of Planning and Permitting (DPP)Last verified July 2026
HECO Has Not Offered Traditional Net Metering Since 2015 — Battery Changes Everything
HECO Customer Self-Supply: All Solar Generation Stays On-Site. No Export Credit. Battery Captures Midday Surplus for Evening Use. Hawaii Rates of $0.40+ Per kWh Make This the Strongest Solar ROI in the US.
HECO (Hawaiian Electric) ended traditional net metering for new residential customers in 2015. New customers choose between Customer Self-Supply (CSS) — all solar generation consumed on-site, no grid export — or Grid Supply, where excess generation is exported at a grid-avoided-cost rate far below retail. Hawaii’s electricity costs $0.40 or more per kWh, the highest in the United States by a significant margin. Every kilowatt-hour of solar self-consumed under CSS avoids purchasing electricity at that rate. Battery storage is essential under CSS to capture midday surplus and dispatch it during evening peak — maximizing the value of every solar kilowatt-hour produced.
HECO Customer Self-Supply — No Export, Battery Essential
⚠️HECO CSS: all solar generation consumed on-site — no export to the grid, no export credit
⚠️Without battery, midday surplus is wasted — CSS produces zero export credit for unused generation
✅Battery captures midday surplus and dispatches for evening use at full $0.40+ avoided cost value
⚠️Grid Supply alternative: exports credited at grid-avoided-cost rate (~15¢) vs $0.40+ retail
✅CSS with battery eliminates most or all daytime grid purchases — strongest residential solar ROI in US
$0.40+ Rates · HI 35% Tax Credit · NEC 2020 · DPP AHJ
✅Hawaii electricity rates $0.40+ per kWh — highest in the US — every avoided kWh saves maximum value
✅Hawaii 35% state income tax credit for solar systems — capped at $5,000 per system
⚠️Hawaii 35% credit is non-refundable — requires HI state income tax liability to utilize
✅NEC 2020 under Hawaii state adoption
✅City and County of Honolulu DPP is the single AHJ for all Oahu solar permits
⚠️ Battery is not optional under HECO Customer Self-Supply — it is the mechanism that makes CSS financially complete. Under CSS without battery, midday solar generation that exceeds the home's immediate load is sent to the grid at zero credit. Battery is the tool that captures this surplus and converts it to avoided-cost savings at $0.40+ per kWh.
Why Honolulu Installers Outsource
CSS Without Battery Wastes Midday Generation. HI Tax Credit Misrepresented. HECO Interconnection Not Formatted.
Proposing CSS Solar Without Battery Wastes 20–40% of System Value
Under HECO Customer Self-Supply, any solar generation that exceeds the home's immediate load at any moment is exported to the grid at zero credit. A 6 kW system producing 3 kW during low-load midday hours loses half its production value without battery to capture the surplus. A CSS proposal without battery leaves 20 to 40% of system value uncaptured. Battery is the financial centerpiece of Honolulu solar, not an upgrade.
Hawaii 35% Tax Credit Is Non-Refundable — Not All Customers Can Fully Use It
Hawaii's 35% state income tax credit (capped at $5,000) is non-refundable. Customers with low Hawaii state income tax liability may not be able to claim the full credit in one year — though it can be carried forward. Presenting the $5,000 credit as a guaranteed immediate benefit to customers with limited HI state tax liability creates inaccurate financial projections and damages trust when the actual credit is less than expected.
HECO Interconnection Process Is Complex — Feeder Capacity Limits Apply
HECO's interconnection process includes feeder capacity limits — some Oahu circuits are at or near their solar hosting capacity, requiring engineering review or system size reduction. HECO interconnection can take significantly longer than mainland utility interconnections in some neighborhoods due to feeder saturation. Understanding current feeder status for the address is an important pre-project check.
Honolulu Solar Permit Services
HECO (Hawaiian Electric) Interconnection. NEC 2020. All Honolulu AHJs.
Honolulu Residential Solar Permit Design
NEC 2020, IBC 2018 (HI). HECO interconnection package formatted for CSS or Grid Supply per customer choice. City and County of Honolulu DPP AHJ format. Battery (NEC 2020 Article 706) — strongly recommended under CSS. Hawaii 35% tax credit documentation note.
Residential Solar Permit Design Services →Honolulu Commercial Solar Permit Design
Commercial rooftop drawings for Oahu. NEC 2020, IBC 2018. HECO commercial interconnection. Honolulu's hotel, resort, retail, and military installation sector creates large commercial rooftop solar demand. PE stamp. Hawaii wind and seismic ASCE 7 calcs for island conditions.
Commercial Solar Permit Design Services →Honolulu Battery Permit Plans
Solar-paired battery permit drawings. NEC 2020 Article 706, HECO storage interconnection. Battery is functionally required under HECO CSS to capture midday surplus. At $0.40+ per kWh, every stored kilowatt-hour is worth more in Hawaii than anywhere else in the US. Hurricane resilience is an additional meaningful benefit.
Battery Storage Permit Design Services →Honolulu EV Charger Permit Design
EV charger permit drawings for Oahu. NEC 2020 Article 625. Hawaii has a high EV adoption rate driven by $0.40+ electricity costs paired with solar, making the solar + battery + EV combination one of the most financially compelling in the US. Resort, military, and government fleet EV also strong.
EV Charger Permit Design Services →Honolulu Solar Market — 2026
Four Things That Define Solar in Honolulu.
$0.40+/kWh
Hawaii Has the Highest Electricity Rates in the US — Best National Solar Economics
Hawaii electricity rates exceed $0.40 per kWh — more than double the US average and more than triple the rates in Pacific Northwest hydro markets. Every kilowatt-hour of solar self-consumed under HECO CSS avoids purchasing electricity at this rate. A 6 kW system avoiding 20 kWh of grid purchases daily saves $8 per day at $0.40 per kWh — over $2,900 per year. Hawaii's extreme electricity rates create the strongest residential solar ROI in the United States.
HECO CSS
Customer Self-Supply — No Traditional Net Metering Since 2015
HECO's traditional net metering closed to new customers in November 2015. New residential solar customers choose Customer Self-Supply (CSS) or Grid Supply. CSS keeps all solar generation on-site with no export — battery is required to capture midday surplus. Grid Supply exports at a grid-avoided-cost rate far below retail. CSS with battery has become the dominant residential solar configuration in Honolulu since 2016.
HI 35%
Hawaii 35% State Income Tax Credit — Up to $5,000 Per System
Hawaii offers a 35% state income tax credit for solar energy systems, capped at $5,000 per system. The credit is non-refundable but can be carried forward. Hawaii also has a general excise tax (GET) exemption on solar systems. These incentives partially offset the higher upfront costs of solar plus battery installations in Hawaii.
DPP AHJ
City and County of Honolulu DPP — Single AHJ for All Oahu Solar Permits
Unlike mainland metros with many separate building departments, City and County of Honolulu has a single permitting authority for all Oahu addresses: the Department of Planning and Permitting (DPP). This unified AHJ structure simplifies the permitting process compared to markets like Miami (36 departments) or Atlanta (many county departments). One permit office, one process, for all Oahu solar installations.
AHJ Solar Permit Design Honolulu
Honolulu and All Surrounding Jurisdictions — HECO (Hawaiian Electric) Interconnection Formatted.
City and County of Honolulu DPP is the single AHJ for all Oahu solar permits. HECO interconnection formatted for CSS or Grid Supply.
| Jurisdiction | Utility | Permit Type | Key Notes | Review Time |
|---|---|---|---|---|
| All Oahu Addresses | HECO | Bldg + Elec | City and County of Honolulu Dept of Planning and Permitting (DPP) · One AHJ for all Oahu | 3–6 weeks |
| Honolulu / Honolulu District | HECO | Bldg + Elec | DPP · Central Oahu · Urban core · High density residential | 3–5 weeks |
| Kailua / Kaneohe (Windward) | HECO | Bldg + Elec | DPP · Windward Oahu · Suburban residential · High solar demand | 3–5 weeks |
| Pearl City / Aiea / Ewa Beach | HECO | Bldg + Elec | DPP · Central and West Oahu · Growing residential market | 3–5 weeks |
| Kapolei (West Oahu) | HECO | Bldg + Elec | DPP · West Oahu growth corridor · New construction solar | 3–5 weeks |
| North Shore / Haleiwa | HECO | Bldg + Elec | DPP · Rural Oahu · Lower density · Occasional feeder capacity review | 4–6 weeks |
| Hawaii Kai / East Honolulu | HECO | Bldg + Elec | DPP · East Oahu · Affluent residential · High solar adoption | 3–5 weeks |
References: HECO Customer Self-Supply · Honolulu DPP
What You Get
Solar Permit Package Honolulu — Honolulu Solar Permit Plan Sets. HECO (Hawaiian Electric) Ready.
01
Cover Sheet — Honolulu PV Permit Plans
NEC 2020 · IBC 2018 (HI) · Honolulu AHJ · HECO (Hawaiian Electric) utility
02
Site Plan
Meter and HECO (Hawaiian Electric) interconnection access · ASCE 7 local wind values · Applicable wind zone
03
Roof Layout
Honolulu rooftop conditions · Array diagram · Pitch, azimuth, setbacks · IFC fire access paths
04
Single-Line Diagram
NEC 2020 §690.12 rapid shutdown · Battery (Article 706) where included · HECO (Hawaiian Electric) bidirectional meter
05
Structural Calculations
IBC 2018 (HI) · ASCE 7 local wind loads · Gravity and lateral loads · PE stamp for commercial
06
Rapid Shutdown + Labels
NEC 2020 §690.12 · Battery shutdown interface (Article 706)
07
Equipment Datasheets + HECO (Hawaiian Electric) Interconnection Package
UL-listed module, inverter, racking, and battery datasheets · HECO (Hawaiian Electric) interconnection application · State solar incentive notes
Honolulu Plan Set — 24 Hours.
HECO (Hawaiian Electric) Interconnection · NEC 2020 · All Honolulu AHJs
How It Works
Three Steps. 24 Hours. Honolulu AHJ Ready.
📋
Submit the Project
Share address, specs, and design. We confirm the AHJ, HECO (Hawaiian Electric) interconnection, and NEC 2020 format.
5 minutes⚡
We Build the Plan Set
NEC 2020, IBC 2018 (HI). Honolulu AHJ formatted. HECO (Hawaiian Electric) interconnection package. Battery where included.
24–48 hours✅
Submit Permit + Interconnection
Submit Honolulu DPP permit and HECO interconnection for CSS or Grid Supply simultaneously. HECO interconnection: 4–12 weeks (feeder-dependent). Free revisions for any AHJ correction on our design.
Free revisions🛡️
The Permit Design Commitment
Solar permit services in Honolulu — what every installer and EPC gets.
✓AHJ confirmed per address before we build
✓HECO (Hawaiian Electric) interconnection package included
✓24–48 hour delivery on standard residential projects
✓NEC 2020 formatted for HI — not California NEC 2026
✓Free revisions for any AHJ correction on our design
Start Free Trial →
First plan set free.
Licensed installers & EPCs only.
Licensed installers & EPCs only.
FAQ
Questions Honolulu Installers Ask Us
HECO (Hawaiian Electric) has not offered traditional net metering for new customers since 2015. New residential solar customers choose between Customer Self-Supply (CSS) — where all solar generation is used on-site with no export to the grid — or Grid Supply, where excess solar is exported at a very low grid-avoided-cost rate (roughly 15 cents vs $0.40+ retail). CSS with battery is the dominant residential choice because it eliminates grid imports during daytime hours.
Under Customer Self-Supply, solar energy that exceeds your home's immediate load at any moment is essentially wasted — it cannot be exported for credit. Battery storage captures midday surplus and dispatches it during evening peak, keeping the full system value. Without battery under CSS, a typical residential solar system loses 20 to 40% of its potential value to wasted midday generation.
Hawaii offers a 35% state income tax credit for solar energy systems, capped at $5,000 per system. The credit is non-refundable — requires Hawaii state income tax liability to utilize. The credit can be carried forward if not fully used in the installation year.
NEC 2020 under Hawaii state adoption.
Hawaii has no statewide PE stamp requirement for standard residential rooftop solar under standard size thresholds. City and County of Honolulu DPP does not typically require a PE stamp for standard residential rooftop installations. Commercial and larger systems require PE-stamped structural drawings.
City and County of Honolulu Department of Planning and Permitting (DPP) is the AHJ for all Oahu residential and commercial solar permits.
Most Honolulu residential plan sets ship in 24 to 48 hours. Battery same day. Commercial: 3 to 5 business days. Rush available.
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Reviewed by the Permit Design Engineering Team — Licensed PE
HECO CSS (Customer Self-Supply, no traditional net metering since Nov 2015) confirmed from HECO program documentation. Hawaii electricity rates ($0.40+/kWh) confirmed from HECO rate schedules. Hawaii 35% state income tax credit (capped at $5,000/system, non-refundable) confirmed via Hawaii DBEDT. NEC 2020 Hawaii adoption confirmed. City and County of Honolulu DPP as single Oahu AHJ confirmed. Last reviewed July 2026.