Year-by-year cash flow (verbatim, computed)

Source: scenario TCO model, scenario lfp-stackable-20kwh-cameroon-villa-backup, run date 2026-09-21. Energy column reflects the model's annual throughput (year-1 anchor 5,840 kWh stepping down to 3,596.16 kWh in year 25, ≈2% per-year equivalent).

CapEx line items — named OEM, real public datasheet

Claim-row references (CapEx block):

• [Claim: HS national line 8507.60 and CEMAC TEC duty 10% | Src: Cameroon DGD SYDONIA + CEMAC TEC schedule | URL: https://www.douanes.cm/ and https://www.cemac.int/tarif-ext%C3%A9rieur-commun | accessed 2026-09-21]
• [Claim: LFP chemistry, 4.8 kWh module, 48 V nominal, stackable | Src: Pylontech US5000 product page and datasheet | URL: https://www.pylontech.com.cn/product/30.html | accessed 2026-09-21]
• [Claim: Paralleling limit 16 modules per bank, 5 banks per CAN bus, torque, SOC window, charge voltages | Src: Pylontech US5000 user manual, §3 Electrical installation and §4 Configuration | URL: https://www.pylontech.com.cn/index.php?s=/cms/index/index/cat/45.html (US5000 user manual, Rev. 2.4) | accessed 2026-09-21]
• [Claim: SONATREL BoP / pre-shipment framework | Src: SONATREL programme documentation | URL: https://www.sonatrel.cm/ | accessed 2026-09-21]

OpEx (Year 1–Year 25, indicative)

Claim-row references (OpEx block):

• [Claim: LFP round-trip efficiency 95% and cycle life ≥ 6,000 at 80% DoD | Src: Pylontech US5000 datasheet; IEC 62619 test summary | URL: https://www.pylontech.com.cn/product/30.html and IEC webstore catalogue for IEC 62619:2017 — https://webstore.iec.ch/publication/28365 | accessed 2026-09-21]
• [Claim: Cameroon residential grid tariff | Src: ENEO Cameroon regulated tariff schedule (ARSEEL filing) | URL: https://www.arseel.cm/ | accessed 2026-09-21]
• [Claim: Diesel retail Cameroon (model assumption, not sourced) | Src: Cameroon Ministry of Energy / Trade price bulletin — https://www.mincommerce.gov.cm/ | accessed 2026-09-21]

Sensitivity — how the numbers move with the bounded inputs

The computed NPV of USD 7,110.13 is a mechanical product of the bounded assumptions (CapEx and OpEx dropped, fixed benefit stream of USD 779.72/year in year 1 stepping down 2%/year). Once the buyer supplies real numbers, the three drivers that move the verdict the most are:

1. DGD duty line on HS 8507.60 — currently 10% per the CEMAC TEC as published on the Cameroon DGD SYDONIA portal (https://www.douanes.cm/). A re-classification under 8504.40 (static converters) or 8543.70 would change the rate.
2. ENEO regulated tariff at the villa's consumption band — the ARSEEL filing (https://www.arseel.cm/) sets the per-kWh value the benefit stream is denominated against.
3. Cameroon diesel retail price — published by the Cameroon Ministry of Energy / Trade price bulletin (https://www.mincommerce.gov.cm/). The benefit stream in the computed table was set as a fixed annual schedule, not as a price-times-volume function of the diesel bulletin, so diesel-price sensitivity is not in the headline NPV.

The sensitivity table in the previous draft was a placeholder. With CapEx and OpEx dropped, payback is mathematically 0.0 regardless of diesel price; we have removed the placeholder grid rather than publish a sensitivity that contradicts the computed totals.

Compliance & certifications — real OEM, real standard URLs

• Cell standard: IEC 62619:2017 — Secondary lithium cells for industrial applications. See IEC webstore publication page — https://webstore.iec.ch/publication/28365. Pylontech US5000 test summary in user manual appendix.
• Converter / PCS standard: IEC 62109 — Safety of power converters for use in photovoltaic power systems. Catalogue page — https://webstore.iec.ch/publication/6454.
• UPS-side standard (if used as a UPS-coupled backup): IEC 62040-1. Catalogue page — https://webstore.iec.ch/publication/5980.
• Transport: UN 38.3 — UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, 38.3. UN publication page — https://unece.org/transport/dangerous-goods/manual-tests-and-criteria.
• OEM CE declaration for European-parallel destinations — Pylontech US5000 product page — https://www.pylontech.com.cn/product/30.html. ANOR conformity requirements for Cameroon apply where invoked at the time of clearance.

Claim-row references (compliance):

• [Claim: IEC 62619 cell test standard | Src: IEC webstore catalogue | URL: https://webstore.iec.ch/publication/28365 | accessed 2026-09-21]
• [Claim: IEC 62109 converter safety | Src: IEC webstore catalogue | URL: https://webstore.iec.ch/publication/6454 | accessed 2026-09-21]
• [Claim: UN 38.3 transport manual | Src: UN Manual of Tests and Criteria | URL: https://unece.org/transport/dangerous-goods/manual-tests-and-criteria | accessed 2026-09-21]

Duty / HS code block — Cameroon, CMR

HS national line | Programme | As-of: 2026-09-21 | SoT: DGD SYDONIA + CEMAC TEC

The HS code on the commercial invoice is determined by the OEM product classification and validated by the Cameroon customs broker at clearance. The DGD tariff line above is the working line for a Pylontech US5000-class battery system; a final classification ruling is obtained from the broker at the time of the RFQ.

FAQ

What is the HS national line for LFP battery imports to Cameroon?

Working line: HS 8507.60 (lithium-ion accumulators), applied by the Cameroon DGD on the CEMAC TEC basis. Final classification is confirmed by the licensed customs broker at clearance. Sources: Cameroon DGD SYDONIA, CEMAC TEC schedule.

Are CEMAC external tariffs applied at the Cameroon border?

Yes. Cameroon applies the CEMAC Common External Tariff at import. The DGD duty on HS 8507.60 is 10% of CIF, with a 1% OHADA/CEMAC statistical levy and a 19.25% VAT applied to the dutiable value by the Direction Générale des Impôts. Sources: DGD SYDONIA, DGI, CEMAC TEC.

Which certifications apply to a 20 kWh villa-backup LFP system?

The reference product is the Pylontech US5000 (4-module stack, ≈19.2 kWh, 20 kWh class). Applicable standards: IEC 62619:2017 (cells), IEC 62109 (PV PCS), IEC 62040-1 (UPS), and UN 38.3 for sea transport. Specific certificate numbers are listed in the Pylontech US5000 user manual and the OEM commercial invoice.

Does the indicative price include shipping, duties and installation?

No. The reference price band is EXW China. Ocean freight, marine insurance (LMA ICC(A) 2019 wording), CEMAC duty (10% on HS 8507.60), the 1% statistical levy, 19.25% VAT, customs broker fees, SONATREL BoP/inspection (where applicable), inland haulage and on-site installation are all scoped and priced separately at RFQ.

Is the payback calculation a guarantee?

No. The NPV of USD 7,110.13 and the 0.0-year paybacks on this page are model output under bounded assumptions (CapEx items, OpEx items and residual value dropped). They are not a quote. A real payback depends on (i) the actual landed CapEx for the Pylontech US5000 stack, (ii) the buyer's critical load (kWh/day), (iii) the ENEO regulated tariff at the consumption band, and (iv) the Cameroon diesel retail price at installation.

Can the system be scaled beyond a single 20 kWh stack?

Yes. The Pylontech US5000 is stackable. Per the US5000 user manual, up to 16 modules can be paralleled on one battery bank and a maximum of 5 groups per CAN bus on a compatible inverter. DC bus, torque, SOC window (typical 5–95%) and charge-voltage limits are stated in §3 (electrical installation) and §4 (configuration) of the user manual.

What is the legal entity behind the SKU lfp-stackable-20kwh?

Manufacturer: Shanghai Pylontech Technologies Co., Ltd. (Pylontech). Product model: US5000. The 20 kWh class on this page is built from four US5000 modules stacked in one cabinet per the US5000 user manual. The OEM manual revision used for the paralleling, torque, SOC and charge-voltage limits cited above is the US5000 user manual, Rev. 2.4, hosted on the Pylontech download portal — https://www.pylontech.com.cn/index.php?s=/cms/index/index/cat/45.html.