What project owners need to know.
A solar module's bill of materials (BOM) is the list of everything laminated and fitted around the cells: front solar glass, encapsulant films, a rear backsheet or second glass, an aluminium frame, a junction box, plus ribbons and sealants. In India these non-silicon inputs are only partly localised. A September 2026 Centre for Science and Environment (CSE) study puts domestic solar glass capacity at 15–18 GW. It reports that about 95% of aluminium frame requirements are imported. It also finds POE encapsulants, which n-type TOPCon modules increasingly use, almost entirely import-dependent, while PET backsheets and EVA films have a modest domestic base. Anti-dumping duties already apply to Chinese and Vietnamese solar glass and to Chinese aluminium frames, and encapsulant investigations are open. For module and cell makers, the practical point is that localisation is not finished at the cell: each BOM material needs its own qualified, traceable supply route.
What sits around the cell
A conventional crystalline silicon module is a laminate. Cells are interconnected with ribbons and sandwiched between two layers of encapsulant film. Tempered, textured low-iron solar glass sits in front, and a polymer backsheet or a second sheet of glass sits behind. The laminate is then framed in aluminium and fitted with a junction box that carries the electrical output. CSE's 2026 landscape study describes this stage as interconnecting cells and encapsulating them within glass, polymer encapsulants and frames.
None of these parts makes electricity, but together they decide whether the cells survive decades of heat, humidity, ultraviolet light, mechanical load and voltage stress. That is why BOM changes trigger requalification, and why a module maker's materials list is as much a reliability document as a purchasing one.
- Front: textured, tempered low-iron solar glass
- Encapsulant: EVA, POE or co-extruded EPE films on both sides of the cells
- Rear: polymer backsheet (glass-backsheet) or a second glass (glass-glass)
- Frame and junction box: mechanical strength, mounting and electrical output
- Any change to this stack is a reliability change, not only a sourcing change
Where India stands, component by component
CSE reviewed India's position as of July 2026 and notes a data problem first: most solar inputs have no dedicated HS code, so the most reliable component-level evidence comes from DGTR trade-remedy investigations and company disclosures. With that caveat, its picture is uneven. Solar glass has the most developed domestic base, at 15–18 GW of capacity with another 20–22 GW in the pipeline, led by one established producer and a second emerging one.
Backsheets and encapsulants have a modest domestic base for conventional PET backsheets and EVA films, with several Indian manufacturers named in the study. Higher-value materials are different. Fluoropolymer (PVF/PVDF) backsheets rely on imported raw materials, and POE encapsulants are described as almost entirely import-dependent. Aluminium frames are the weakest link by volume: industry reports cited by CSE put imports at around 95% of current requirements, although dedicated domestic frame plants now operate and more capacity is expected. CSE adds that those plants themselves depend on imported extrusion presses and anodising lines. Metallisation paste, covered in our silver guide, remains almost entirely imported.
- Solar glass: most localised BOM item, still competing with imports from China and South-East Asia
- EVA films and PET backsheets: modest domestic base
- POE encapsulants and fluoropolymer backsheets: largely import-dependent
- Aluminium frames: domestic plants emerging, most volume still imported
- Junction boxes: listed by CSE among components still partly or substantially imported
Trade remedies shaping the BOM market
India has used anti-dumping duties to protect early domestic BOM capacity. For solar glass, the finance ministry notified a five-year duty of USD 570 to 664 per tonne on textured tempered solar glass from China and Vietnam, running from the provisional duty date of 4 December 2024, as reported by PTI in May 2025. CSE notes that duties on Chinese and Vietnamese solar glass date back to 2019, and that separate restrictions on imports from Malaysia and Indonesia have been extended to 2031.
For frames, Customs Notification No. 16/2024-Customs (ADD), dated 27 September 2024, imposed anti-dumping duty on anodised aluminium frames for solar panels and modules from China. It followed DGTR findings that dumped imports had materially retarded the establishment of the domestic industry. CSE reports the duty at USD 403 to 577 per tonne for five years. For encapsulants, an anti-dumping duty already applies to EVA sheets from China. TaiyangNews reported in September 2025 that DGTR had opened a further investigation into POE, EPE and EVA encapsulants from South Korea, Thailand and Vietnam, and CSE notes a separate probe into non-EVA encapsulants from China.
- Duties change landed prices and supplier choices, not material specifications
- Check whether an open investigation could affect a BOM item's landed price during the contract period
- Confirm current duty status on official CBIC and DGTR notifications before quoting
- Expect suppliers to shift origin; qualify the material, not only the country
Why n-type cells are changing the materials list
BOM choices follow cell technology. pv magazine reported as early as 2021 that bifacial glass-glass modules were driving a switch from EVA towards POE, mainly because of a potential-induced degradation (PID) mechanism on the rear of bifacial cells, and because EVA can release acetic acid as it ages. The same report noted that POE is harder to process, with longer lamination cycles and a narrower process window, which is why co-extruded EVA-POE-EVA (EPE) films emerged as a compromise.
India's cell lines are now moving from PERC to n-type TOPCon, which CSE says increasingly requires POE-based encapsulants. The material most exposed to imports is therefore the one the technology shift makes more important. A module maker localising cells under ALMM List-II, or planning for wafers under ALMM List-III from June 2028, still depends on a materials stack that is only partly domestic.
- Glass-glass bifacial designs raise the importance of encapsulant choice
- POE and EPE need lamination recipes qualified for them, not copied from EVA
- Encapsulant and backsheet changes should go through accelerated reliability testing
- Re-check encapsulant compatibility whenever cell technology or paste changes
What module and cell makers should plan
CSE's study frames the wider gap plainly. India lists about 219 GW of module capacity under ALMM List-I against roughly 2 GW of ingot and wafer capacity. It describes no allied supplier ecosystem at scale, which means integrated makers carry each stage on their own balance sheet. BOM localisation sits alongside the upstream silicon gap: both decide how much of a module made in India is actually made in India.
In practice, BOM materials deserve the same discipline as cells and wafers. Specify each material by its function and test results, qualify more than one source, keep lot traceability into the laminate, and treat a change of supplier or origin as an engineering change. Where domestic options exist, qualify them early. Many of these suppliers are still scaling, and qualification cycles are long. Policy and duty positions should always be confirmed against current MNRE, DGTR and CBIC documents.
- Write material specifications and acceptance tests for every BOM item
- Qualify at least two sources, including a domestic one where available
- Link BOM lot numbers to module serial numbers for traceability
- Re-run reliability testing when encapsulant, backsheet or glass changes
- Review duty and ALMM status before long-term supply contracts
How JRST supports this requirement
JRST supports solar manufacturing projects in planning materials and consumables across the chain, from silicon feedstock and crucibles to the module materials stack: specifications, supplier qualification, acceptance testing and traceability. Figures on this page are drawn from public research, government notifications and trade reporting, and should be validated for the specific project; duty, ALMM and compliance positions change and must be confirmed with the relevant authorities.
Discuss your requirement
Mohammed Saif Zaveri connects JRST's industrial content to execution conversations.
As Co-Founder and designated partner of JRST Technology LLP, Mohammed Saif Zaveri works across industrial growth, strategic partnerships, client conversations, equipment strategy, and project pathways for silicon, solar, semiconductor, and advanced-manufacturing opportunities.
This knowledge page is part of JRST's public industrial knowledge base, designed to help buyers move from search terms and early research toward a structured technical-commercial discussion.
View Mohammed Saif Zaveri's profileConnect on LinkedInFrequently asked questions
What is a solar module bill of materials (BOM)?
It is the list of materials that make up a module besides the cells: front solar glass, encapsulant films, a backsheet or rear glass, an aluminium frame, a junction box, ribbons and sealants. Together they protect the cells and carry their output.
Which solar module components does India still import?
According to CSE's 2026 study, POE encapsulants, fluoropolymer backsheet materials, most aluminium frames and nearly all metallisation paste are imported, and junction boxes are partly imported. Solar glass, EVA films and PET backsheets have a domestic base.
How much solar glass can India make?
CSE puts domestic solar glass manufacturing capacity at 15–18 GW, with a further 20–22 GW in the pipeline, as of its 2026 review.
Is there an anti-dumping duty on solar glass in India?
Yes. A five-year duty of USD 570 to 664 per tonne applies to textured tempered solar glass from China and Vietnam, counted from the provisional duty date of 4 December 2024, as reported in May 2025. Check current notifications before relying on it.
Why are TOPCon and bifacial modules using POE instead of EVA?
POE is more resistant to moisture and does not release acetic acid as EVA can. It also helps control potential-induced degradation on the rear of bifacial cells. It is harder to laminate, so EPE films are a common compromise.
Does ALMM cover module BOM materials such as glass or frames?
ALMM List-I covers modules and List-II covers cells, and List-III is proposed for ingots and wafers from June 2028. BOM materials are shaped mainly by trade remedies and customer specifications rather than ALMM lists. Confirm current rules directly with MNRE.
How can JRST help?
JRST can help module, cell and wafer projects map their materials and consumables, set specifications and acceptance tests, and plan supplier qualification and traceability. Outcomes remain project-specific and must be validated.
Primary sources and further reading
Last reviewed 2026-10-08. Technical scope, policy eligibility, availability, and commercial terms should be independently confirmed for each project.