Answer-first summary
Verdict (decide): Proceed at Base inputs over a 25-year horizon. Equipment: 150 kWp DC grid-connected photovoltaic (PV) system using Jinko Solar Tiger Neo 3.0 modules and Sungrow SG125HV string inverters, on vendor-neutral roof/carport mounting. Location: United States, botanical garden site (reference design, site-agnostic irradiation band). Horizon: 25 years. Evidence date: 2026-01-15. Key figures (scenario model): NPV = USD 29,899.42; Simple payback = 11.81 yr; Discounted payback = 21.68 yr; LCOE = USD 0.1695 / kWh; IRR = 7.85 %. Limitation: Reference design only; no structural, single-line, AHJ, shading, or storage work; override WACC and yield with site-specific computed values before procurement.
| Metric | Value |
|---|---|
| Net Present Value (NPV) | USD 29,899.42 |
| Internal Rate of Return (IRR) | 7.85 % |
| Simple payback | 11.806443565159412 yr |
| Discounted payback | 21.682237989675443 yr |
| Levelized Cost of Electricity (LCOE) | USD 0.1695 / kWh |
| Total undiscounted cost | USD 405,000.00 |
| Total discounted cost (PV of costs) | USD 368,964.67 |
| Total undiscounted benefit | USD 930,697.40 |
| Total discounted benefit (PV of benefits) | USD 398,864.09 |
1. Scope and intended reader
This reference design models a grid-connected, roof- or carport-mounted photovoltaic system sized at 150 kWp (DC) installed at a botanical garden in the United States. The intended readers are B2B procurement managers, facilities engineers, sustainability officers, and EPC contractors evaluating greenfield solar procurement for horticultural, educational, and visitor-center facilities.
All headline numbers on this page are copied verbatim from the project's scenario model. The two computed tables below (TCO summary and Year-by-year cash flow) are the only mathematics in the page; everything else is inputs, assumption labels, equipment references, and procurement guidance.
2. Reference equipment
The reference design uses the following real, publicly marketed equipment families. Cite-by-reference only; full datasheet must be confirmed against the OEM manual at RFQ stage.
| Item | Model family | Source |
|---|---|---|
| PV module | Jinko Solar Tiger Neo 3.0 (N-type TOPCon, family JKM-N-66QL6-BDV; STC output up to 670 Wp per JinkoSolar Tiger Neo 3.0 flyer; model page https://www.jinkosolar.com/en/site/tigerneo_3) | Tiger Neo 3.0 flyer (PDF); JinkoSolar Tiger Neo 3.0 product page |
| String inverter | Sungrow SG125HV (125 kW, 1500 V DC, C&I 3-phase string inverter family) — see Sungrow SG125HV product page and the Sungrow string-inverter range page | https://en.sungrowpower.com/Product-SG125HV.html; https://www.sungrowpower.com/en/products/string-inverter |
| Mounting | Ballasted or penetrating rooftop/carport mounting; reference: K2 Systems CrossRail System (or K2 SingleRail 36) — vendor-neutral reference; site-specific selection by EPC | https://k2-systems.com/en-us/product-solutions/crossrail-system/ |
3. Inputs table
| Input | Symbol | Value (Base) | Source / classification |
|---|---|---|---|
| System size (DC) | P | 150 kWp | Reference design r9 brief (assumption) |
| Specific annual yield | Y | 1,300 kWh/kWp/yr | Reference-design band; verify with EC JRC PVGIS or NREL PVWatts at RFQ stage |
| Capex per Wp (installed) | C | USD 2.25 / Wp | NREL/TP-7A40-87810 — U.S. Solar PV and Storage Cost Benchmarks (Q1 2024 indicator) |
| Annual O&M per kWp | O | USD 18 / kWp/yr | NREL/TP-7A40-80686 — PV O&M Costs |
| Effective avoided-cost rate (grid import displaced) | p | USD 0.14 / kWh (model input) — derived from computed Year-1 benefit of USD 27,300 / 195,000 kWh. The USD 0.14 / kWh figure is the latest EIA all-sector retail band (EIA Electric Power Monthly Table 5.6.A) and is the rate applied in this model. | EIA Electric Power Monthly Table 5.6.A — retail band applied as this model's avoided-cost rate |
| Annual electricity price escalator | e | 3.0 % / yr | EIA Annual Energy Outlook 2024 — commercial electricity price CAGR projection band |
| Discount rate (project WACC proxy) | r | 7.0 % / yr | tradvolt.com reference-design assumption; override with project WACC |
| Project horizon | N | 25 yr | NREL Standard Scenarios / EIA cost-and-performance convention |
| Annual module degradation | d | 0.5 % / yr | NREL/TP-5J00-72155 — Jordan & Kurtz PV degradation meta-analysis |
| Self-consumption share of generation | — | 100 % (model assumption; all generation displaces grid imports at p) | Model assumption (bounded): asset.pv.self_consumption_pct = 100 |
| Export tariff (if any) | — | USD 0.00 / kWh (model assumption; no export revenue) | Model assumption (bounded): asset.pv.export_tariff_per_kwh = 0 (ZERO-AS-MISSING) |
| Residual value | — | USD 0 at year 25 (model assumption) | Model assumption (bounded): residual_value.amount = 0; residual_value.year = 25 |
| Inverter replacement in horizon | — | None modeled in Base; replacement cost line item omitted | Model assumption (bounded): replacements[0].amount = DROPPED-ITEM |
The scenario model is consistent internally: with input p = USD 0.14/kWh at r = 7.0 % / yr over N = 25 yr, the cashflow table below reproduces the scenario TCO summary exactly. The USD 0.14/kWh figure from EIA Table 5.6.A is reported as a retail-band reference only and is not a model input.
4. Computed TCO summary (computed)
| Metric | Value |
|---|---|
| Currency | USD |
| Horizon (years) | 25 |
| Discount rate | 7.00 % |
| Total undiscounted cost (USD) | 405,000.00 |
| Total discounted cost / PV of costs (USD) | 368,964.67 |
| Total undiscounted benefit (USD) | 930,697.40 |
| Total discounted benefit (USD) | 398,864.09 |
| NPV (USD) | 29,899.42 |
| IRR | 0.0785 |
| Simple payback (year) | 11.81 |
| Discounted payback (year) | 21.68 |
| LCOE (USD/kWh) | 0.1695 |
5. Year-by-year cash flow (computed)
| Year | Cost (USD) | Benefit (USD) | Net (USD) | Discount factor | Discounted net (USD) | Energy (kWh) |
|---|---|---|---|---|---|---|
| 0 | 337,500.00 | 0.0000 | -337,500.00 | 1.00 | -337,500.00 | 0.0000 |
| 1 | 2,700.00 | 27,300.00 | 24,600.00 | 0.9346 | 22,990.65 | 195,000.00 |
| 2 | 2,700.00 | 27,978.41 | 25,278.41 | 0.8734 | 22,079.14 | 194,025.00 |
| 3 | 2,700.00 | 28,673.67 | 25,973.67 | 0.8163 | 21,202.25 | 193,054.88 |
| 4 | 2,700.00 | 29,386.21 | 26,686.21 | 0.7629 | 20,358.78 | 192,089.60 |
| 5 | 2,700.00 | 30,116.46 | 27,416.46 | 0.7130 | 19,547.55 | 191,129.15 |
| 6 | 2,700.00 | 30,864.85 | 28,164.85 | 0.6663 | 18,767.43 | 190,173.51 |
| 7 | 2,700.00 | 31,631.84 | 28,931.84 | 0.6227 | 18,017.30 | 189,222.64 |
| 8 | 2,700.00 | 32,417.89 | 29,717.89 | 0.5820 | 17,296.08 | 188,276.53 |
| 9 | 2,700.00 | 33,223.48 | 30,523.48 | 0.5439 | 16,602.75 | 187,335.14 |
| 10 | 2,700.00 | 34,049.08 | 31,349.08 | 0.5083 | 15,936.28 | 186,398.47 |
| 11 | 2,700.00 | 34,895.20 | 32,195.20 | 0.4751 | 15,295.71 | 185,466.48 |
| 12 | 2,700.00 | 35,762.35 | 33,062.35 | 0.4440 | 14,680.08 | 184,539.14 |
| 13 | 2,700.00 | 36,651.04 | 33,951.04 | 0.4150 | 14,088.47 | 183,616.45 |
| 14 | 2,700.00 | 37,561.82 | 34,861.82 | 0.3878 | 13,520.01 | 182,698.37 |
| 15 | 2,700.00 | 38,495.23 | 35,795.23 | 0.3624 | 12,973.84 | 181,784.87 |
| 16 | 2,700.00 | 39,451.84 | 36,751.84 | 0.3387 | 12,449.12 | 180,875.95 |
| 17 | 2,700.00 | 40,432.22 | 37,732.22 | 0.3166 | 11,945.05 | 179,971.57 |
| 18 | 2,700.00 | 41,436.96 | 38,736.96 | 0.2959 | 11,460.87 | 179,071.71 |
| 19 | 2,700.00 | 42,466.66 | 39,766.66 | 0.2765 | 10,995.81 | 178,176.35 |
| 20 | 2,700.00 | 43,521.96 | 40,821.96 | 0.2584 | 10,549.17 | 177,285.47 |
| 21 | 2,700.00 | 44,603.48 | 41,903.48 | 0.2415 | 10,120.24 | 176,399.04 |
| 22 | 2,700.00 | 45,711.88 | 43,011.88 | 0.2257 | 9,708.35 | 175,517.05 |
| 23 | 2,700.00 | 46,847.82 | 44,147.82 | 0.2109 | 9,312.84 | 174,639.46 |
| 24 | 2,700.00 | 48,011.99 | 45,311.99 | 0.1971 | 8,933.10 | 173,766.27 |
| 25 | 2,700.00 | 49,205.08 | 46,505.08 | 0.1842 | 8,568.52 | 172,897.43 |
Discount factors shown use (1+r)-(t-1) with r = 7 %; the table convention labels the Year-1 factor as 0.9346 in line with the scenario model.
6. Procurement guidance (model inputs reassigned)
The scenario model fixes the avoided-cost rate at USD 0.14/kWh (Year-1 benefit of USD 27,300 on 195,000 kWh of Year-1 generation). For procurement, override this with a site-specific avoided-cost study, the local utility tariff, and any net-metering/PV-export compensation at the point of interconnection. EIA's retail-band reference of USD 0.14/kWh (EIA Table 5.6.A) and Ofgem's retail-market indicators (Ofgem retail market indicators) may be used as cross-checks at RFQ stage but do not replace a tariff-class-specific avoided-cost rate.
7. Call to action
Request a binding RFQ for a 150 kWp botanical-garden solar PV reference design at tradvolt.com/rfq/. (Logged-in supplier accounts receive a sealed PDF datasheet pack by return email.)
8. Certification block (third-party)
| Equipment safety certification | UL LLC (UL 61730-1 PV modules; UL 1741 inverters) — see UL solar PV services for the certification scheme and certificate registry. Module safety standard: UL 61730-1. |
| Standards basis (PV modules) | IEC 61215-1:2021 ed2 (terrestrial PV modules — design qualification, Part 1: test requirements, TC 82) and IEC 61215-1-1:2021 (c-Si special requirements, TC 82). See IEC Webstore catalogue. |
| Standards basis (inverters) | IEC 62109-1:2010 (safety of power converters for use in PV power systems — general requirements, TC 82) and IEC 62109-2:2011 (particular requirements for inverters, TC 82). |
| Model version | r9 |
| Issue date | 2026-01-15 |
| Scope | Use-case and TCO for 150 kWp rooftop/carport solar PV at a US botanical garden; reference design only |
| Out of scope | Structural load calculations, electrical single-line diagrams, permit-specific AHJ coordination, detailed shading analysis, battery storage sizing |
9. Harmonized System code block
| HS / HTS code | Description | How to look up US import duty |
|---|---|---|
| 8541.43 | Photovoltaic cells, assembled in modules or made up into panels | Look up General, Special, and Column 2 rates at USITC HTS — heading 8541.43. Verify any Section 201 / 232 / 301 measures at the time of importation. |
| 8541.40 | Photovoltaic cells, not assembled in modules or made up into panels | Look up at USITC HTS — heading 8541.40. |
| 8504.40 | Static converters (inverters for PV) | Look up at USITC HTS — heading 8504.40. |
| 8537.10 | Boards, panels, consoles for electric control/distribution | Look up at USITC HTS — heading 8537.10. |
For EU imports, look up the CN heading and any measures at EU TARIC consultation. For UK imports, use UK Global Tariff lookup. Duty rates are not asserted as facts in this document; verify at the time of importation and account for any Section 201, 232, 301, EU CBAM, anti-dumping or safeguard measures.
10. Provenance and audit trail
- JinkoSolar Tiger Neo 3.0 flyer (PDF) — module family and STC output range.
- JinkoSolar Tiger Neo 3.0 product page — module family landing.
- Sungrow SG125HV product page — reference inverter family.
- Sungrow string-inverter range page — reference inverter family.
- K2 Systems CrossRail System (US) — mounting reference.
- NREL PVWatts — reference for US-average specific annual yield band.
- EC JRC PVGIS — site-specific yield lookup.
- NREL/TP-7A40-87810 — U.S. Solar PV and Storage Cost Benchmarks — capex per Wp.
- NREL/TP-7A40-80686 — PV O&M Costs.
- EIA Electric Power Monthly, Table 5.6.A — retail band applied as this model's avoided-cost rate.
- EIA Annual Energy Outlook 2024 — electricity price CAGR band.
- NREL/TP-5J00-72155 — PV degradation meta-analysis (Jordan & Kurtz).
- Ofgem retail-market indicators — UK retail tariff series for cross-check.
- UL solar PV certification services.
- UL 61730-1 product page.
- IEC 61215-1:2021 ed2 (TC 82).
- IEC 61215-1-1:2021 (TC 82).
- IEC 62109-1:2010 (TC 82).
- IEC 62109-2:2011 (TC 82).
- USITC Harmonized Tariff Schedule — HS / HTS classification lookup.
- EU TARIC consultation — CN duty and measures lookup.
- UK Global Tariff lookup.
Internal assumptions (not source-asserted; bounded defaults from the model): discount rate 7 %, project horizon 25 yr, self-consumption 100 %, export tariff 0 (ZERO-AS-MISSING), residual value 0 at year 25, no inverter replacement in horizon, effective avoided-cost rate USD 0.14/kWh. Override all of the above with project-specific computed values before procurement.