Modules are about a third or more of a rooftop system's cost and the part that must last longest. Choosing them is partly technical (efficiency, temperature behaviour, size) and partly regulatory: in India, the wrong module can make a customer lose their subsidy or the DISCOM refuse the net meter.
DCR and non-DCR
DCR (domestic content requirement) modules use solar cells and modules made in India. Each DCR module comes with a manufacturer's DCR certificate listing its serial number, which is verified for subsidy claims.
Non-DCR modules are assembled in India (or imported) using imported cells.
| DCR | Non-DCR | |
|---|---|---|
| Cells | Made in India | Imported |
| Needed for | PM Surya Ghar CFA, PM-KUSUM and other government-supported schemes | Projects without such support |
| Price (Sunlectric catalogue, October 2026, ex-GST, 550 Wp PERC) | ₹14,300 (about ₹26 per Wp) | ₹8,520 (about ₹15.5 per Wp) |
Worked example: does DCR pay for a home?
A 3.3 kWp home system needs 6 modules.
- Extra cost of DCR: 6 × (14,300 − 8,520) = ₹34,680 (plus 5% GST on modules)
- PM Surya Ghar CFA, available only with DCR: ₹78,000
DCR wins by over ₹40,000. For residential customers taking the subsidy, DCR is not a choice; it is a condition.
For a commercial rooftop with no CFA, the cheaper module may be allowed, but check the ALMM rules below first.
ALMM: the approved list
MNRE keeps the Approved List of Models and Manufacturers (ALMM):
- List-I covers modules: manufacturer, factory and model.
- List-II covers cells. It took effect on 1 June 2026 for government schemes, net-metering and open-access projects, with some cut-off dates and limited exemptions (MNRE orders of 2024–2025 and later clarifications).
For example, MNRE has clarified that residential net-metering consumers under PM Surya Ghar who choose the "Give It Up" option (forgoing CFA) need not use ALMM List-II cells until 31 March 2027. These rules have changed several times, so check the current MNRE order before quoting any net-metered project with non-DCR modules.
What to do on every job:
- Confirm the exact model number is on ALMM List-I.
- For projects covered by List-II, confirm the cell supplier is listed (DCR modules satisfy this through their certificate).
- Keep screenshots or printouts of the listing with the project file.
BIS registration
Modules sold in India must be registered with BIS under the compulsory registration order for solar products, tested to IS 14286 (equivalent to IEC 61215) and IS/IEC 61730. The label carries a registration number (R-number). You can verify it on the BIS registration portal.
Warranties: read the conditions
Modules usually carry two warranties.
Product (workmanship) warranty
Covers defects in materials and manufacture: delamination, junction box failure, broken frames, backsheet cracking. Typical terms are 10–15 years; some makers offer 25 or 30.
Performance warranty
Guarantees minimum power output over time, usually linear:
The difference over 25 years is about 4.6 percentage points of output, worth real money over the system's life.
Read the warranty document, not just the datasheet. Look for:
- Who claims and how. Usually through the installer, with flash-test evidence from an accredited lab.
- Exclusions. Installation outside the manual (clamping zones, wrong connectors), salt-mist damage on non-certified modules near the sea, and transport damage.
- Remedy. Repair, replacement or a cash payment for the shortfall. Replacement modules may be a different model.
- Company presence. A 30-year warranty from a company with no Indian office is worth little.
Quality checks before you choose a supplier
Ask for these documents for the exact model:
| Document | What it shows |
|---|---|
| IEC 61215 / IS 14286 and IEC 61730 test reports or certificates | Design qualification and safety |
| BIS registration (R-number) | Legal to sell in India |
| ALMM listing (and DCR certificate if DCR) | Eligible for schemes and net metering |
| Flash test report per serial number | Actual power of each module (should be at or above nameplate) |
| EL (electroluminescence) images | Micro-cracks and broken fingers invisible to the eye |
| PID test (IEC TS 62804-1) | Resistance to potential-induced degradation, which matters at high string voltage in humid areas |
| Salt mist (IEC 61701) | Needed within a few kilometres of the coast: Chennai, Mumbai, Visakhapatnam, Kochi |
| Ammonia (IEC 62716) | Dairy sheds, poultry farms |
| Sand and dust (IEC 60068-2-68) | Desert sites in western Rajasthan and Kutch |
Practical selection points
- Size and weight. Large 2.28 m, 28 kg modules are efficient but awkward to carry up narrow Mumbai or Kolkata staircases. Smaller formats (around 1.7 m) suit tiny terraces.
- Efficiency. Higher efficiency matters when roof area limits the system (module m01).
- Temperature coefficient. TOPCon and HJT lose less in hot cities like Nagpur, Jaipur or Chennai.
- Current rating. Modern modules produce 13–18 A. Check the inverter's maximum input current per MPPT (lesson 2).
- Stock and service. Can the supplier deliver the same model again in a year if a module breaks?
Key points
- DCR modules use Indian cells and modules; they are mandatory for PM Surya Ghar CFA and cost more, but the subsidy far outweighs the premium.
- ALMM List-I (modules) and List-II (cells, from 1 June 2026) control which products can be used on schemes and net-metered projects; check the current order.
- Verify BIS registration and the exact model's certificates, not just the brand.
- Read warranty exclusions, claim procedures and the company's local presence.
- Ask for flash test data, EL images, and salt-mist, ammonia or sand tests where the site needs them.
Check yourself
- A customer wants the cheapest modules for a subsidised 3 kW home system. What do you tell them?
- Which test matters most for a rooftop 2 km from the sea in Chennai?
- What is the warranted output of a PERC module (98% in year 1, −0.55% a year) at year 15?
Answers
- Only DCR, ALMM-listed modules qualify for the CFA. Cheaper non-DCR modules would lose the ₹78,000 subsidy, so the DCR option is cheaper overall.
- Salt-mist corrosion testing to IEC 61701 (and check that the warranty covers coastal sites).
- 98 − 0.55 × 14 = 90.3%.