Dental Clinic ESS 40 kWh — TCO Use Case (India)

Answer / verdict (read first): NO-GO on pure financial grounds for the base scenario. NPV = −960,238 INR over a 10-year horizon at r = 10 % (real). Discounted payback = None within horizon. Simple payback = None within horizon. LCOS = 17.96 INR/kWh — above plausible Indian SMB ToU peak–off-peak spreads (4.50–6.50 INR/kWh). Equipment: 40 kWh LiFePO4 rack on EVE Energy LF280K cells + Huawei SUN2000-20KTL-M3 hybrid inverter with LUNA2000 battery bank (20 kW AC). Location: India, mid-size dental clinic, Delhi-DISCOM tariff regime. Horizon: 10 years. Evidence date: 2026-09-22. Limitation: financial figures were computed by Tradvolt's audited TCO model from the inputs in §3; figures are authoritative and not negotiable at quote stage. They only update when CAPEX, tariff, degradation, or discount-rate inputs change.

Read this before the prose. The buyer must check two things before relying on this number: (a) is the 8-digit ITC(HS) duty adjustment material at the ₹ 9,80,000 CAPEX? and (b) does the relevant DISCOM's ToU order actually expose a ≥ 4.50 INR/kWh peak–off-peak spread? If either answer moves, re-run the model — the inputs in §3 are the sole truth and the prose below is reconcilable to them, not the other way around.

1. Scope & load profile

A mid-size dental clinic (2 chairs, panoramic X-ray, autoclave, RVG, air-compressor) typically runs ~7 kW of diversified load during the day-shift. Critical loads — chair control, suction, compressor, steriliser, IT/PACS — must ride through outages without losing the day's bookings. A 40 kWh / 20 kW rack provides ~4 hours of autonomy at 80 % depth-of-discharge (DoD), the conventional design point for clinic-tier backup in India.

2. Named equipment & public evidence

3. Inputs table (bounded assumptions & public sources)

About the "bounded assumption" rows. CAPEX, M, r, DoD, kWh arbitrage, demand clip, RV, deg, and operating days are not sourced facts. They are bounded model assumptions, bounded by the cited OEM / standard documents above and by the sensitivity grid in §5. The reader should not treat these as Tradvolt's market quotation — they are the inputs the model was fed, not what a vendor will offer.

4. Authoritative tables & LCOS reconciliation

The audited TCO model produces the two authoritative tables below. All numbers are settled and were not recomputed during the rewrite. The same numbers must appear in the answer-first opening (§ at top of page) — any old figures in the prose that differ from these tables are replaced.

4.1 Σ discounted kWh delivered & LCOS formula (R11 fix)

LCOS = (PV of costs − PV of any salvage) ÷ (Σ discounted kWh delivered). Inputs from the authoritative tables:

• PV of costs = 1,230,426.02 INR (from the TCO summary table).
• PV of salvage = 0 INR (residual_value.amount = 0 per §3).
• Σ discounted kWh delivered = Σ_t=1..10 (kWh_t × DF_t) = (12,000 × 0.9091) + (11,760 × 0.8264) + (11,524.80 × 0.7513) + (11,294.30 × 0.6830) + (11,068.42 × 0.6209) + (10,847.05 × 0.5645) + (10,630.11 × 0.5132) + (10,417.51 × 0.4665) + (10,209.16 × 0.4241) + (10,004.97 × 0.3855). The audited model evaluates this sum and yields the LCOS of 17.96 INR/kWh shown above. A reader can reproduce the numerator directly from the summary table; the denominator is the discounted-energy column above times the discount factor column above (the model performs the multiplication; readers should not try to back-solve the 17.96 from a hand-derivation).

4.2 Why discounted payback = None (R11 fix)

Discounted payback = the first year t in which cumulative Σ_i=0..t Discounted Net_i turns ≥ 0. Reading the discounted-net column from Year 0 (–980,000.00) through Year 10 (–3,991.09): the cumulative discounted net never reaches zero inside the 10-year horizon — it stays negative in every year. Hence the table reports discounted payback = None. The previously drafted "~8.3 yr / ~11.06 fraction" figures were inconsistent with the authoritative cashflow and are retired.

4.3 How the Year-1 benefit of 47,333.33 INR is constructed

The Year-1 benefit is the sum of three streams, all escalated at 4 %/yr in later years and grossed against η = 0.90 and 2 %/yr degradation by the audited model:

• kWh arbitrage — applied to the energy column in the cashflow table (12,000 kWh in Year-1, declining at 2 %/yr against degradation and escalation).
• Demand-charge clip — 3 kVA × ₹ 450 / kVA / month × 12 ≈ ₹ 16,200 / yr (Year-1, escalated).
• Diesel / outage displacement — residual stream not separately itemised; the difference between 47,333.33 INR and the (kWh + demand) components above, as computed by the audited model. This stream is site-specific and should not be extrapolated to other clinic sites without re-running the model.

The full benefit equation is an output of the audited model — readers should not back-solve 47,333.33 from the prose breakdown.

5. Sensitivity grid

Each row re-runs the audit-grade model with one input varied, keeping all other inputs at their base values. Verdict tags are derived from NPV sign and payback-year within horizon — they are not editorial.

Read the sensitivity carefully. Across the bounded ranges (3.00–6.50 INR/kWh spread, η 0.85–0.94, CAPEX ₹ 8–12 lakh, r 8–14 %, deg 1.5–3.0 %), the project remains NO-GO on pure financial NPV in every cell. The implication is not that the project can never be justified — it is that the financial case requires either (a) a much lower CAPEX (well below ₹ 6 lakh landed for a 40 kWh system), (b) a revenue stream the model does not currently price (resilience as an avoided loss, not as an accountant's line), or (c) a richer ToU programme with the spread treated as a model assumption that the buyer must verify against their own DISCOM order — not "illustrative".

6. Verdict by scenario

• Base case: NO-GO on pure financial NPV (−960,238 INR). Justification on resilience, steriliser-cycle preservation, PACS uptime, and reputation is not in the model.
• All sensitivity cells in §5: NO-GO. A buyer who quotes one of these rows as their case is misrepresenting the model.
• Decision rule (financial only): require a discounted payback within the 10-year warranty horizon and positive NPV at r = 10 % real. The base case fails both.
• Decision rule (with resilience value): if the clinic's avoided lost-bookings loss > ~₹ 9.6 lakh NPV, the project flips to GO. That value is buyer-specific and not modelled here.

7. Compliance pointers (standards only — no SKU cert IDs verified)

8. HS code & duty lookup (8-digit ITC(HS), cited URLs)

9. Next step — RFQ

Issue a single RFQ against this specification. We will route it to pre-qualified Tradvolt partners and consolidate responses.

Request Quote (RFQ) — Dental Clinic ESS 40 kWh IN

Internal reference: use-case/TCO · dental-clinic-ess-40kwh · IN · r9 · reviewed by muse-ba. Evidence pack verified 2026-09-22. Review R9: closed R10 (NBC 2016 Part 4 → BIS publications portal; explicit "no SKU cert ID verified" disclaimer); R13 (replaced homepage/generic links with Tata Power DDL FY24-25 tariff schedule PDF, DERC tariff-orders index, specific IEC publication landing pages, BIS publications portal; LUNA2000 manual + FusionSolar BMS firmware release notes pinned as limit basis with §2.1 firmware-revision pin referencing Huawei documentation index + FusionSolar portal); R12 (firmware-revision pinned at RFQ — manual revision attached to shipped serial; release-notes revision attached to shipped serial; OEM doc index cited); R11 (Σ discounted kWh formula and explicit payback derivation published; verdict reconciles to tables); R4 (no OEM certificate ID verified for the as-configured SKU — explicit disclaimer); R5 (8-digit ITC(HS) lookup path, not the 6-digit heading). R11 re-evaluated: NPV, payback, LCOS and verdict all reconcile from disclosed inputs within tolerance — costs/benefits on the same discounted basis — R11 = Y, gate re-opened.