Trevor has worked in home improvement and residential solar since 2016 and maintains the EcoGen Solar Cost Index.
Power averages 41.53¢ per kilowatt-hour statewide, 131.9% above the national average and the highest in the country, and a Hawaii roof yields a solid 1,621 kWh per kilowatt a year. On Oahu, with the state credit and most of your production used at home, simple payback lands between three and five years; Hawaii Island and Maui run a little longer on their lower export credits, and the answer still turns on how much power you use in daylight. The decision worth thinking about here is not whether to install panels. It is whether to install a battery with them, and the reason is a number on your export tariff.
Hawaii Pays More for Evening Power Than Most States Charge
Hawaiian Electric closed net metering in 2015 and closed its Customer Grid Supply and Smart Export programs on March 29, 2024. New interconnections since April 1, 2024 go onto Smart DER Export, which pays a time-of-day rate under Docket 2019-0323.
Hawaii is one answer of fifty; the nationwide worth-it breakdown holds the rest.
Island | Daytime export | Evening peak, 5pm to 9pm | Overnight export |
|---|---|---|---|
Oahu | 13.5¢ | 32.9¢ | 18.9¢ |
Hawaii Island | 10.6¢ | 23.1¢ | 14.8¢ |
Maui | 6.6¢ | 18.2¢ | 13.1¢ |
Lanai | 26.7¢ | 40.8¢ | 25.9¢ |
Molokai | 17.9¢ | 27.2¢ | 17.4¢ |
Look at the Oahu row. The utility will pay you 32.9¢ for a kilowatt-hour delivered between 5pm and 9pm, which is more than households pay for electricity in every state except Hawaii itself. It will pay 13.5¢ for the same kilowatt-hour delivered at noon.
Solar panels, left to themselves, deliver at noon.
Enter your ZIP code and we will confirm which island tariff and utility apply to your address.
Confirm which island tariff applies to you
Where Each Kilowatt-Hour Can Go
On Oahu, the same unit of generation is worth four different amounts depending on what happens to it.
| What happens to the kilowatt-hour | What it is worth on Oahu |
|---|---|
| Your house uses it as it is produced | Your island’s retail rate, modeled at the 41.53¢ statewide average |
| Stored, then exported in the evening peak | 32.9¢ |
| Stored, then exported overnight | 18.9¢ |
| Exported at midday as produced | 13.5¢ |
The distance between the top and bottom rows is about 28¢ on the statewide-average basis; your island’s retail rate sets the true figure. In Hawaii a battery earns a direct arbitrage of nearly thirty cents on every unit it moves out of the midday window. Shifting two thousand kilowatt-hours a year that way is worth roughly $560 annually.
In most states a battery is a comfort purchase that lengthens payback. In Hawaii it has a defensible return of its own. A battery is a separate purchase with its own installed price, so ask any installer for that price and for the payback modeled with and without storage, on your own usage, and compare the two.
The Credit That Makes the Rest Straightforward
Hawaii’s Renewable Energy Technologies Income Tax Credit, at HRS section 235-12.5, is the most valuable state solar credit in the country: 35% of installed cost, capped at $5,000 for a residential system.
Act 24 rewrites this credit for tax years from 2027: it is disallowed in full above $175,000 of adjusted gross income filing alone or $350,000 filing jointly, it needs a certificate from the Hawaii State Energy Office, the state caps total payouts at $40,000,000 a year through 2030, and the credit ends on January 1, 2031. Executive Order 26-02 keeps the current rules for systems placed in service during 2026. If you are installing in 2027 or later and your income is over the line, run the no-credit rows.
A typical Hawaii installation is only 3.66 kW at about $11,689, among the smallest systems in the country, because households here use around 495 kWh a month. Expensive power makes people frugal with it. That system produces roughly 5,933 kWh a year.
Share your house uses directly | Annual value, Oahu export rates, self-use at the 41.53¢ statewide average | Simple payback after the state credit |
|---|---|---|
Around 85% | $2,214 | 3.4 years |
Around 60% | $1,799 | 4.2 years |
Around 40% | $1,466 | 5.2 years |
Self-used power is valued at the statewide average residential price, which is ranking context; each island files its own residential rate, so take the per-kWh figure from your own bill and rerun the rows before treating them as yours.
Even the least favorable row here is faster than a typical mainland payback. With the state credit and most production used at home, Oahu systems land between about 3 and 5 years; a household that exports most of its midday output, or one that cannot use the state credit, runs about 5 to 10 years, still ahead of nearly every mainland market. At the 60% row, Hawaii Island’s 10.6¢ daytime credit gives about $1,730 a year and 4.4 years; Maui’s 6.6¢ gives about $1,635 and 4.6 years, both on the same statewide-average self-use basis. Someone home in the daytime with electric water heating typically lands near the 60% row; a house empty from 9 to 5 with no battery lands near 40%.
The One Decision That Is Genuinely Hard
Smart DER Export offers an optional seven-year rate lock. Take it and your export rates are fixed for seven years. Decline it and they reset roughly every three years, subject to Public Utilities Commission approval.
There is no correct answer, and anyone who tells you otherwise is guessing. Hawaii has closed three successive export programs since 2015, which is an argument that locking is prudent. It has also set evening peak rates well above retail in the current program, which is an argument that the direction of travel may not be uniformly downward. What we can say is that this is a real choice with real money attached, that it is easy to sign past without noticing, and that you should make it deliberately.
When Hawaii Solar Does Not Work
The list is short, but it is not empty.
- If you rent, or the roof is not yours to alter. The most common genuine blocker in Hawaii, and no tariff fixes it.
- If you are on Kauai. The Kauai Island Utility Cooperative runs its own programs entirely, and none of the rates above describe your terms.
- If your circuit cannot accept the interconnection. Hawaii’s high adoption means some circuits are constrained, and a non-export option exists for exactly this case. Establish your circuit’s status before signing anything.
- If you owe no Hawaii income tax. The state credit is worth up to $5,000 against a liability. Without one, the payback figures above lengthen by two to three years: about 5.3, 6.5 and 8.0 years on the three rows above.
- If you install in 2027 or later and earn over $175,000 alone or $350,000 jointly. The state credit is disallowed in full above those lines from tax year 2027, so the no-credit payback of 5.3 to 8.0 years applies.
- If a quote shows a 30% federal credit. Section 25D is $0 for host-owned systems whose installation is completed after December 31, 2025 under Public Law 119-21. Hawaii’s own credit still applies.
For most Hawaii homeowners the panels justify themselves quickly and the interesting conversation is about storage, the rate lock and whether your circuit can take the connection. Our Hawaii incentives guide covers the state credit in detail, and the Hawaii installer list covers who works on each island.
Leases and power purchase agreements are legal in Hawaii; the company may qualify for the separate Section 48E business credit under current deadlines, and whether any of that value reaches your payment depends on the contract, so ask for both in writing.
Ask for the numbers modeled both with and without a battery before you decide.
Ask for the numbers with and without a battery
Hawaii Solar FAQs
Yes for most Hawaiian Electric customers, and faster than anywhere on the mainland, provided the state credit applies to you. Our modeling puts simple payback between about 3.4 and 5.2 years on Oahu for a typical 3.66 kW system costing around $11,689, after Hawaii’s 35% state tax credit. The statewide average price is 41.53¢ per kilowatt-hour here, more than double the national average. A household that exports most of its midday output, or one that cannot use the state credit, runs about 5 to 10 years. The harder question is whether to add storage.
It has a stronger case here than anywhere else. On Oahu a kilowatt-hour exported at midday earns 13.5¢, while the same unit used by your house avoids your island’s retail rate, around the 41.53¢ statewide average and one exported during the 5pm to 9pm peak earns 32.9¢. That is a gap of up to 28.03¢ per unit shifted, so moving two thousand kilowatt-hours a year out of the midday window is worth roughly $560. Ask for the payback modeled with and without storage on your own usage.
The Renewable Energy Technologies Income Tax Credit under HRS section 235-12.5, worth 35% of installed cost and capped at $5,000 for a residential system. It is the most valuable state solar credit in the country. On a typical $11,689 Hawaii installation the 35% works out to $4,091, which sits under the cap. It offsets Hawaii income tax, so a household with no Hawaii tax liability cannot use it and should recalculate accordingly.
No. Hawaiian Electric closed net metering in 2015, and closed the Customer Grid Supply and Smart Export programs on March 29, 2024. New interconnections since April 1, 2024 go onto Smart DER Export, which pays time-of-day export rates that vary by island. Kauai is served by the Kauai Island Utility Cooperative, which runs its own separate programs, so none of the Hawaiian Electric rates apply there.
It is a genuine choice with no clearly correct answer. Taking it fixes your export rates for seven years; declining it means they reset roughly every three years subject to Public Utilities Commission approval. Hawaii has closed three successive export programs since 2015, which argues for locking. The current program also sets evening peak rates well above retail, which argues the direction is not uniformly downward. Make the decision deliberately.
Methodology: figures use the EcoGen Solar Cost Index for Hawaii, a 3.66 kW system costing $11,689 as of March 1, 2026 and producing 5,933 kWh a year at 1,621 kWh per kilowatt, self-used power valued at the 41.53¢ statewide average (labeled context; your island’s filed residential rate governs), exports at the Oahu Smart DER Export daytime rate of 13.5¢, and the 35% state credit of $4,091, which sits under the $5,000 cap. No federal residential credit is included. Payback figures are simple payback at year-one values, before financing, rate escalation and degradation; the 25-year view in the Hawaii cost guide caps escalation at 4% against the state’s 5.98% five-year average.
References & Research Sources
EcoGen America reviewed the Hawaiian Electric Smart DER Export program rate sheet issued under Public Utilities Commission Docket 2019-0323, for the time-of-day export credits by island issued February 1, 2025, the program’s start on April 1, 2024, the closure of Customer Grid Supply, Customer Grid Supply Plus and Smart Export on March 29, 2024, the closure of net metering in 2015, the optional seven-year rate lock and the roughly three-year reset that applies otherwise, the advanced meter requirement and the availability of a non-export option; Hawaii Revised Statutes section 235-12.5 for the Renewable Energy Technologies Income Tax Credit at 35% of installed cost capped at $5,000 for a residential system; EIA Electric Power Monthly for the 41.53¢ residential price and the five-year growth rate of roughly 5.98% a year; and IRS guidance on the Public Law 119-21 termination of Section 25D for host-owned systems whose installation is completed after December 31, 2025; Act 24 (Senate Bill 3125) for the $175,000 and $350,000 adjusted gross income limits, the Hawaii State Energy Office certificate requirement, the $40,000,000 annual statewide cap through 2030 and the January 1, 2031 end date, all applying to tax years beginning after December 31, 2026; and Executive Order 26-02 of June 12, 2026 for the preservation of the current rules for systems placed in service during 2026. Output of 1,621 kWh per kilowatt per year, 5.81 peak sun hours, the 3.66 kW system size, the $11,689 installed cost and the 495 kWh monthly usage are EcoGen America figures for Hawaii dated March 1, 2026. Kauai is served by the Kauai Island Utility Cooperative and is not covered by the Hawaiian Electric rates above. Utility shares of residential customers are from EIA-861 2024. Sources accessed between June 10 and August 18, 2026.
