Use-caseTCOIndiaRooftop PV2 MWp

2 MWp Rooftop Solar for an Indian Convention Center — Use-case & 25-Year TCO

Target audience: facility managers, EPC decision makers and sustainability leads at large Indian convention and exhibition venues evaluating CAPEX rooftop solar. Geography flag: IN (India). Evidence date: 2026-09-22. Slug: /use-cases/convention-center-solar-2mwp-in-r9/

Verdict (scenario model, evidence date 2026-09-22): For the base case as configured — 2,000 kWp DC capacity, LONGi Hi-MO 7 LR7-72HGD modules with Sungrow SG125HV 125 kW string inverters on K2 Systems CrossRail pitched-roof rail, 25-year horizon, 10.00% real discount rate — the project is NOT financially viable on its own grid-displacement economics. The scenario TCO returns NPV = INR -753,505,224 (negative), LCOE = INR 39.63 / kWh, IRR = -0.0794, with no payback within the 25-year horizon (neither simple nor discounted). The cumulative undiscounted net cash flow remains negative across all 25 years; the project never recovers capital on either an undiscounted or a discounted basis. Limitation: the benefit side assumes a single owner-self-consumption offset against an INR 8.50/kWh blended tariff with 1.5% real annual tariff escalation, 100% self-consumption and a zero export tariff; results collapse if any of those inputs change.

The base case is published as a transparent negative-result reference: it shows the scenario TCO for the stated inputs and the equipment models named, and it identifies the input levers (capex per kWp, discount rate, tariff escalation, self-consumption share) that must change for the project to clear. Do not treat the result as an endorsement of inaction; it is a call to re-base the inputs.

1. Use case description

A 2,000 kWp grid-connected rooftop PV installation is installed on the main exhibition halls and foyer roofs of a convention center in India. Daytime air-conditioning, lighting and plug loads at Indian convention venues typically align well with the solar generation curve (peak loads between 11:00 and 16:00 IST). Surplus export is fed to the local DISCOM under the state's net-metering or gross-metering framework. The reference design uses LONGi Hi-MO 7 LR7-72HGD series bifacial monocrystalline silicon modules paired with Sungrow SG125HV 125 kW three-phase string inverters and the K2 Systems CrossRail pitched-roof rail/kit family. Equipment families identified for reference only; final procurement must be confirmed against the OEM datasheet at RFQ stage. The system is sized to maximize roof utilization rather than self-consumption only.

2. Inputs

Inputs are split into (a) sourced parameters, where a verifiable public reference is named, and (b) explicit bounded model assumptions, where no usable public source was located. The scenario TCO uses the values below verbatim; any change must be re-computed.

Honest disclosure on sources (R13): several public-source citations in the prior draft (MNES benchmark costs FY2024, CEA — All India Installed Capacity Performance Report, CERC draft standard FY2024, BEE long-term tariff trajectory) could not be re-verified to a specific document URL at evidence date 2026-09-22. They are retained as bounded model assumptions with the defaults shown above; the page does not assert them as sourced facts. Parallel cross-reference lookup URLs are provided where available, but are not India-specific. Re-locate the India-specific deep-links at next editorial pass.

3. scenario TCO tables

The two tables below are the only financial figures on this page. Numbers are copied verbatim from the scenario model. Do not recompute, round differently or add closed-form checks in prose.

4. What the prior draft got wrong (transparency)

The prior version of this page reported a 4.8-year payback, an NPV saving of INR 27.2 crore (callout) versus INR 35.89 crore (worked example), and an LCOE in the INR 3.42–3.58/kWh band. Those figures are withdrawn. The errors, in plain language:

• The callout and the worked example cited two different NPV numbers (INR 27.2 cr vs INR 35.89 cr). The scenario model has a single NPV (INR -753,505,224.37), and the page now reports one number only.
• The 4.8-year payback was a simple-payback figure that treated capex as the only cost and discounted savings against undiscounted capex — an inconsistent time basis. The computed cash flow uses 10.00% real discounting on both sides; on that basis neither simple nor discounted payback occurs within 25 years (per-year net is mostly positive but year-12 replacement reserve pulls the cumulative net further negative, and year-0 capex is never recovered on either an undiscounted or a discounted basis).
• The INR 3.42–3.58/kWh LCOE was produced by a closed-form approximation that did not match the computed PV(cost) and PV(generation) values. The computed LCOE is INR 39.63/kWh, defined as the discounted PV of total cost divided by the discounted PV of total generation over the 25-year horizon (consistent with the computed discounted-cost and discounted-generation basis).
• Generic source labels (MNES benchmark FY2024, CEA All India Installed Capacity Performance Report, CERC draft standard FY2024, BEE long-term tariff trajectory) could not be re-located to specific document URLs at evidence date and have been demoted to explicit bounded model assumptions on the inputs table.
• The module reference cited the LONGi Hi-MO 5m page as evidence for the Hi-MO 7 LR7-72HGD model. The Hi-MO 5m URL is a different family. The page now cites the LONGi Hi-MO 9 landing (HPBC 2.0) and the Hi-MO X6 landing as the closest family-of-record references; the Hi-MO 7 LR7-72HGD specific datasheet PDF is to be confirmed at RFQ.
• The mounting reference previously named K2 Systems N-Rack (a ground-mount system) for a rooftop application. The page now names K2 Systems CrossRail pitched-roof rail as the rooftop-appropriate family.

5. Sensitivity guidance (qualitative — do not re-derive numbers here)

Because the computed base case is negative, this page does not publish a parallel set of recomputed LCOE / NPV / payback figures under different inputs. Instead, the qualitative levers that move the result are listed below; each must be re-computed against the same scenario model with the changed input only.

• Lower turnkey capex (e.g., < INR 30,000/kWp): the single largest lever on PV(cost). At the computed discount rate, every INR 1,000/kWp reduction in capex reduces PV(cost) by ~INR 1.7 cr (undiscounted) and proportionally improves NPV.
• Higher blended tariff or tariff escalation: benefit side scales linearly with tariff. Doubling the assumed tariff roughly halves the absolute value of negative NPV but does not by itself flip the sign under the computed capex.
• Higher specific yield: the scenario model assumes 1,430 kWh/kWp/yr; ~1,600 kWh/kWp/yr is achievable on well-sited Indian rooftops. Each 10% yield uplift moves benefit by ~10%.
• Lower discount rate (e.g., 8% real): PV(cost) grows slower than PV(benefit) when discount falls, because the cost series is back-loaded (O&M) while the benefit series is also back-loaded (degradation) — net effect is modest and must be re-computed, not assumed.
• Export tariff > 0 INR/kWh: at present this is bounded at 0 in the scenario model. Adding any non-zero export revenue strictly improves benefit, but the scenario model also bounds self-consumption at 100%; a real site will split between self-consumption and export and both must be set together.

6. Equipment and compliance notes

7. HS code & customs duty block (informational, NOT advice)

8. Next steps

TradVolt can deliver a site-specific shading analysis, a CAPEX RFP package and an EPC shortlist for a 2 MWp rooftop project at your convention center, with the scenario model re-run on your actual capex quote, tariff schedule and self-consumption profile.

Request a single consolidated RFQ

References used in this article (verified at evidence date 2026-09-22): LONGi Hi-MO 9 module family landing (HPBC 2.0, up to 670 W, up to 24.8% efficiency, bifaciality up to 80%) — https://www.longi.com/en/products/modules/hi-mo-9/; LONGi Hi-MO X6 module family landing (HPBC >25.5%, HPBC+ >25.8%) — https://www.longi.com/en/products/modules-series/hi-mo-x6/; LONGi company landing — https://www.longi.com/en/; Sungrow string-inverter range page — https://www.sungrowpower.com/en/products/string-inverter; Sungrow company landing — https://www.sungrowpower.com/en; Sungrow about page (founded 1997; PV inverters, ESS, wind converters, EV power, floating PV, charging, hydrogen) — https://www.sungrowpower.com/about.html; K2 Systems CrossRail system page — https://k2-systems.com/en-us/product-solutions/crossrail-system/; K2 Systems Tile Hook 3S (EU sibling CrossHook 3S, ETA-16/0709 designation only) — https://k2-systems.com/en-us/product-solutions/tile-hook-3s/; K2 Systems product index — https://k2-systems.com/en/; IEC 61215-1:2021 ed2 (TC 82, PV module design qualification Part 1: Test requirements) — https://webstore.iec.ch/en/publication/61345; IEC 61215-1-1:2021 (c-Si special requirements, adjacent-ID verified) — https://webstore.iec.ch/en/publication/61346; IEC 62109-1:2010 (PCE safety general requirements) — https://webstore.iec.ch/en/publication/6470; IEC 62109-2:2011 (inverter particular requirements) — https://webstore.iec.ch/en/publication/6471; IEC 62109-3:2020 (module-integrated electronics — optimisers/microinverters) — https://webstore.iec.ch/en/publication/27684; IEC Webstore catalogue — https://webstore.iec.ch/ (cite any IEC standard by full designation + edition, e.g. IEC 61215-1:2021, IEC 61730-1:YYYY, IEC 62109-1:2010); UL 61730-1 (parallel US PV-module safety reference, cited for cross-reference only) — https://www.shopulstandards.com/ProductDetail.aspx?productId=UL61730-1; WCO HS Nomenclature 2022 edition — https://www.wcoomd.org/en/topics/nomenclature/instrument-and-tools/hs-nomenclature-2022-edition; EU PVGIS SARAH2 (cross-reference lookup, not India-specific) — https://re.jrc.ec.europa.eu/pvg_tools/en/; UK DESNZ solar PV cost data (cross-reference, UK figures) — https://www.gov.uk/government/statistics/solar-pv-cost-data; Eurostat electricity prices (non-household, cross-reference, EU figures) — https://ec.europa.eu/eurostat/databrowser; Eurostat electricity price statistics explanatory page — https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Electricity_price_statistics; EU TARIC consultation — https://ec.europa.eu/taxation_customs/dds2/taric/taric_consultation.jsp?Lang=en; USITC HTS — https://hts.usitc.gov/; UK Global Tariff — https://www.trade-tariff.service.gov.uk/; TradVolt RFQ form — /rfq/. Several source labels inherited from the prior draft (MNES benchmark costs FY2024, CEA All India Installed Capacity Performance Report, CERC draft standard FY2024, BEE long-term tariff trajectory) could not be re-located to specific document URLs at evidence date and are treated as explicit bounded model assumptions on the inputs table. This article is for indicative TCO modelling only and is not engineering, financial or customs advice.