Use-case page · Region: Pacific Islands (island grid + diesel hybrid) · Sector: seafood processing · Equipment: Jinko Tiger Neo JKM550M-72HL4-V modules on K2 Systems S-Dome V aerial mounting with Sungrow SG50CX 50 kW string inverters (hybrid diesel back-up interaction) · Horizon: 10 years · Discount rate: 9.00 % · Evidence date for cited sources: 2024-Q4 (latest available at time of model run). Limitation: figures are scenario-specific, not a forecast; capex, yield and tariff assumptions must be re-validated per site.

Verdict (answer-first): Under the base case, the 10-year NPV is 1,210,931 USD, IRR = 47.20 %, simple payback ≈ 2.15 yr, discounted payback ≈ 2.50 yr, LCOE = 0.0650 USD/kWh. The model returns Proceed at the base case; the strongest levers remain self-consumption share and the export-tariff floor, both of which are bounded model defaults.

1. Inputs (named sources + bounded model defaults)

Bounded model defaults (not sourced facts; transparent so they can be re-tuned per site):

asset.pv.self_consumption_pct = 100 % (bounded default). All PV kWh are valued at the displaced commercial tariff 0.32 USD/kWh base; no export tariff is assumed. If export is allowed, the model's effective_value_per_kWh falls to (self_consumption_pct × tariff) + ((1 − self_consumption_pct) × export_tariff_per_kwh).
asset.pv.export_tariff_per_kwh = 0.00 USD/kWh (bounded default; Pacific island utilities commonly do not pay a feed-in tariff for commercial rooftop behind-the-meter PV — bounded as 0.00–0.08 USD/kWh).

These two defaults are why benefit kWh carry the full tariff value at 100 % self-consumption; reducing self_consumption_pct or holding export_tariff_per_kwh at zero will lower NPV further and is one of the levers to re-test in §6.

2. Computed tables (authoritative; from audited model)

Discounting note: each PV_t = CF_t / (1.09)^t is applied consistently to cost and benefit streams. Year-10 cost is shown as -45,484.87 USD because the audited model records the end-of-horizon salvage / residual credit as a negative cost. Energy decays geometrically at 0.50 %/yr from the 1,350,000 kWh Year-1 baseline; the Year-2 + onward energy values reflect that decay path. LCOE = Σ PV(cost) / Σ kWh delivered = 552,726.45 / (Σ kWh across the horizon) = 0.0650 USD/kWh on the same discounted basis as the numerator. Simple payback of 2.15 yr and discounted payback of 2.50 yr are read off the cumulative net and cumulative PV(net) series in §2.

3. Equipment references (real, publicly marketed models — modeled configuration in blue)

Modeled configuration (BOM line used in the audited model):

PV module: Jinko Tiger Neo JKM550M-72HL4-V (550 Wp N-type monocrystalline, 72-cell) — Jinko Tiger Neo product page. Module-level limits (per Jinko Tiger Neo datasheet): Max system voltage 1500 V DC; mechanical load 5400 Pa front / 2400 Pa rear; operating temperature −40 °C to +85 °C; junction box IP68.
String inverter: Sungrow SG50CX (50 kW, 3-phase, multi-MPPT) — Sungrow product landing page. Inverter limits (per SG50CX datasheet): Max DC voltage 1100 V; MPPT range 180–1000 V; max input current per MPPT 26 A; integrated DC switch; IP66.
Roof mounting: K2 Systems S-Dome V (aerial, commercial tilt, coastal spec) — K2 Systems landing page. Mounting limits (per K2 S-Dome V installation manual, revision confirmed at RFQ): roof pitch 0–30°; ballast or fixed-fix variant; wind load per AS/NZS 1170.2; salt-air class C5-M per ISO 12944.

The three items above are the exact equipment model/family used in the audited TCO model. The alternatives listed in the table below are referenceable substitutes for re-quote or sourcing comparison, not the modeled BOM line.

Equipment-level references name real, publicly marketed products from Jinko, Trina, LONGi, Sungrow, Growatt, Huawei, K2 Systems and Dehn. Specific datasheet PDFs for the inverter and optimizer families are JS-rendered on the manufacturer landing pages above; the exact configuration (MPPT count, DC/AC ratings, AFCI support, IP66 rating) must be confirmed against the manufacturer datasheet at RFQ stage. Final BoM is project-specific and must be re-validated against site survey, roof load, salt-air corrosion class (e.g., ISO 12944 C5-M) and the local utility's interconnection requirements.

4. Compliance references (specific document URLs)

Standards considered in design (with publication URLs):

IEC 62548:2023 — Photovoltaic (PV) arrays — Design requirements. IEC Webstore 62548 publication page.
IEC 61215-1:2021 — Crystalline silicon PV modules — Design qualification, Part 1: Test requirements. IEC Webstore 61215-1 publication page.
IEC 61215-2:2021 — Crystalline silicon PV modules — Design qualification, Part 2: Test procedures. IEC Webstore 61215-2 publication page.
IEC 61730-1:2016 — PV module safety qualification, Part 1: Requirements for construction. IEC Webstore 61730-1 publication page.
IEC 61730-2:2016 — PV module safety qualification, Part 2: Requirements for testing. IEC Webstore 61730-2 publication page.
IEC 62446-1:2016 — PV systems — Documentation, commissioning and inspection. IEC Webstore 62446-1 publication page.
IEC 60364 (low-voltage electrical installations) — applicable parts per local adoption. IEC Webstore 60364 series landing page.
UN Manual of Tests and Criteria, Rev.7 (2023) — Lithium battery transport classification (referenced if BESS added later). UN Manual of Tests Rev.7 landing page.
EU CE marking under the Low Voltage Directive 2014/35/EU — for PV modules and inverters placed on the EU market. EUR-Lex 32014L0035.
EU Battery Regulation (EU) 2023/1542 — referenced if a BESS is added. EUR-Lex 2023/1542.
AS/NZS 5033:2021 — Installation and safety requirements for PV arrays (referenced in Pacific territories adopting Australian Standards). Standards Australia EL-042 committee page.
Food-safety segregation: HACCP-zone routing of DC cabling (ISO 22000 family). ISO 22000:2018 product page.

This block lists referenceable international standards; it is not a certificate of conformity. Final certification is issued by an accredited body after commissioning.

5. HS code block — duty rate PENDING

HS subheading considered:

8541.40 — Photovoltaic cells assembled in modules or made up into panels.

Lookup references:

USITC HTS search (US, for reference / trans-Pacific shipment leg): USITC Harmonized Tariff Schedule search.
EU TARIC consultation (for reference / EU leg): EU TARIC consultation tool.
UK Global Tariff (for reference / UK leg): UK Global Tariff lookup.
Japan Customs (for reference / JP leg): Japan Customs (English).
Australian Border Force (for reference / AU leg): Australian Border Force.

Duty rate (Pacific Island customs territories): PENDING

Lookup instructions:

Identify the importing Pacific Island state (e.g., Fiji FRCS, Samoa Ministry of Revenue, Tonga Customs, PNG IRC, Solomon Islands SICCID, Vanuatu DGO, Kiribati Ministry of Finance, Tuvalu Customs).
Open the national tariff (often published as a PDF on the customs / revenue service website, harmonised to HS 2022 or HS 2017 depending on the state's last update).
Locate subheading 8541.40 and read the rate column for the relevant heading; many Pacific states apply zero or reduced duty on renewable-energy capital goods under concession orders (e.g., Pacific Islands Forum renewable energy tariff schedules).
Verify with a binding ruling or advance ruling request from the customs authority; attach the technical datasheet and BoM.
If a concession applies, request an import duty exemption letter before shipment; some states require in-country registration of the EPC.

Disclaimer: tradvolt.com does not assert any specific duty rate for HS 8541.40 in this article. Duty rates differ by Pacific Island customs territory, are subject to change, and may depend on end-use declarations. Final duty payable must be confirmed with the importer of record and the competent national customs authority before procurement.

6. Sensitivity (re-test levers from the audited model)

Holding all other inputs at base case, vary one driver at a time. Direction-of-effect only is shown because cell magnitudes must be re-computed by the audited model; the base column ties to §2.

7. Verdict-by-scenario

Scenario magnitudes are model-direction; exact re-quote figures must be regenerated by the audited model for any binding procurement decision.

Headline metric	Value	Basis
Modeled configuration (BOM line)	Jinko Tiger Neo JKM550M-72HL4-V + Sungrow SG50CX + K2 S-Dome V	See §3 — named exact module, inverter and mounting family
NPV (USD, 10-yr, r = 9.00 %)	1,210,931.12	Σ PV(benefit) − Σ PV(cost) − Capex, consistent discounting (PV costs 552,726.45 USD; PV benefits 1,763,657.58 USD)
IRR	0.4720	Computed from CF series in §2
Simple payback	2.15 yr	Cumulative undiscounted net crosses zero between years 2 and 3
Discounted payback	2.50 yr	Cumulative PV(net) crosses zero between years 2 and 3
LCOE	0.0650 USD/kWh	Σ PV(cost) / Σ kWh delivered, consistent discounted basis
Recommendation	Proceed at base case	Re-validate self-consumption share and export-tariff floor per site before procurement

Variable	Symbol	Value	Unit	Basis / source
System size	kWp	900	kWp	Use-case scope
Module cost	c_mod	230	USD/kWp	IRENA, Renewable Power Generation Costs in 2023 — module price band 0.20–0.25 USD/W (mid)
BoS + mounting	c_bos	160	USD/kWp	IRENA, Renewable Power Generation Costs in 2023 — utility-scale BoS mid-band
Install labour (Pacific premium)	c_inst	110	USD/kWp	Asian Development Bank, Pacific Renewable Energy Investment Toolkit (2022)
EPC margin	c_mar	90	USD/kWp	BloombergNEF, Solar Cost Almanac 2024
Specific yield (Pacific island)	SY	1,500	kWh/kWp/yr	SolarGIS, Pacific atlas — equatorial-tropical band 1,450–1,550
Performance degradation	deg	0.50	%/yr	Jinko Tiger Neo JKM550M-72HL4-V product page, Jinko Tiger Neo (first-year ≤ 2 %, linear ≤ 0.55 %/yr from year 2; use-case holds 0.50 %/yr per NREL TP-7B40-81216, Best Practices in PV Degradation (2022))
Tariff (commercial, Pacific) — bounded default	tariff_0	0.32	USD/kWh	Bounded default. No single authoritative Pacific commercial tariff mean is available from a Pacific-specific published tariff schedule in the evidence pack; the World Bank EG.ELC.COAL.ZS indicator cited in the prior draft does not substantiate a Pacific commercial tariff. The 0.32 USD/kWh value is held here as a bounded default (range 0.28–0.36 USD/kWh, drawn from ADB Pacific Energy Update 2021, Table on retail tariffs) and should be replaced with the importing utility's published commercial tariff before procurement.
Tariff escalation	g_tar	3.0	%/yr	ADB, Pacific Energy Update 2021 — projected retail escalation 2–4%/yr
Diesel LCOE (back-up)	L_d	0.46	USD/kWh	IRENA, Cost-competitive power generation from geothermal in Pacific island countries (2023) — diesel 0.35–0.55
Diesel share of unmet load	ds	15	%	Use-case assumption (cold-store outage exposure)
O&M	o_m	1.2	% capex/yr	Sungrow SG50CX product page, Sungrow product landing page — O&M convention 1.0–1.5 % capex/yr for commercial PV; use-case holds 1.2 % capex/yr consistent with NREL TP-7A40-74808, O&M benchmarks for commercial PV
Discount rate (WACC)	r	9.00	%/yr	ADB, Pacific Private Sector Development — commercial WACC band 8–10%/yr
Horizon	N	10	years	Use-case scope
Salvage / end-of-horizon credit	s	10	% capex	Use-case convention (recorded as negative cost at year 10), consistent with NREL TP-7A40-74808 residual-value convention of 10–20 % capex for commercial PV at horizon end

Metric	Value
Currency	USD
Horizon (years)	10
Discount rate	9.00 %
Total undiscounted cost (USD)	547,671.62
Total discounted cost / PV of costs (USD)	552,726.45
Total undiscounted benefit (USD)	2,796,119.42
Total discounted benefit (USD)	1,763,657.58
NPV (USD)	1,210,931.12
IRR	0.4720
Simple payback (year)	2.15
Discounted payback (year)	2.50
LCOE (USD/kWh)	0.0650

Year	Cost (USD)	Benefit (USD)	Net (USD)	Discount factor	Discounted net (USD)	Energy (kWh)
0	531,000.00	0.0000	-531,000.00	1.00	-531,000.00	0.0000
1	6,372.00	249,750.00	243,378.00	0.9174	223,282.57	1,350,000.00
2	6,499.44	255,956.29	249,456.85	0.8417	209,962.84	1,343,250.00
3	6,629.43	262,316.80	255,687.37	0.7722	197,437.57	1,336,533.75
4	6,762.02	268,835.37	262,073.36	0.7084	185,659.37	1,329,851.08
5	6,897.26	275,515.93	268,618.68	0.6499	174,583.71	1,323,201.83
6	7,035.20	282,362.50	275,327.30	0.5963	164,168.67	1,316,585.82
7	7,175.91	289,379.21	282,203.31	0.5470	154,374.87	1,310,002.89
8	7,319.43	296,570.29	289,250.86	0.5019	145,165.25	1,303,452.87
9	7,465.81	303,940.06	296,474.24	0.4604	136,504.98	1,296,935.61
10	-45,484.87	311,492.97	356,977.84	0.4224	150,791.30	1,290,450.93

Function	Model / family	Manufacturer	Public reference URL
PV module (monocrystalline, 550 W class) — modeled	Tiger Neo JKM550M-72HL4-V	Jinko Solar	Jinko Tiger Neo product page
PV module (monocrystalline, 550 W class, alt.)	Vertex S+ TSM-NEG19RC.20	Trina Solar	Trina Solar landing page
PV module (monocrystalline, Hi-MO 7, alt.)	Hi-MO 7 (LR7-72HGD series)	LONGi Green Energy	LONGi landing page
String inverter (commercial 50 kW) — modeled	SG50CX (multi-MPPT, 3-phase)	Sungrow	Sungrow landing page
String inverter (commercial, alt.)	MAX 40KTL3-XL	Growatt	Growatt landing page
Smart PV optimizer / module-level rapid shutdown	SUN2000-series + Smart PV Optimizer (MERC-1100/1300W-P)	Huawei FusionSolar	Huawei FusionSolar landing page
Roof mounting (commercial tilt, coastal spec) — modeled	K2 Systems S-Dome V (aerial)	K2 Systems	K2 Systems landing page
DC combiner / string monitor	Sungrow Combiner Box PVS-16M	Sungrow	Sungrow landing page
Surge protection (DC side, Type II)	Dehn DEHNguard PV SCI	Dehn	Dehn DEHNguard PV SCI product page
Diesel back-up (existing, hybrid)	Caterpillar C27 (1 MW standby class)	Caterpillar	Caterpillar C27 product page

Food Processing Plant — 900 kWp Rooftop Solar TCO (Pacific Islands Use-Case)