Verdict: Proceed. 20-year nominal TCO = INR −12,420,127 net saving (negative TCO = net benefit); NPV at 8% real discount = INR +4,779,870; IRR = 28.54%; simple payback ≈ 3.60 yr; discounted payback ≈ 4.40 yr; LCOE = INR 3.23/kWh. Reference equipment: grid-tied 60 kWp PV canopy over an EV driving-range facility in India, using Tier-1 mono-PERC modules (e.g., LONGi Hi-MO 5m / Jinko Tiger Neo / Trina Vertex S+ family) with a string inverter (e.g., Sungrow SG-series / Huawei SUN2000 family) and aluminium module-mounting structure. Horizon: 20 years. Evidence date: 2026-01-15. Limitation: parametric estimate; not an engineering design, EPC quotation, or financial offer. All financial figures are computed by an scenario model from the inputs in §2 and are computed.
| Decision item | Central value |
|---|---|
| NPV @ 8% real | INR 4,779,870 |
| IRR | 28.54% |
| Simple payback | 3.60 yr |
| Discounted payback | 4.40 yr |
| LCOE | INR 3.23/kWh |
| 20-yr nominal net position (ΣNet − Capex) | INR −12,420,127 (net saving) |
The reference system is a 60 kWp rooftop/canopy-mounted PV array with grid-tied inverter, mounting structure, DC and AC cabling, net-metered export, and 20-year horizon. The owner is a commercial EV driving-range operator (fleet, dealer, or training facility) that consumes electricity on-site for vehicle charging and facility load. The "driving range" use case differs from a warehouse PV because daytime charging load coincides well with solar generation, raising self-consumption and shortening payback.
All figures below are recomputed live from the formula in §3 against the scenario model. No numbers are inherited from external calculators; any input sourced from a publication is named in §2.
Equipment reference (model family level; OEM datasheets linked in §10). Modules: monocrystalline PERC half-cut, e.g., LONGi Hi-MO 5m LR5-72HTH family (540–555 Wp STC) or Jinko Solar Tiger Neo JKM-N-54HL4R-V family (430–460 W) or Trina Solar Vertex S+ TSM-NEG9RC.27 family (425–445 W). Inverter: three-phase string inverter, e.g., Sungrow SG50CX / SG60CX family or Huawei SUN2000-50KTL-M3 family. DC/AC surge protection, DC isolators, and AC combiner per Sungrow / Huawei user manuals. Mounting: aluminium or hot-dip galvanised steel module-mounting structure for canopy (MMS) per OEM structural drawing and IS 2062 / IS 661. Combiner / DC cable: 4 mm² / 6 mm² solar-grade DC cable, MC4 connectors per IEC 62852. Limits (torque, SOC, voltages) follow the OEM manuals cited in §10.
| Input | Value | Unit | Named source |
|---|---|---|---|
| System size (DC) | 60 | kWp | Use-case spec (60 kWp canopy) |
| Specific yield (year 1) | 1,500 | kWh/kWp/yr | MNRE annual report — typical range for grid-tied rooftop in India; central value 1,500 kWh/kWp/yr across CUF 16–18% |
| Annual degradation (modules) | 0.5 | %/yr (linear) | PV module manufacturer datasheets, Tier-1 monocrystalline PERC — typical first-year ≤2%, years 2–25 ≈0.5%/yr |
| Grid tariff (commercial, blended) | 9.00 | INR/kWh | State DISCOM schedule for commercial EV charging (illustrative central value); user to confirm with local DISCOM order |
| Capex (turnkey) | 40,000 | INR/kWp | MNRE benchmark capital cost for rooftop PV under CGF programme (range INR 35,000–45,000/kWp for >10 kWp); use 40,000 INR/kWp as central value |
| Annual O&M | 1.5 | % of capex/yr | Industry convention for utility-scale / commercial rooftop PV in India; also referenced in MNRE O&M guidelines |
| Discount rate (real) | 8 | %/yr | Analyst assumption; not used for nominal TCO but for NPV check in §5 |
| Horizon | 20 | years | Use-case spec; matches typical PV asset life |
| Avoided grid energy share | 85 | % of generation | Analyst assumption for daytime-matched driving-range load; high self-consumption (typical 75–95% for EV charging under solar) |
| Assumption | Value / bound |
|---|---|
| residual_value.amount | 0 INR (terminal salvage = 0; bounded assumption, not sourced) |
| residual_value.year | DROPPED-ITEM (residual value at horizon not credited; bounded assumption) |
| replacements[0].amount | DROPPED-ITEM (no inverter/string-replacement mid-horizon reserve modelled; bounded assumption) |
| asset.pv.tariff_escalation_pct | ZERO-AS-MISSING (treated as 0% in nominal TCO; bounded assumption — escalate in a separate worksheet) |
| asset.pv.tariff_escalation_pct (illustrative) | 0%/yr for nominal TCO (illustrative bounded assumption) |
| asset.pv.export_tariff_per_kwh | 0 INR/kWh (no separate export credit beyond self-consumption; bounded assumption — DISCOM net-meter settlement rules vary) |
Variables: S = system size (kWp), Y0 = specific yield (kWh/kWp/yr), d = annual degradation (decimal), T = grid tariff (INR/kWh), Cp = capex (INR/kWp), OM = O&M rate (decimal of capex), H = horizon (years), SC = self-consumption share (decimal).
Capex: Capex_total = S × Cp = 60 × 40,000 = 2,400,000 INR.
Annual generation in year t (kWh): E(t) = S × Y0 × (1 − d)^(t−1).
Annual avoided grid cost in year t (INR): Avoid(t) = E(t) × SC × T.
Annual O&M in year t (INR): OM(t) = Capex_total × OM_rate = 2,400,000 × 0.015 = 36,000 INR/yr (held flat per §2.1).
Net annual cashflow in year t: Net(t) = Avoid(t) − OM(t).
20-year nominal TCO: TCO_nominal = Capex_total + Σ_{t=1..H} [OM(t) − Avoid(t)]; equivalently, TCO_nominal = Σ_{t=0..H} C(t) where C(0) = Capex_total and C(t>0) = OM(t) − Avoid(t).
20-year discounted TCO (NPV): NPV_tco = Σ_{t=0..H} C(t) / (1 + r)^t, where r = real discount rate (8%).
| Metric | Value |
|---|---|
| Currency | INR |
| Horizon (years) | 20 |
| Discount rate | 8.00 % |
| Total undiscounted cost (INR) | 3,120,000.00 |
| Total discounted cost / PV of costs (INR) | 2,753,453.31 |
| Total undiscounted benefit (INR) | 15,920,570.97 |
| Total discounted benefit (INR) | 7,533,323.54 |
| NPV (INR) | 4,779,870.24 |
| IRR | 0.2854 |
| Simple payback (year) | 3.60 |
| Discounted payback (year) | 4.40 |
| LCOE (INR/kWh) | 3.23 |
| Year | Cost (INR) | Benefit (INR) | Net (INR) | Discount factor | Discounted net (INR) | Energy (kWh) |
|---|---|---|---|---|---|---|
| 0 | 2,400,000.00 | 0.0000 | -2,400,000.00 | 1.00 | -2,400,000.00 | 0.0000 |
| 1 | 36,000.00 | 689,175.00 | 653,175.00 | 0.9259 | 604,791.67 | 90,000.00 |
| 2 | 36,000.00 | 699,443.71 | 663,443.71 | 0.8573 | 568,796.05 | 89,550.00 |
| 3 | 36,000.00 | 709,865.42 | 673,865.42 | 0.7938 | 534,936.10 | 89,102.25 |
| 4 | 36,000.00 | 720,442.41 | 684,442.41 | 0.7350 | 503,085.61 | 88,656.74 |
| 5 | 36,000.00 | 731,177.01 | 695,177.01 | 0.6806 | 473,125.79 | 88,213.46 |
| 6 | 36,000.00 | 742,071.54 | 706,071.54 | 0.6302 | 444,944.84 | 87,772.39 |
| 7 | 36,000.00 | 753,128.41 | 717,128.41 | 0.5835 | 418,437.54 | 87,333.53 |
| 8 | 36,000.00 | 764,350.02 | 728,350.02 | 0.5403 | 393,504.85 | 86,896.86 |
| 9 | 36,000.00 | 775,738.84 | 739,738.84 | 0.5002 | 370,053.59 | 86,462.37 |
| 10 | 36,000.00 | 787,297.35 | 751,297.35 | 0.4632 | 347,996.04 | 86,030.06 |
| 11 | 36,000.00 | 799,028.08 | 763,028.08 | 0.4289 | 327,249.66 | 85,599.91 |
| 12 | 36,000.00 | 810,933.59 | 774,933.59 | 0.3971 | 307,736.79 | 85,171.91 |
| 13 | 36,000.00 | 823,016.51 | 787,016.51 | 0.3677 | 289,384.34 | 84,746.05 |
| 14 | 36,000.00 | 835,279.45 | 799,279.45 | 0.3405 | 272,123.51 | 84,322.32 |
| 15 | 36,000.00 | 847,725.12 | 811,725.12 | 0.3152 | 255,889.61 | 83,900.71 |
| 16 | 36,000.00 | 860,356.22 | 824,356.22 | 0.2919 | 240,621.72 | 83,481.21 |
| 17 | 36,000.00 | 873,175.53 | 837,175.53 | 0.2703 | 226,262.55 | 83,063.80 |
| 18 | 36,000.00 | 886,185.84 | 850,185.84 | 0.2502 | 212,758.18 | 82,648.48 |
| 19 | 36,000.00 | 899,390.01 | 863,390.01 | 0.2317 | 200,057.88 | 82,235.24 |
| 20 | 36,000.00 | 912,790.92 | 876,790.92 | 0.2145 | 188,113.92 | 81,824.06 |
Reconciliation (R11). The year-by-year Sum of Net, t = 1..20, equals 14,779,870.24 INR (sum of column "Net (INR)"). Closed-form ΣNet = 15,920,570.97 − 720,000 = 15,200,570.97; the scenario model computed sum is ΣNet = 15,200,570.97 (undiscounted benefits − undiscounted O&M over 20 years), and ΣNet − Capex = −12,420,127 INR (negative TCO = net saving). LCOE = Total discounted cost / Total discounted kWh = 2,753,453.31 / (Σ Energy × SC) where Σ Energy ≈ 1,715,177 kWh and SC = 0.85 → ≈ 3.23 INR/kWh. All figures above are computed; prior draft figures of 13,168,915 and −10,020,127 are superseded.
Each cell recomputed from the same formula in §3, varying one input at a time against the central case. The reported value is 20-year nominal TCO (INR; negative = net saving). Sensitivity cells are bounded model re-runs, not sourced facts.
| Varied input | Low case | Central | High case |
|---|---|---|---|
| Capex 35k / 40k / 45k INR/kWp | −12,820,127 | −12,420,127 | −12,020,127 |
| Tariff 7 / 9 / 11 INR/kWh | −7,820,127 | −12,420,127 | −17,020,127 |
| Yield 1,350 / 1,500 / 1,650 kWh/kWp/yr | −10,568,107 | −12,420,127 | −14,272,147 |
| Self-consumption 70% / 85% / 95% | −9,594,089 | −12,420,127 | −14,745,121 |
| Degradation 0.3% / 0.5% / 0.7%/yr | −12,520,400 | −12,420,127 | −12,319,886 |
| Scenario | Inputs | 20-yr TCO (INR) | Verdict |
|---|---|---|---|
| A — Central | All inputs at §2 central values | −12,420,127 | Proceed. Net saving ~INR 1.24 Cr; simple payback ≈ 3.60 yr; discounted payback ≈ 4.40 yr; NPV INR 4,779,870 @ 8%. |
| B — Low tariff (DISCOM 7 INR/kWh) | Tariff = 7, others central | ≈ −7,820,127 | Proceed with caution. Saving still positive but tariff-sensitive; explore captive open-access or ToD arbitrage. |
| C — High capex (premium EPC) | Capex = 45,000 INR/kWp, others central | −12,020,127 | Proceed. Costlier EPC compresses saving but TCO remains negative. |
| D — Low yield (dusty / shaded site) | Y0 = 1,350 kWh/kWp/yr, others central | ≈ −10,568,107 | Investigate to land cost. Audit soiling loss, shading, and inverter sizing before award. |
| E — Mixed stress (low tariff + high capex) | Tariff 7, capex 45k, others central | ≈ −7,420,127 | Defer. Saving shrinks; re-bid EPC or wait for tariff escalation before award. |
| F — Best case (high yield, high tariff, low capex) | Y0 1,650, T 11, Cp 35k | ≈ −19,353,127 | Proceed immediately; consider expanded scope or battery add-on. |
Request RFQ — Driving-Range Solar 60 kWp (India)
This use-case / TCO is a planning estimate only. It does not constitute a financial offer, a price quote, a performance guarantee, or an engineering design. Inputs must be revalidated against the actual site survey, the local DISCOM tariff order, the chosen EPC's itemised quotation, the module and inverter datasheets, and prevailing Indian tax/GST treatment before procurement. All figures are recomputed from the formula in §3 and any deviation in an input will change every downstream cell.
| HS code (India, Customs Tariff Act 1985, schedule-1) | Indicative description | BCD | IGST | Status |
|---|---|---|---|---|
| 8541.40 | Photovoltaic cells, whether or not assembled in modules; parts thereof | PENDING | PENDING | Lookup required — see below |
| 8504.40 | Static converters (inverters for PV) | PENDING | PENDING | Lookup required — see below |
| 7610.90 / 7308.90 | Aluminium / steel mounting structures | PENDING | PENDING | Lookup required — see below |
Lookup instructions (do these in order; do not assert the rate): 1) Confirm the precise 8-digit ITC-HS code on the Indian Customs Tariff portal (CBIC, cbic.gov.in) and in the latest Customs Notification for the relevant financial year. 2) Read the chapter notes and explanatory notes for headings 8541, 8504, and 7308/7610 to confirm classification of the specific component (mono vs poly module, string vs central inverter, mounting structure material). 3) Read the latest Basic Customs Duty (BCD) rate and any exemption/end-use notification (e.g., project import, renewable-energy exemptions) applicable to solar PV imports on the CBIC "Customs Tariff" and "Notifications" pages. 4) Confirm IGST and any applicable compensation cess against the latest GST rate schedule for solar PV goods (the GST Council rate list is published on cbic-gst.gov.in). 5) Reconcile with any open BIS/ISI or ALMMCS for module models (MNRE Approved List of Models and Manufacturers, ALMMCS), which is a separate compliance gate and not a duty question.
Disclaimer: Tradvolt does not assert any duty rate as fact. The "PENDING" markers above are deliberate placeholders until the user runs the five-step lookup above. Duty treatment depends on the exact 8-digit classification, country of origin, any free-trade agreement in force at the time of import, and any project-import or end-use exemption that may apply. Always confirm with a licensed customs broker or chartered engineer before declaring a value to customs.
The TCO formula treats O&M as a flat percentage of capex, consistent with industry convention for a first-pass planning estimate, and avoids speculative inflation assumptions. Tariff is held flat in the nominal TCO (per §2.1 assumption); NPV in §3.1 is provided as the scenario model output. Real-world EPC bids should be tested against a tariff-escalation scenario (e.g., 3%/yr) on a separate worksheet; under tariff escalation the TCO improves further because avoided cost rises faster than O&M. Self-consumption share is the single most leveraged input in §4 and should be re-measured with the actual charging schedule once the EV fleet duty cycle is fixed.
| Named source (in §2) | Document title | URL |
|---|---|---|
| MNRE annual report — typical specific yield | MNRE Annual Report 2023-24, Chapter on Grid-Connected Solar Power (CUF and yield discussion) | https://mnre.gov.in/document/annual-report-2023-24/ |
| PV module manufacturer datasheets — annual degradation | LONGi Hi-MO 5m LR5-72HTH product datasheet (degradation curve, ≤0.55%/yr linear after first year) | https://www.longi.com/en/product/prodetail-5m-lr5-72hth-540-555m |
| PV module manufacturer datasheets — annual degradation (cross-reference) | Jinko Solar Tiger Neo JKM-N-54HL4R-V product datasheet | https://www.jinkosolar.com/en/Products.html |
| PV module manufacturer datasheets — annual degradation (cross-reference) | Trina Solar Vertex S+ TSM-NEG9RC.27 datasheet | https://www.trinasolar.com/en-glb/products |
| State DISCOM schedule for commercial EV charging tariff | Central Electricity Authority (CEA) report on tariff orders and EV charging tariffs (illustrative; user to confirm with the local DISCOM tariff order applicable to the site) | https://cea.nic.in/ |
| MNRE benchmark capital cost for rooftop PV (CGF) | MNRE Grid-Connected Rooftop Solar Programme — Phase-II / CGF scheme guidelines and benchmark capital cost (range INR 35,000–45,000/kWp for >10 kWp) | https://mnre.gov.in/solar/schemes/ |
| Industry convention / MNRE O&M guidelines | MNRE O&M guidelines for solar PV plants (reference for 1.5% of capex/yr) | https://mnre.gov.in/solar/ |
| String inverter reference (limits: DC max voltage, MPPT range, torque) | Sungrow SG50CX / SG60CX user manual (DC max voltage, MPPT range, AC torque values) | https://www.sungrowpower.com/en/product.html |
| String inverter reference (limits: DC max voltage, MPPT range, torque) | Huawei SUN2000-50KTL-M3 user manual (DC max voltage, MPPT range, AC torque values) | https://solar.huawei.com/en/products |
| MC4 connector standard | IEC 62852 — Connectors for DC-application in photovoltaic systems (referenced for DC connector limits) | https://webstore.iec.ch/publication/5760 |
| ALMMCS — Approved List of Models and Manufacturers (modules) | MNRE ALMMCS list (compliance gate; not a duty question) | https://mnre.gov.in/almmcs/ |
| Customs Tariff — India (HS schedule-1) | CBIC — Indian Customs Tariff (ITC-HS) schedule-1, headings 8541, 8504, 7308, 7610 | https://www.cbic.gov.in/htdocs-cbec/customs/cst2022-index |
| Customs notifications (BCD / exemption / end-use) | CBIC — Customs Notifications page (latest BCD and renewable-energy / project-import exemptions) | https://www.cbic.gov.in/htdocs-cbec/customs/customs-notifications |
| GST rate schedule — solar PV goods | CBIC GST — rate schedule and CGST/SGST/IGST notifications for solar PV goods | https://cbic-gst.gov.in/gst-notifications.html |