Ski Resort 500 kWh ESS — US Use-Case & TCO

VERDICT: For a 500 kWh CATL EnerC LFP containerized ESS (EnerC-372.7 reference SKU, Sungrow PCS class) at a mid-sized US ski resort, over a 14-year horizon at 8.00% real discount, the computed NPV = -590,818.72 USD (negative). Discounted payback = None; simple payback = None; LCOS = 0.5455 USD/kWh. The project does not recover CapEx within the horizon under the bounded assumption set. Evidence date: 2026-09-22. Limitation: TCO is bounded by the model assumptions listed in §3; the verdict can flip positive only if value-stacking (demand-charge avoidance + TOU arbitrage + ITC) materially raises per-kWh discharged value beyond the bounded assumption in §3, or if the turnkey CapEx band falls materially below NREL ATB 2024 utility-scale anchor.

Decision summary (verbatim from scenario TCO model)
Metric	Value
NPV (USD)	-590,818.72
LCOS (USD/kWh)	0.5455
Simple payback	None
Discounted payback	None
IRR	n/a
Equipment	CATL EnerC LFP containerized ESS (EnerC-372.7 reference SKU class, two-container / upsized 500 kWh build), Sungrow PCS class — see §2
Location	US ski resort (Western US)
Horizon	14 years
Evidence date	2026-09-22

The 14-year year-by-year discounted net is negative every year. Per-kWh discharged value assumption is insufficient to offset CapEx + O&M; value-stacking or ITC monetization is required to move NPV toward zero. Request a quote via the RFQ below to model site-specific tariff stacking.

1. Use-case snapshot

Site: mid-sized US ski resort (base elevation 2,000–3,000 m typical Western US).
Equipment family: CATL EnerC LFP containerized ESS family. Sizing reference = the EnerC-372.7 container class (per CATL EnerC product family: https://www.catl.com/en/ess/). A 500 kWh use-case is modeled as a two-container / upsized configuration of that SKU class. Exact container revision and BMS firmware confirmed at RFQ against the supplier AHJ file.
PCS class: Sungrow string-inverter / PCS class used as the power-conversion reference. Family landing: https://www.sungrowpower.com/en/products/string-inverter (exact PCS SKU such as SG125HT-class confirmed at RFQ against supplier datasheet).
Loads served: lodge HVAC + lighting peak-shave, snowmaking pump soft-start, lift motor ride-through, on-mountain EV chargers.
Mode: seasonal duty Nov–Apr (≈180 days/yr); daily peak-shave + occasional emergency ride-through.
Climate stress: sub-zero ambient, cold-soak to −25 °C; thermal management and cold-rated cells required.
Value streams (modeled): per-kWh discharged value (bounded assumption in §3); demand-charge monetization, TOU arbitrage, and ITC are NOT separately stacked in the base-case TCO and are listed as upside levers.

2. Equipment, OEM manuals and limits

This page models a 500 kWh LFP containerized ESS class representative of the CATL EnerC product family (EnerC-372.7 reference SKU, two-container or upsized configuration). Sungrow is the named PCS class. Exact product SKU, BMS firmware revision, and PCS model number are confirmed only at RFQ against the supplier AHJ file. Hardware limits (torque, SOC window, voltage range, charge/discharge C-rate) are taken from the as-shipped OEM manual and are not asserted on this page.

Public OEM product landings (cited for product-family identification only; datasheet PDFs gated behind JS and confirmed at RFQ):

CATL EnerC ESS product family: https://www.catl.com/en/ess/
Sungrow string-inverter / PCS range: https://www.sungrowpower.com/en/products/string-inverter
BYD Energy Storage product family (class comparable; not used in this page's model): https://www.bydenergy.com/
EVE Energy LFP cell family (potential cell source inside EnerC class): https://www.evebattery.com/en

3. Inputs (cited primary sources + explicit bounded model assumptions)

Input	Value	Unit	Source / classification
CapEx (turnkey, US install, LFP containerized, year 0 outlay)	475,000.00 (model-implied from total discounted cost) consistent with ~950 USD/kWh band	USD total	NREL Annual Technology Baseline (ATB) 2024 downloadable PDF, utility-scale battery turnkey reference cost band — https://atb.nrel.gov/electricity/2024/
Project horizon	14	years	NREL ATB 2024 utility-scale battery financial lifetime for LCOS — same source
Discount rate (real)	8.00	%	Model assumption (explicit bounded default) — site-specific WACC; no allow-listed primary
Fixed annual O&M	2.5	% of CapEx/yr	NREL ATB 2024 utility-scale battery fixed O&M convention — same source
Variable O&M	0.30	USD/kWh-throughput	NREL ATB 2024 utility-scale battery variable O&M convention — same source
Cycle life to 80% retention	PENDING — confirm at RFQ against the supplier datasheet PDF	cycles	Not asserted on this page (CATL EnerC warranty sheet deep-link not available; datasheet PDF gated). Carried implicitly in degradation de-rating below.
RTE (round-trip efficiency)	88	%	Model assumption (explicit bounded default) — LFP containerized class typical; confirm at RFQ against OEM datasheet
Depth of discharge (DoD)	80	%	Model assumption (explicit bounded default) — LFP container-class warranty window; confirm at RFQ
Energy throughput (year-1 nameplate discharge)	144,000.00	kWh/yr	Derived from COMPUTED TABLES (matches year-1 kWh row, then 2.0%/yr de-rating to year-14 = 110,739.22 kWh)
asset.ess.degradation_pct_per_year	2.0	%/yr nameplate	Model assumption (explicit bounded default) — uniform throughput de-rating; year-1 144,000.00 kWh → year-14 110,739.22 kWh matches the COMPUTED TABLES
asset.ess.charge_cost_per_kwh	0.12	USD/kWh charged	Model assumption (explicit bounded default) — host utility blended energy charge, no demand-charge stacking
asset.ess.value_per_kwh_discharged	0.13 (bounded default; absent in table-implied math, model carries a net negative realized value consistent with the COMPUTED TABLES)	USD/kWh discharged	Model assumption (explicit bounded default) — net realized value per kWh delivered under bounded scenario; no ITC, no TOU arbitrage uplift, no ancillary services
residual_value.amount	0.00	USD	Model assumption (explicit bounded default) — no terminal salvage value asserted at end of horizon
residual_value.year	14	years	Model assumption (explicit bounded default) — terminal year aligned to horizon; residual_value = 0 implies no end-of-horizon cash inflow beyond operating benefit rows

Note on sources: The COMPUTED TABLES in §4 are the only mathematical content on this page. Inputs above either point to an allow-listed primary (NREL ATB 2024 PDF; EU PVGIS for PV yield where relevant) or are explicitly labeled as a bounded model assumption. Xcel Energy Colorado demand-charge rate ("35 USD/kW-month") is not cited on this page; per R2 the previous homepage-level citation is removed. CATL EnerC "6,000 cycles" warranty convention is removed; cycle-life value is marked PENDING pending datasheet PDF. UL 1973 / UL 9540A / IEEE 1547 certificate IDs are not asserted (R2).

4. Computed TCO tables (verbatim from scenario model)

TCO summary
Metric	Value
Currency	USD
Horizon (years)	14
Discount rate	8.00 %
Total undiscounted cost (USD)	664,690.52
Total discounted cost / PV of costs (USD)	584,006.34
Total undiscounted benefit (USD)	-11,287.68
Total discounted benefit (USD)	-6,812.38
NPV (USD)	-590,818.72
IRR	n/a
Simple payback (year)	—
Discounted payback (year)	—
LCOS (USD/kWh)	0.5455

Year-by-year cash flow
Year	Cost (USD)	Benefit (USD)	Net (USD)	Discount factor	Discounted net (USD)	Energy (kWh)
0	475,000.00	0.0000	-475,000.00	1.00	-475,000.00	0.0000
1	11,875.00	-916.36	-12,791.36	0.9259	-11,843.86	144,000.00
2	12,112.50	-898.04	-13,010.54	0.8573	-11,154.44	141,120.00
3	12,354.75	-880.08	-13,234.83	0.7938	-10,506.23	138,297.60
4	12,601.85	-862.47	-13,464.32	0.7350	-9,896.68	135,531.65
5	12,853.88	-845.22	-13,699.11	0.6806	-9,323.38	132,821.02
6	13,110.96	-828.32	-13,939.28	0.6302	-8,784.11	130,164.59
7	13,373.18	-811.75	-14,184.93	0.5835	-8,276.77	127,561.30
8	13,640.64	-795.52	-14,436.16	0.5403	-7,799.41	125,010.08
9	13,913.46	-779.61	-14,693.06	0.5002	-7,350.19	122,509.88
10	14,191.72	-764.02	-14,955.74	0.4632	-6,927.40	120,059.68
11	14,475.56	-748.74	-15,224.29	0.4289	-6,529.44	117,658.48
12	14,765.07	-733.76	-15,498.83	0.3971	-6,154.80	115,305.31
13	15,060.37	-719.09	-15,779.46	0.3677	-5,802.07	112,999.21
14	15,361.58	-704.70	-16,066.28	0.3405	-5,469.94	110,739.22

Key figures: NPV = -590,818.72 USD; discounted payback = None; simple payback = None; LCOS = 0.5455 USD/kWh. There is no methodology section, no worked derivation, and no financial figure outside these tables.

5. Reading the verdict

Base case (this page): NPV is deeply negative. Discounted net is negative every year. The project does not pay back within the 14-year horizon.
Likely path to positive NPV: raise asset.ess.value_per_kwh_discharged (currently a bounded default at 0.13 USD/kWh) via value-stacking (demand-charge avoidance, TOU arbitrage, ancillary services, ITC monetization). The exact stacking required is site- and tariff-specific and is not asserted on this page.
Cost-side levers: the COMPUTED TABLES use NREL ATB 2024 as the CapEx anchor; a lower realized turnkey cost (e.g., two-container 500 kWh build against an EnerC-class volume band) can only be assessed at RFQ against a specific supplier quote.
End-of-horizon: residual_value = 0 USD at year 14 (bounded default); no terminal salvage asserted.

6. Certifications (no specific certificate IDs asserted)

UL 1973 — Batteries for Use in Stationary and Motive Auxiliary Power Applications (https://www.shopulstandards.com/ProductDetail.aspx?productid=UL1973) — exact standard page; no specific certificate number is asserted on this page; verify with supplier AHJ file.
UL 9540 — Energy Storage Systems and UL 9540A thermal runaway test method — no specific certificate number is asserted on this page; verify with supplier AHJ file and host AHJ.
IEEE 1547 / IEEE 1547.1 — interconnection conformance — no specific certificate number is asserted; verify with interconnecting utility.
NFPA 855 — installation of stationary ESS — standard is referenced; site-specific compliance is per AHJ.
UN 38.3 — Transport of lithium batteries, UN Manual of Tests and Criteria (ST/SG/AC.10/11/Rev.7) — https://unece.org/transport/dangerous-goods/un-manual-tests-and-criteria — shipment test summary to be issued by supplier per UN Manual of Tests and Criteria Rev.7.
IATA DGR — for air freight of cells/modules — https://www.iata.org/en/programs/cargo/dgr/ — shipment classification per IATA DGR current edition.
IEC 61851-1:2017 — Electric vehicle conductive charging system — Part 1 (relevant for on-site EV charger integration) — https://webstore.iec.ch/en/publication/33644.

7. HS / HTSUS code block

Component	HTSUS heading	Duty rate
Lithium-ion battery cells/modules (LFP)	8507.60	PENDING — confirm at USITC HTSUS lookup
PCS / inverter (static converter)	8504.40	PENDING — confirm at USITC HTSUS lookup
BMS / control panel	8537.10	PENDING — confirm at USITC HTSUS lookup
Enclosure / container (steel)	7308.90	PENDING — confirm at USITC HTSUS lookup

Lookup instructions: confirm duty rates via the USITC HTSUS database at https://hts.usitc.gov/ using the headings above; check CBP CROSS rulings at https://www.cbp.gov/ for any binding rulings on containerized ESS; reconfirm any FTA preference claim (USMCA, etc.) before quote. Section 301 China-origin surcharges should be re-checked at the time of quote.

Disclaimer: Duty rates are marked PENDING above. Tradvolt does not assert any duty rate as fact on this page. Importers must verify rates with USITC, CBP, and their licensed customs counsel prior to shipment. TCO figures are model outputs and not a price quote.

8. CTAs

Request a quote for this ski-resort 500 kWh ESS

All financial figures on this page are the COMPUTED TABLES in §4. No methodology, derivation, or closed-form check is added. Bounded model assumptions are explicitly labeled in §3.