What decides the answer in Hawaii
Hawaiian Electric (Oahu, Maui, Lanai, Molokai and Hawaii Island) credits new rooftop exports under Smart Renewable Energy Export. Its published "Smart Renewable Energy (SRE) - Export rates for 2024-2026", in cents/kWh for overnight (9pm–9am), daytime (9am–5pm) and evening peak (5pm–9pm), are: Oahu 18.9, 13.5 and 32.9; Maui 13.1, 6.6 and 18.2; Lanai 25.9, 26.7 and 40.8; Molokai 17.4, 17.9 and 27.2; Hawaii Island 14.8, 10.6 and 23.1. The page says "Export credits will be trued-up on an annual basis and any remaining credits left over at the end of the year expire", with an exception for BYOD Plus export credits. Export rates "will be updated every 3 years" and "are locked in for the first 7 years of any new interconnection agreement". Customer Grid-Supply, Grid-Supply Plus and Smart Export customers transition seven years after their contract date and do not get that lock-in. Legacy NEM and NEM Plus have separate options. A neighbor's grandfathered credit is not an offer to a new applicant. The table is labelled 2024–2026, and Hawaiian Electric's page lists no export rates for later years. [1] [2]
Without a battery, a rooftop system exports mostly in daytime, which pays the lowest rate on Oahu, Maui and Hawaii Island. The benchmark row values every kWh at the 42.86-cent state average, which a new applicant's exports do not earn under this program; the battery credit under BYOD Plus, described below, is the one exception on the page. The household no-incentive row assumes a single 15-cent export price for all hours, which the model raises 3% a year together with the 40-cent import price, and 40% self-use; it gives a modelled 6.8 years. The four published-rate rows below keep the same import price and self-use but hold each island's export credit at its locked rate, with no increase during or after the seven-year lock. Their modelled paybacks are 7.0 years for Oahu with an assumed time-of-day mix, 7.3 years for Oahu with every export at the 13.5-cent daytime rate, 7.9 years for Hawaii Island at 10.6 cents and 8.6 years for Maui at 6.6 cents. Crediting every export at the daytime rate slightly overstates payback, because overnight and evening-peak exports earn more on all three islands; the two Oahu rows show the size of that effect. None of these rows subtracts credits lost at the annual true-up, which matters if export credits exceed what the bill can absorb over the year. [2] [7]
The storage row assumes 75% self-use and 10,000 dollars of added cost, with no incentive and no evening-peak exports. Hawaiian Electric's Bring Your Own Device Plus program pays an upfront incentive of 400 dollars per kW committed, and another 400 dollars per kW for qualifying low-to-moderate-income customers. The battery must be new and discharge during a two-hour window the customer chooses, every day. The page states a 5-year participation requirement in one place and a "10-year commitment" in another. It also says BYOD Plus customers "will also receive monthly export credits for the energy sent to Hawaiian Electric at the retail rate of customer’s current billing rate", with the monthly credit "calculated based on an assumed exported amount to the grid", and the export program page adds that "BYOD Plus Export credits do not expire." The storage row includes none of this: not the upfront incentive, not the monthly battery credit or its exemption from the annual expiry, and not Oahu's 32.9-cent evening-peak export rate. N-342 also says any utility rebate must be deducted from qualifying cost before the tax credit is figured. [7] [2] [3]
The N-342 instructions (revision 2025) set the single-family PV credit at the lesser of 35% of actual cost or 5,000 dollars, and define a system by output: "Single-family residential property - 5 kilowatts per system". Their example gives an 8.5 kW array "2 credits", a 5.0 kW and a 3.5 kW system, with cost "allocated accordingly". Applied to the modelled 7 kW, 22,400-dollar array (3,200 dollars per kW), that means a 5 kW system costing 16,000 dollars (35% is 5,600, capped at 5,000) and a 2 kW system costing 6,400 dollars (35% is 2,240). The total is 7,240 dollars. Received at the end of year two, it gives a modelled payback of 4.7 years, against 5.4 years for the single 5,000-dollar credit shown below and 6.8 years with no credit. For solar, you may elect to "reduce the eligible credit amount by 30%" and have any excess over tax due refunded. If the 30% comes off each capped credit, that is 5,068 dollars (modelled 5.3 years); if it comes off 35% of cost before the cap, 5,488 dollars (5.2 years). The instructions do not say which. Without that election, unused credit carries forward to later years. [3]
DOTAX Tax Information Release 2026-02 (July 31, 2026) says Act 24 imposed an annual 40 million dollar aggregate credit cap retroactive to the beginning of 2026, so "credits claimed in 2027 for renewable energy technologies systems installed and placed in service in 2026, will be subject to the annual credit cap." Following Executive Order 26-02 (June 8, 2026), the cap does not apply to systems installed and placed in service before May 21, 2026. It also does not apply to systems placed in service by the end of 2026 whose owner can show a payment made or cost incurred for the system before May 21, 2026. Eligibility for that exemption "will be determined through a certification process, information for which will be provided later." A contract signed now with no earlier payment falls under the cap, and the TIR does not say how the cap is shared among claimants. For systems placed in service in 2027 or later, HSEO says Act 24 brings "new eligibility requirements, certification provisions, aggregate credit limits, and a future sunset of the credit" for taxable years after December 31, 2026. This page does not model those later rules, so the credit rows apply only to a 2026 system that qualifies. This note relies on HSEO's summary and TIR 2026-02, not on the text of Act 24. [6] [5] [4]
The three credit rows put the same 5,000 dollars at the end of year two, year three or year six. The year-two and year-three rows both print 5.4 years, because the model does not discount future dollars and both receipts arrive before break-even. The year-six receipt comes later than that 5.4-year crossing, so that row prints 6.0 years. Each row's own text lists its cumulative cash year by year, which is where the timing difference shows. [3]
Sunlight: the state input is PVWatts v8 at Hawaii's 2020 Census center of population (21.112376, −157.485304). That point is offshore, between Oahu and Molokai, and its weather-data cell is 2,463 m away. With the same settings (listed on the methodology page and in the PVWatts source below), PVWatts v8 returns 5.82 kWh/m²/day at Honolulu (21.3069, −157.8583) and 4.58 at Hilo (19.7074, −155.0885), against 6.16 used here. With the no-incentive household inputs, those give a modelled 7.2 and 8.9 years instead of 6.8. Kauai is served by Kauai Island Utility Cooperative, not Hawaiian Electric, and is not covered here. KIUC describes Schedule Q as the program by which it "pays you for the excess power you generate", at a rate that "changes monthly". [9] [8]
How Hawaii pays for an exported kilowatt-hour
Export value differs from the full retail bill. The hypothetical household, storage and tax-credit rows use an assumed flat 15-cent export price; the four island rows use the published rates instead. Hawaiian Electric's published 2024–2026 daytime export rates are 13.5 cents on Oahu, 6.6 on Maui and 10.6 on Hawaii Island (higher on Lanai and Molokai), and leftover credits expire at the annual true-up. A non-export program would need curtailment or dispatch modelling, not just an export price of zero with all production still usable. The scenarios keep an export-capable system.
No federal residential credit is applied by default in any calculator or state benchmark on this site (Section 25D expired at the end of 2025), and the mechanics of export regimes are covered in the net metering guide.
Sources for the Hawaii section above
- Hawaiian Electric renewable program comparison — Named transition cohorts and distinction from legacy NEM.
Document: Previous Programs / program selector. Effective/source period: First legacy transitions October 1, 2024; seven-year enrollment condition.
Applies to: Hawaiian Electric program customers, not all Hawaii utilities. Relevant passage: “after 7 years in their current program”.
- Hawaiian Electric Smart Renewable Energy Export — Published island and time-of-day export rates, annual credit expiry and 7-year lock-in.
Document: Billing and Export Rates table; 7 Year Lock In. Effective/source period: Export rates for 2024-2026; updated every 3 years; locked for 7 years on new agreements.
Applies to: Hawaiian Electric customers on Oahu, Maui, Lanai, Molokai and Hawaii Island; not Kauai. Relevant passage: “any remaining credits left over at the end of the year expire”.
- Hawaii DOTAX N-342 instructions — Per-system output rule and cost allocation, credit rate and cap, refundable election and utility-rebate deduction.
Document: Instructions for N-342, revision 2025, pp. 1–3. Effective/source period: 2025 form instructions; not a standalone 2026 eligibility determination.
Applies to: Qualifying system owners, property classes and refund elections as specified. Relevant passage: “Single-family residential property - 5 kilowatts per system”.
- HSEO — RETITC legislative/implementation update — What changes for 2027 and later systems; details not published on the page.
Document: Act 24 / Executive Order 26-02 update. Effective/source period: Act 24 changes for taxable years after December 31, 2026.
Applies to: Taxpayers seeking RETITC; individual eligibility unresolved here. Relevant passage: “new eligibility requirements, certification provisions, aggregate credit limits, and a future sunset of the credit”.
- Hawaii Executive Order 26-02 — Act 24's retroactive-cap issue and executive implementation clarification.
Document: Executive Order 26-02, pp. 2–3. Effective/source period: Signed June 8, 2026.
Applies to: Administration of RETITC for tax year 2026. Relevant passage: “Clarifying Renewable Energy Technology System Credits in Tax Year 2026”.
- Hawaii DOTAX Tax Information Release 2026-02 — Statewide annual cap, pre-May 21, 2026 exceptions and pending certification process.
Document: TIR 2026-02, pp. 1–2. Effective/source period: July 31, 2026 guidance for 2027 claims on 2026 installations.
Applies to: RETITC claimants; pre-May 21 completion/investment exceptions require qualifying evidence. Relevant passage: “the RETITC annual credit cap will apply to claims made in 2027”.
- Hawaiian Electric Bring Your Own Device Plus — Upfront battery incentive per kW committed and daily two-hour dispatch condition.
Document: Rates and Plan Details; Agreement. Effective/source period: Retrieved September 24, 2026; program approved for 5 years.
Applies to: Hawaiian Electric customers adding a new battery paired with renewable generation. Relevant passage: “This incentive is proportional to the kW committed and is provided once after contract execution.”.
- KIUC — Rooftop Solar FAQs — Kauai is outside Hawaiian Electric's export program.
Document: Rooftop Solar FAQ's: What is Schedule Q?. Effective/source period: Retrieved September 24, 2026; rate changes monthly.
Applies to: Kauai Island Utility Cooperative members; not Hawaiian Electric customers. Relevant passage: “Schedule Q is the program by which KIUC pays you for the excess power you generate.”.
- NLR PVWatts v8 API documentation — Sunlight values for the state input point, Honolulu and Hilo.
Document: PVWatts V8 (GET /api/pvwatts/v8), output field solrad_annual; queries with system_capacity=1, module_type=0, losses=14, array_type=1, tilt=20, azimuth=180, dataset=nsrdb at the state input point (21.112376, −157.485304), Honolulu (21.3069, −157.8583) and Hilo (19.7074, −155.0885); the state request and response are published in /data/state-insolation-pvwatts.json. Effective/source period: PVWatts version 8.5.0 responses, retrieved September 24, 2026.
Applies to: A 1 kW "Fixed - Roof Mounted" array at 20° tilt and 180° azimuth; not a specific roof. Relevant passage: “Annual solar radiation values. (kWh/m2/day)”.
“Source documents checked 2026-09-24” means each linked document was retrieved on that date and the passage quoted under it is the text the claims in this section rely on. The date covers only those claims. It is not a household eligibility decision or a guarantee that a tariff is still current, so check the linked live documents before signing a contract, and report corrections via the contact page.
Reproduce the Hawaii household comparisons
These are hypothetical households, not customer results or offers. All start from an assumed 7 kW array producing 12276.26 kWh in year one; any row that changes production (a battery or a production-stress row) says so. The sunlight input is NSRDB data via PVWatts v8 for one location per state (request and response in state-insolation-pvwatts.json; see the methodology), not a production estimate for your roof. No federal credit is applied. No loan, income-tax effect on incentive revenue, battery replacement or future tariff change is modeled.
The benchmark row prices every kWh at the EIA average cited above. Where another row applies a published figure (for example a tariff or rider rate or charge, a program incentive rate, a statutory fee schedule, or a tax credit's rate, cap or carryforward period), that figure comes from a document in the sources list above. Every other price, consumption share, cost, fee, receipt date and amount of tax a household can use in a year is assumed. Eligibility remains conditional. The annual split does not reproduce monthly netting, time-of-use periods, credit caps, curtailment or minimum bills. Annual fees represent incremental solar costs, not charges you would pay with or without solar.
Production degrades by assumed 0.5% per year. The main result increases both import and export prices by assumed 3% per year; the flat-price column sets that to zero. Neither escalation is a tariff forecast. Fixed fees and scheduled receipts do not escalate. Energy savings accrue uniformly within a year for interpolation; incentives arrive only at year end.
Download exact scenario inputs and all 25 yearly results (JSON)Modeled results, not guarantees. No break-even means no crossing inside 25 years, not a calculated date beyond year 25.| Scenario | Initial cash cost | Year 1 energy value | Year 1 net cash incl. receipts | Payback | Flat-price payback | 25-year net cash after cost |
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| Common retail-value benchmark — no incentives | $22,400.00 | $5,261.61 | $5,261.61 | 4.1 years | 4.3 years | Modeled $156,975.96 |
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| Hypothetical household — no incentives | $22,400.00 | $3,069.07 | $3,069.07 | 6.8 years | 7.4 years | Modeled $82,229.00 |
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| Illustrative battery: assumed cost and higher self-use — no incentives | $32,400.00 | $3,994.51 | $3,994.51 | 7.5 years | 8.3 years | Modeled $103,778.67 |
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| Conditional tax receipt in year 2 | $22,400.00 | $3,069.07 | $3,069.07 | 5.4 years | 5.7 years | Modeled $87,229.00 |
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| Conditional tax receipt in year 3 | $22,400.00 | $3,069.07 | $3,069.07 | 5.4 years | 5.7 years | Modeled $87,229.00 |
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| Conditional tax receipt delayed to year 6 | $22,400.00 | $3,069.07 | $3,069.07 | 6.0 years | 6.0 years | Modeled $87,229.00 |
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| Oahu: published SRE export rates, assumed time-of-day mix — no incentives | $22,400.00 | $1,964.20 | $3,089.69 | 7.0 years | 7.6 years | Modeled $71,074.50 |
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| Oahu: published SRE daytime export rate — no incentives | $22,400.00 | $1,964.20 | $2,958.58 | 7.3 years | 8.0 years | Modeled $67,986.07 |
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| Maui: published SRE daytime export rate — no incentives | $22,400.00 | $1,964.20 | $2,450.34 | 8.6 years | 9.4 years | Modeled $56,014.05 |
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| Hawaii Island: published SRE daytime export rate — no incentives | $22,400.00 | $1,964.20 | $2,744.97 | 7.9 years | 8.4 years | Modeled $62,954.35 |
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| Illustrative 20% lower production — no incentives | $22,400.00 | $2,455.25 | $2,455.25 | 8.3 years | 9.3 years | Modeled $61,303.20 |
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| Illustrative 20% higher production — no incentives | $22,400.00 | $3,682.88 | $3,682.88 | 5.7 years | 6.2 years | Modeled $103,154.80 |
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Inputs, receipts and annual arithmetic: Common retail-value benchmark — no incentives
Historical state-average import value for ALL production; only a comparison, not an address-specific tariff.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 42.860¢/kWh; export 42.860¢/kWh; self-use 100%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(100/100 × 42.86/100) + ((1 − 100/100) × 42.86/100)] = $5,261.61. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: None; no eligibility or benefit assumed. Modeled total receipts inside 25 years: $0.00. These are not subtracted from initial cash cost.
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Hypothetical household — no incentives
Single all-hours 15-cent export sensitivity, escalated with the import price. It is higher than Hawaiian Electric's published 2024–2026 daytime export rates on Oahu, Maui and Hawaii Island, which the island rows below use. Credits lost at the annual true-up and KIUC (Kauai) terms are not modeled.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $3,069.07. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: None; no eligibility or benefit assumed. Modeled total receipts inside 25 years: $0.00. These are not subtracted from initial cash cost.
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Illustrative battery: assumed cost and higher self-use — no incentives
Same 40-cent import and single all-hours 15-cent export prices as the hypothetical household; no battery program incentive or credit is included. The battery is assumed to store 35.90% of production that would otherwise be exported, so that 75% of the energy delivered is used at home instead of 40% of production. An ASSUMED 90% round-trip efficiency is applied to the stored energy: 3.59% of production is lost, so modeled first-year energy is 11835.58 kWh instead of 12276.26 kWh. The added storage cost of 10,000.00 dollars is an assumed sensitivity value, not a quote; with every other input unchanged, an added cost of 5,000.00 dollars gives 6.4 years (7.0 years at flat prices) and 15,000.00 dollars gives 8.5 years (9.6 years at flat prices). No dispatch schedule, time-of-use value, battery degradation, replacement or outage value is modeled.
Assumed initial cash cost $32,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 75%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 11835.58 × [(75/100 × 40/100) + ((1 − 75/100) × 15/100)] = $3,994.51. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: None; no eligibility or benefit assumed. Modeled total receipts inside 25 years: $0.00. These are not subtracted from initial cash cost.
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Conditional tax receipt in year 2
Assumes the owner can actually use a 5,000-dollar credit under the applicable rules. No battery added; installation cost is paid in full initially. Timing comparison (modeled): “Conditional tax receipt in year 2”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt in year 3”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt delayed to year 6”: 6.0 years, 25-year 87,229.00 dollars. All of these rows have the same 25-year total because the model does not discount future dollars: a receipt inside 25 years adds the same amount whenever it arrives. Payback is the same for any receipt that arrives within 5.4 years, the point at which this household would break even if the receipt arrived by the end of year 1; a receipt that arrives later sets payback at the end of the year it arrives, or at the no-receipt break-even (6.8 years) if that comes first. What timing does change is the cash position on the way: this row's cumulative cash is end of year 1 minus 19,330.93 dollars, end of year 2 minus 11,185.60 dollars, end of year 3 minus 7,962.11 dollars, end of year 6 2,197.01 dollars.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $3,069.07. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: Assumed usable tax benefit: 5,000 dollars at year-2 end. Applies only to a system placed in service in 2026 that qualifies: DOTAX TIR 2026-02 (July 31, 2026) says the 40,000,000-dollar aggregate cap from Act 24 applies to 2027 claims for 2026 systems, except systems placed in service before May 21, 2026 or backed by a qualifying payment or cost incurred before that date. Rules for systems placed in service in 2027 are not modeled. Modeled total receipts inside 25 years: $5,000.00. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 2: $5,000.00
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Conditional tax receipt in year 3
Assumes the owner can actually use a 5,000-dollar credit under the applicable rules. No battery added; installation cost is paid in full initially. Timing comparison (modeled): “Conditional tax receipt in year 2”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt in year 3”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt delayed to year 6”: 6.0 years, 25-year 87,229.00 dollars. All of these rows have the same 25-year total because the model does not discount future dollars: a receipt inside 25 years adds the same amount whenever it arrives. Payback is the same for any receipt that arrives within 5.4 years, the point at which this household would break even if the receipt arrived by the end of year 1; a receipt that arrives later sets payback at the end of the year it arrives, or at the no-receipt break-even (6.8 years) if that comes first. What timing does change is the cash position on the way: this row's cumulative cash is end of year 1 minus 19,330.93 dollars, end of year 2 minus 16,185.60 dollars, end of year 3 minus 7,962.11 dollars, end of year 6 2,197.01 dollars.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $3,069.07. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: Assumed usable tax benefit: 5,000 dollars at year-3 end. Applies only to a system placed in service in 2026 that qualifies: DOTAX TIR 2026-02 (July 31, 2026) says the 40,000,000-dollar aggregate cap from Act 24 applies to 2027 claims for 2026 systems, except systems placed in service before May 21, 2026 or backed by a qualifying payment or cost incurred before that date. Rules for systems placed in service in 2027 are not modeled. Modeled total receipts inside 25 years: $5,000.00. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 3: $5,000.00
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Conditional tax receipt delayed to year 6
Same 5,000-dollar credit arriving at the end of year six, for example if a capped claim is delayed or used over several returns. Assumes the owner can use it; no battery added. Timing comparison (modeled): “Conditional tax receipt in year 2”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt in year 3”: 5.4 years, 25-year 87,229.00 dollars; “Conditional tax receipt delayed to year 6”: 6.0 years, 25-year 87,229.00 dollars. All of these rows have the same 25-year total because the model does not discount future dollars: a receipt inside 25 years adds the same amount whenever it arrives. Payback is the same for any receipt that arrives within 5.4 years, the point at which this household would break even if the receipt arrived by the end of year 1; a receipt that arrives later sets payback at the end of the year it arrives, or at the no-receipt break-even (6.8 years) if that comes first. In this row the receipt lands after that point, at the end of year 6, so payback is held to 6.0 years. What timing does change is the cash position on the way: this row's cumulative cash is end of year 1 minus 19,330.93 dollars, end of year 2 minus 16,185.60 dollars, end of year 3 minus 12,962.11 dollars, end of year 6 2,197.01 dollars.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $3,069.07. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: Assumed usable tax benefit: 5,000 dollars at year-6 end. Applies only to a system placed in service in 2026 that qualifies: DOTAX TIR 2026-02 (July 31, 2026) says the 40,000,000-dollar aggregate cap from Act 24 applies to 2027 claims for 2026 systems, except systems placed in service before May 21, 2026 or backed by a qualifying payment or cost incurred before that date. Rules for systems placed in service in 2027 are not modeled. Modeled total receipts inside 25 years: $5,000.00. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 6: $5,000.00
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Oahu: published SRE export rates, assumed time-of-day mix — no incentives
Hawaiian Electric's Smart Renewable Energy Export page publishes “Export rates for 2024-2026”, “updated every 3 years” and “locked in for the first 7 years of any new interconnection agreement”; it also says “any remaining credits left over at the end of the year expire” at the annual true-up. This row assumes the bill absorbs every credit, so none expire. Oahu rates are 18.9 cents overnight (9pm–9am), 13.5 cents daytime (9am–5pm) and 32.9 cents evening peak (5pm–9pm). The export mix is ASSUMED: 80% daytime, 15% overnight (early-morning exports before 9am) and 5% evening peak, giving 15.280 cents; an interval production and load profile would replace it. In this row the 15.280 cents export credit does not rise during the 7-year lock, and after the lock it is ASSUMED to stay at that value, because the later rate is not published. The model escalates its single export-price field together with the import price, so these export credits are entered as year-end receipts and the export field is set to 0: the Year 1 energy value column covers self-used energy only, and the year-one export credit is 1,125.49 dollars on 60% of production. Import 40 cents and 40% self-use are the same assumptions as the hypothetical household; only the import price escalates in the main column. The utility credits exports on the monthly bill, but this model books each year's credits at year end, so payback in this row can be up to one year later than monthly crediting would give and can land on a whole year.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 0.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 0/100)] = $1,964.20. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: No incentive. The listed receipts are export bill credits at the locked 15.280 cents rate on 60% of modeled production, not a program payment; no eligibility is verified. Modeled total receipts inside 25 years: $26,511.94. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 1: $1,125.49
- Assumed receipt at end of year 2: $1,119.86
- Assumed receipt at end of year 3: $1,114.26
- Assumed receipt at end of year 4: $1,108.69
- Assumed receipt at end of year 5: $1,103.15
- Assumed receipt at end of year 6: $1,097.63
- Assumed receipt at end of year 7: $1,092.14
- Assumed receipt at end of year 8: $1,086.68
- Assumed receipt at end of year 9: $1,081.25
- Assumed receipt at end of year 10: $1,075.84
- Assumed receipt at end of year 11: $1,070.46
- Assumed receipt at end of year 12: $1,065.11
- Assumed receipt at end of year 13: $1,059.79
- Assumed receipt at end of year 14: $1,054.49
- Assumed receipt at end of year 15: $1,049.21
- Assumed receipt at end of year 16: $1,043.97
- Assumed receipt at end of year 17: $1,038.75
- Assumed receipt at end of year 18: $1,033.55
- Assumed receipt at end of year 19: $1,028.39
- Assumed receipt at end of year 20: $1,023.24
- Assumed receipt at end of year 21: $1,018.13
- Assumed receipt at end of year 22: $1,013.04
- Assumed receipt at end of year 23: $1,007.97
- Assumed receipt at end of year 24: $1,002.93
- Assumed receipt at end of year 25: $997.92
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Oahu: published SRE daytime export rate — no incentives
Hawaiian Electric's Smart Renewable Energy Export page publishes “Export rates for 2024-2026”, “updated every 3 years” and “locked in for the first 7 years of any new interconnection agreement”; it also says “any remaining credits left over at the end of the year expire” at the annual true-up. This row assumes the bill absorbs every credit, so none expire. Oahu's daytime (9am–5pm) rate, 13.5 cents, is applied to every export; overnight (18.9 cents) and evening-peak (32.9 cents) exports would earn more, which the mixed row above tests. In this row the 13.500 cents export credit does not rise during the 7-year lock, and after the lock it is ASSUMED to stay at that value, because the later rate is not published. The model escalates its single export-price field together with the import price, so these export credits are entered as year-end receipts and the export field is set to 0: the Year 1 energy value column covers self-used energy only, and the year-one export credit is 994.38 dollars on 60% of production. Import 40 cents and 40% self-use are the same assumptions as the hypothetical household; only the import price escalates in the main column. The utility credits exports on the monthly bill, but this model books each year's credits at year end, so payback in this row can be up to one year later than monthly crediting would give and can land on a whole year.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 0.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 0/100)] = $1,964.20. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: No incentive. The listed receipts are export bill credits at the locked 13.500 cents rate on 60% of modeled production, not a program payment; no eligibility is verified. Modeled total receipts inside 25 years: $23,423.51. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 1: $994.38
- Assumed receipt at end of year 2: $989.41
- Assumed receipt at end of year 3: $984.46
- Assumed receipt at end of year 4: $979.54
- Assumed receipt at end of year 5: $974.64
- Assumed receipt at end of year 6: $969.77
- Assumed receipt at end of year 7: $964.92
- Assumed receipt at end of year 8: $960.09
- Assumed receipt at end of year 9: $955.29
- Assumed receipt at end of year 10: $950.51
- Assumed receipt at end of year 11: $945.76
- Assumed receipt at end of year 12: $941.03
- Assumed receipt at end of year 13: $936.33
- Assumed receipt at end of year 14: $931.65
- Assumed receipt at end of year 15: $926.99
- Assumed receipt at end of year 16: $922.35
- Assumed receipt at end of year 17: $917.74
- Assumed receipt at end of year 18: $913.15
- Assumed receipt at end of year 19: $908.59
- Assumed receipt at end of year 20: $904.04
- Assumed receipt at end of year 21: $899.52
- Assumed receipt at end of year 22: $895.03
- Assumed receipt at end of year 23: $890.55
- Assumed receipt at end of year 24: $886.10
- Assumed receipt at end of year 25: $881.67
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Maui: published SRE daytime export rate — no incentives
Hawaiian Electric's Smart Renewable Energy Export page publishes “Export rates for 2024-2026”, “updated every 3 years” and “locked in for the first 7 years of any new interconnection agreement”; it also says “any remaining credits left over at the end of the year expire” at the annual true-up. This row assumes the bill absorbs every credit, so none expire. Maui's daytime (9am–5pm) rate, 6.6 cents, is applied to every export; overnight (13.1 cents) and evening-peak (18.2 cents) exports would earn more. In this row the 6.600 cents export credit does not rise during the 7-year lock, and after the lock it is ASSUMED to stay at that value, because the later rate is not published. The model escalates its single export-price field together with the import price, so these export credits are entered as year-end receipts and the export field is set to 0: the Year 1 energy value column covers self-used energy only, and the year-one export credit is 486.14 dollars on 60% of production. Import 40 cents and 40% self-use are the same assumptions as the hypothetical household; only the import price escalates in the main column. The utility credits exports on the monthly bill, but this model books each year's credits at year end, so payback in this row can be up to one year later than monthly crediting would give and can land on a whole year.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 0.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 0/100)] = $1,964.20. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: No incentive. The listed receipts are export bill credits at the locked 6.600 cents rate on 60% of modeled production, not a program payment; no eligibility is verified. Modeled total receipts inside 25 years: $11,451.49. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 1: $486.14
- Assumed receipt at end of year 2: $483.71
- Assumed receipt at end of year 3: $481.29
- Assumed receipt at end of year 4: $478.88
- Assumed receipt at end of year 5: $476.49
- Assumed receipt at end of year 6: $474.11
- Assumed receipt at end of year 7: $471.74
- Assumed receipt at end of year 8: $469.38
- Assumed receipt at end of year 9: $467.03
- Assumed receipt at end of year 10: $464.70
- Assumed receipt at end of year 11: $462.37
- Assumed receipt at end of year 12: $460.06
- Assumed receipt at end of year 13: $457.76
- Assumed receipt at end of year 14: $455.47
- Assumed receipt at end of year 15: $453.19
- Assumed receipt at end of year 16: $450.93
- Assumed receipt at end of year 17: $448.67
- Assumed receipt at end of year 18: $446.43
- Assumed receipt at end of year 19: $444.20
- Assumed receipt at end of year 20: $441.98
- Assumed receipt at end of year 21: $439.77
- Assumed receipt at end of year 22: $437.57
- Assumed receipt at end of year 23: $435.38
- Assumed receipt at end of year 24: $433.20
- Assumed receipt at end of year 25: $431.04
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Hawaii Island: published SRE daytime export rate — no incentives
Hawaiian Electric's Smart Renewable Energy Export page publishes “Export rates for 2024-2026”, “updated every 3 years” and “locked in for the first 7 years of any new interconnection agreement”; it also says “any remaining credits left over at the end of the year expire” at the annual true-up. This row assumes the bill absorbs every credit, so none expire. Hawaii Island's daytime (9am–5pm) rate, 10.6 cents, is applied to every export; overnight (14.8 cents) and evening-peak (23.1 cents) exports would earn more. In this row the 10.600 cents export credit does not rise during the 7-year lock, and after the lock it is ASSUMED to stay at that value, because the later rate is not published. The model escalates its single export-price field together with the import price, so these export credits are entered as year-end receipts and the export field is set to 0: the Year 1 energy value column covers self-used energy only, and the year-one export credit is 780.77 dollars on 60% of production. Import 40 cents and 40% self-use are the same assumptions as the hypothetical household; only the import price escalates in the main column. The utility credits exports on the monthly bill, but this model books each year's credits at year end, so payback in this row can be up to one year later than monthly crediting would give and can land on a whole year.
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 0.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 12276.26 × [(40/100 × 40/100) + ((1 − 40/100) × 0/100)] = $1,964.20. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: No incentive. The listed receipts are export bill credits at the locked 10.600 cents rate on 60% of modeled production, not a program payment; no eligibility is verified. Modeled total receipts inside 25 years: $18,391.79. These are not subtracted from initial cash cost.
- Assumed receipt at end of year 1: $780.77
- Assumed receipt at end of year 2: $776.87
- Assumed receipt at end of year 3: $772.98
- Assumed receipt at end of year 4: $769.12
- Assumed receipt at end of year 5: $765.27
- Assumed receipt at end of year 6: $761.45
- Assumed receipt at end of year 7: $757.64
- Assumed receipt at end of year 8: $753.85
- Assumed receipt at end of year 9: $750.08
- Assumed receipt at end of year 10: $746.33
- Assumed receipt at end of year 11: $742.60
- Assumed receipt at end of year 12: $738.89
- Assumed receipt at end of year 13: $735.19
- Assumed receipt at end of year 14: $731.52
- Assumed receipt at end of year 15: $727.86
- Assumed receipt at end of year 16: $724.22
- Assumed receipt at end of year 17: $720.60
- Assumed receipt at end of year 18: $716.99
- Assumed receipt at end of year 19: $713.41
- Assumed receipt at end of year 20: $709.84
- Assumed receipt at end of year 21: $706.29
- Assumed receipt at end of year 22: $702.76
- Assumed receipt at end of year 23: $699.25
- Assumed receipt at end of year 24: $695.75
- Assumed receipt at end of year 25: $692.27
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Illustrative 20% lower production — no incentives
Same prices, self-use share and cost as the hypothetical household, with first-year production 9821.01 kWh instead of 12276.26 kWh. Roof direction, shading and location within the state can move production by this much. At the same production the retail-value benchmark gives 5.1 years (5.4 years at flat prices).
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 9821.01 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $2,455.25. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: None; no eligibility or benefit assumed. Modeled total receipts inside 25 years: $0.00. These are not subtracted from initial cash cost.
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Inputs, receipts and annual arithmetic: Illustrative 20% higher production — no incentives
Same prices, self-use share and cost as the hypothetical household, with first-year production 14731.52 kWh instead of 12276.26 kWh. Roof direction, shading and location within the state can move production by this much. At the same production the retail-value benchmark gives 3.4 years (3.6 years at flat prices).
Assumed initial cash cost $22,400.00, not reduced by any upfront credit or rebate; any receipt is listed below and arrives at year end. Import 40.000¢/kWh; export 15.000¢/kWh; self-use 40%; incremental fixed annual cost $0.00.
Year-one modeled energy value = 14731.52 × [(40/100 × 40/100) + ((1 − 40/100) × 15/100)] = $3,682.88. Subtract the annual fixed cost and add only that year's receipts for net cash. Display rounds cents; the downloadable calculation retains full precision.
Incentive basis: None; no eligibility or benefit assumed. Modeled total receipts inside 25 years: $0.00. These are not subtracted from initial cash cost.
The exact input fields and all 25 modelled years for this row are in the JSON download above.
Formula and modeling limitations · Use the editable calculator below to test your own cash price and energy split. It cannot confirm utility enrollment or tax eligibility.