How to Choose a Solar Installer in India: 12 Questions Before You Sign

When you install rooftop solar on your home or commercial building, you are not buying a simple home appliance. You are commissioning a miniature power generation plant that must operate exposed to intense sun, monsoons, high-velocity winds, and thermal cycling for 25 to 30 years. Yet many consumers evaluate solar proposals on a single metric: the lump-sum price quoted per kilowatt.

That single metric conceals significant risks. In the Indian market, two contractors can quote for a 5 kW system with identical headline capacity, yet one quote is ?35,000 cheaper. That discount is almost always achieved by downgrading mounting structures to thin sheet metal, using domestic AC wires instead of UV-resistant solar DC cables, eliminating surge protection devices, or omitting chemical earthing pits.

When those shortcuts fail two years later, the cut-price contractor has vanished, leaving you with an underperforming system, recurring inverter faults, or a stalled DISCOM net-metering application. Use this 12-question checklist to thoroughly evaluate any solar EPC installer before signing an agreement.

Why Your Choice of Installer Matters More Than Panel Brand

Much of solar marketing emphasizes panel brands and cell technologies like TOPCon and Mono PERC. While quality modules are critical, they represent only half of a reliable power plant. Even a high-grade panel with a 30-year performance warranty will fail to deliver its expected 4 to 4.5 units per kW daily if strings are designed incorrectly, cables suffer high voltage drops, or modules are paired with an undersized inverter.

A solar installation requires coordinated structural, electrical, and regulatory expertise: civil engineering for 150 km/h wind resistance, DC electrical design for fire safety, and distribution utility liaison for net-metering approvals. Choosing the right installer is the single most important factor determining your 25-year energy yield.

Company Credentials and DISCOM Registration

1. Are you an empaneled vendor under PM Surya Ghar?

For residential subsidies under PM Surya Ghar: Muft Bijli Yojana (?30,000 for 1 kW, ?60,000 for 2 kW, and up to ?78,000 for 3 kW and above), your installer must be registered on the national portal (pmsuryaghar.gov.in). Unregistered electricians cannot upload commissioning reports or trigger the direct subsidy credit into your bank account. Always verify their national vendor ID before paying a deposit.

2. How long have you operated locally, and where is your registered office?

Digital aggregators often book orders online and subcontract labor to transient crews, leaving homeowners without local support when faults occur. Verify that the company has a physical registered office, local parts warehousing, and full-time technicians. An established regional footprint?such as Ray2Volt's registered office in Srikalahasti and operating points across Tirupati, Puttur, and Pichatur?ensures long-term accountability.

3. Who handles DISCOM net-metering approvals and clearances?

Physical panel mounting takes only two to three days; the real bottleneck is utility grid synchronization. Securing technical feasibility approval, arranging bi-directional net meters, coordinating DISCOM inspections, and obtaining electrical clearances requires dedicated regulatory coordination. A professional EPC manages this entire workflow turnkey.

System Design, Hardware Selection, and Bill of Materials

4. Which specific panel and inverter models are in the Bill of Materials?

Never accept vague proposals stating "5 kW Tier-1 Panels". Insist on a line-item Bill of Materials (BoM) stating the exact manufacturer, model number, rated wattage per module, cell architecture, and inverter efficiency rating. This prevents bait-and-switch tactics where high-end hardware is quoted but discontinued stock is delivered.

5. Are the modules DCR compliant and listed on MNRE's ALMM List-I?

To qualify for residential subsidies under PM Surya Ghar, MNRE mandates Domestic Content Requirement (DCR) modules where cells and modules are manufactured in India, listed on ALMM List-I. Following the June 2026 ALMM List-II compliance shift, even new commercial and industrial solar installations are predominantly engineered with DCR panels. Ask your installer for the module datasheet and flash test report with RFID barcodes.

6. What structure engineering and wind rating do you use?

In South India, rooftops face extreme seasonal wind gusts during cyclones and summer squalls. Mounting structures must be engineered to withstand wind speeds of at least 150 km/h using hot-dip galvanized iron (HDGI) with an 80+ micron zinc coating or structural aluminium. Avoid pre-galvanized pipes with thin 15-micron coatings that rust within two seasons.

7. How are DC cabling, earthing pits, and surge protection designed?

Substandard DC hardware is the leading cause of rooftop electrical faults. Ensure your installer provides UV-resistant XLPO-insulated tinned copper solar DC cables, dedicated chemical earthing pits with copper-bonded electrodes (separate pits for DC array grounding, inverter AC grounding, and lightning protection), and genuine Type-II Surge Protection Devices (SPD) in both DC and AC distribution boxes.

Warranties, Service Commitments, and After-Sales Support

8. Who honours the equipment warranties and provides local service?

A solar installation carries three warranty layers: a 30-year panel performance warranty, a 7?10 year inverter warranty, and the installer's workmanship warranty. As detailed in our guide to decoding solar warranties, verify whether your installer handles warranty claims directly or expects you to courier heavy equipment to factory service centers.

9. What is your guaranteed response time during an inverter fault?

Every day your system remains offline represents lost savings. In summer, a 10 kW plant generates 40 to 45 units daily. Demand a documented Service Level Agreement (SLA) with a 24-to-48-hour response window and qualified local service technicians.

10. Is remote generation monitoring included and configured?

Modern inverters feature Wi-Fi or 4G monitoring modules that transmit real-time generation data to your smartphone. Ensure your installer sets up this monitoring portal during handover so you can track daily unit generation and detect faults immediately.

Pricing Transparency, Milestones, and Subsidy Processing

11. Is the quote turnkey or are there hidden net-metering and transport costs?

Low-cost proposals often omit crane charges, bi-directional net meter testing fees, and DISCOM application costs. Ensure your quotation is 100% turnkey and explicitly covers all statutory approvals, meter calibration, freight, and commissioning expenses.

12. What is the milestone payment schedule tied to installation stages?

Never agree to 100% advance payment. A fair payment structure aligns cash flow with physical progress and protects both parties.

Comparing Installer Types: Cut-Price Contractors vs Professional EPCs

To understand why quotation prices differ, examine how different categories of solar vendors approach system design, hardware sourcing, and ongoing service support:

6 Warning Signs That Should Make You Walk Away

If you encounter any of the following warning signs during vendor discussions, pause immediately and seek alternative proposals:

• Demanding 100% Payment Upfront: Legitimate contractors have credit lines to execute project milestones before final settlement.
• Vague Quotations: Omitting exact module models and switchgear brands leaves room to substitute inferior components.
• Unrealistic Generation Claims: A realistic generation rule of thumb is 4 to 4.5 units per kW per day annual average (1,400 to 1,600 units per kW annually). Claims above 6 units daily are misleading.
• No Local References: Reputable installers readily provide references of operational systems in your district.
• No Physical Office: Operating exclusively via mobile makes warranty enforcement nearly impossible.
• Refusing Stamped Workmanship Warranties: Roof waterproofing, structural stability, and electrical workmanship must be guaranteed in writing by the installer.

Before selecting a contractor, ensure your roof is properly evaluated using our guide on how to size a solar system. Homeowners in Andhra Pradesh should also consult our local breakdown of going solar in Tirupati and Srikalahasti. If you require continuous power during grid outages, explore our residential hybrid solar solutions or compare system types across our complete residential solar portfolio.

Frequently asked questions

Ray2Volt Solar Private Limited

We design, install, and service rooftop solar for homes and businesses across Tirupati district and Andhra Pradesh ? from PM Surya Ghar residential systems to commercial and industrial plants. Every enquiry starts with a free power audit.