--- title: How to Choose a Solar EPC in India | Arrays Ingenieria description: 12 questions to ask before hiring a solar EPC or installation partner in India: track record, documents, equipment, safety, approvals and warranties. url: https://arraysingenieria.com/choose-solar-epc-partner/ last_updated: 2026-10-11 source: Arrays Ingenieria (Arrays Ingenieria Pvt. Ltd.) --- Guide · Buyer's Guide # How to Choose a Solar EPC and Installation Partner in India: 12 Questions to Ask The partner you choose decides how your plant performs for 25 years. Twelve questions to ask any solar EPC or installation contractor, what good answers look like, and the red flags to walk away from. On this page - Why the partner matters more than the panel - The 12 questions - Red flags - How to compare quotations fairly - Our answers - Frequently asked questions - Sources By the [Arrays Ingenieria engineering team](https://arraysingenieria.com/about/) · Updated 11 Oct 2026 · 3 min read **Key takeaways** - Ask for **documented** projects: purchase orders, client certificates and site visits, not just photos - Check who will actually be on site: in-house crews and supervisors, or labour subcontracted at the last minute - Insist on ALMM-listed modules and BIS-certified inverters named in the contract - Ask how the contractor handles safety, approvals (DISCOM, CEIG) and testing at handover - Compare quotations on the same specification; the cheapest bid often hides thinner cables, weaker structures or missing items ## Why the partner matters more than the panel Two plants built with identical modules can perform very differently. Structure design, cable sizing, earthing, string layout, workmanship at every connector and the quality of commissioning tests decide how much power the plant makes and how safely it runs for 25 years. That is the contractor's work. ## The 12 questions Questions to ask a solar EPC or installation partner | # | Question | A good answer looks like | | --- | --- | --- | | 1 | Which comparable plants have you built? | Named projects of similar size and type, with locations and dates | | 2 | Can I see purchase orders, completion or appreciation certificates? | Documents from clients and EPC majors, and references you can call | | 3 | Who will be on site? | Named project manager and site engineer; in-house crews for critical work | | 4 | Which modules and inverters, exactly? | Make, model and ALMM / BIS status written into the contract | | 5 | How is the structure designed? | Wind-load design for your location, galvanising spec, roof or pile calculations | | 6 | How are cables sized and routed? | Voltage-drop calculation, UV-resistant DC cable, proper trays and glands | | 7 | How do you earth and protect the plant? | Separate DC and AC earthing, lightning protection, surge devices, tested earth resistance | | 8 | Who handles approvals? | The contractor files DISCOM, net-metering and CEIG paperwork | | 9 | What tests will you hand over? | Insulation resistance, polarity, string Voc/Isc, earth resistance, inverter settings, as-built drawings | | 10 | What is your safety system? | Permits, PPE, work-at-height and electrical isolation procedures, toolbox talks, ISO 45001 | | 11 | What warranties and guarantees? | Manufacturer warranties passed on, workmanship warranty, performance commitment | | 12 | What happens after handover? | O&M or module-cleaning options, a contact for faults, response times | ## Red flags - "Tier-1 equivalent" modules or unnamed inverters in the quotation - No earthing or lightning-protection design, or a lump sum for "BOS" with no detail - A price far below others on the same specification - No site visit before quoting - Reluctance to put approvals, testing or handover documents in the contract ## How to compare quotations fairly - **Fix the specification**Capacity (kWp DC and kW AC), module and inverter class, structure type, cable sizes. - **Ask for a bill of quantities**Line items for modules, inverters, structures, cables, earthing, LA, ACDB/DCDB, civil works, approvals. - **Compare like with like**Normalise each quote to the same scope; add the missing items to the cheaper ones. - **Check the generation estimate**The same location and assumptions should give similar yields; an outlier needs explaining. - **Read the contract**Payment milestones tied to progress, delay and performance clauses, warranty start dates. ## Our answers Arrays Ingenieria is an ex-servicemen-led company certified to ISO 9001, ISO 14001 and ISO 45001. Our [projects page](https://arraysingenieria.com/projects/) lists our work, and our case studies carry the client certificates and press coverage behind them. We do not manufacture modules or inverters, so we specify and document the makes your project requires. Our team with the Chief Minister of Assam at the Koomber Tea Estate plant, 1 October 2026. Put our answers to the test: ask us all 12 questions about your project. [Get a free solar quote](https://arraysingenieria.com/free-solar-quote/) ## Frequently asked questions How do I check a solar EPC company's track record? Ask for named projects of similar size, client purchase orders or certificates, and references you can call. Visit a working plant if you can. Should the EPC contract name the module and inverter brands? Yes. The make, model and certification (ALMM for modules, BIS for inverters) should be written into the contract and the bill of quantities. What documents should I get at handover? As-built drawings, test reports (insulation, polarity, string voltages and currents, earth resistance), inverter settings, warranty certificates, approvals and an O&M manual. Is the cheapest solar quote a bad idea? Not always, but compare quotations on the same specification and bill of quantities. Large price gaps usually come from thinner cables, lighter structures or missing items. ## Sources - [PIB: MNRE notifies the revised Quality Control Order for solar photovoltaic products](https://www.pib.gov.in/PressReleasePage.aspx?PRID=2097219) - [PIB: MNRE amends the ALMM Order 2019 (List-II for solar cells)](https://www.pib.gov.in/PressReleasePage.aspx?PRID=2082901) This guide explains public policy in plain language for planning purposes. Rules, rates and deadlines change: confirm the current position with the notifying authority, your DISCOM and your tax adviser before you commit. Last checked 11 Oct 2026. **About the authors.** Arrays Ingenieria is an ex-servicemen-led solar EPC and installation & commissioning company working Pan-India, from Assam's tea estates to industrial rooftops. [Our story](https://arraysingenieria.com/ex-servicemen-led-msme/) · [Our projects](https://arraysingenieria.com/projects/) [CAPEX Solar EPC](https://arraysingenieria.com/capex-solar-epc/)[Installation & Commissioning](https://arraysingenieria.com/solar-installation-commissioning/)[Quality & Safety](https://arraysingenieria.com/quality-safety/) From Our Sites ## Case Studies on This Topic Real plants our veteran-led crews have built, with the scope of work in detail. [Tea Estate · Inaugurated by the CM: **Koomber Tea Estate: 595 kWp Solar Plant, Inaugurated by the Chief Minister of Assam**595 kWp · Koomber Tea Garden, Silchar, Cachar district (Barak Valley), AssamRead the case study](https://arraysingenieria.com/project-koomber-tea-estate-595kwp-solar-cm-inauguration/)[Industrial · Rooftop: **Super Smelters: 1980.3 kWp Rooftop Solar Plant**1980.3 kWp (about 2 MW) · Jamuria (Asansol), West BengalRead the case study](https://arraysingenieria.com/project-super-smelters-1980kwp-rooftop-solar/)[Tea Estates · Multi-Site I&C: **Amalgamated Plantations, Assam: Solar Across Tea Estates**About 5 MW across tea estates (3.8 MWp piled at 11 sites) · Chubwa, Kakajan, Powai, Nonoi, Diffloo, Nahortoli, Naharkatia, Namrup, Borhat and other estates, AssamRead the case study](https://arraysingenieria.com/project-amalgamated-plantations-assam-tea-estates-solar/) Keep Reading ## Related Guides [Business Models: **CAPEX vs OPEX (RESCO) Solar: Which Model Suits Your Business?**Own your solar plant and keep every unit, or pay a developer per unit with no upfront cost? A side-by-side comparison of CAPEX and OPEX solar, with the numbers that decide it.3 min read · Updated 11 Oct 2026](https://arraysingenieria.com/capex-vs-opex-solar/)[Standards & Safety: **Solar Quality and Safety Norms in India (2026): BIS, the Quality Control Order, CEA and CEIG**What makes a solar plant compliant in 2026: the BIS Quality Control Order for modules, inverters and batteries, the standards each component should meet, the Electrical Inspector's approval, and site safety.3 min read · Updated 11 Oct 2026](https://arraysingenieria.com/solar-quality-standards-bis-cea/)[Installation & Commissioning: **Solar Plant Installation and Commissioning: The Complete Step-by-Step Checklist**What actually happens between the purchase order and the day a solar plant goes live. Every stage of installation and commissioning, the tests that prove the plant is safe, and the documents you should receive at handover.3 min read · Updated 11 Oct 2026](https://arraysingenieria.com/solar-plant-commissioning-checklist/) [All solar guides](https://arraysingenieria.com/insights/)[Government solar schemes](https://arraysingenieria.com/solar-schemes-india/)