Solar PV Encapsulant Regulations in India 2026: EVA vs POE, BIS Standards, Testing and What Manufacturers Need to Know
A practical guide to EVA, POE and EPE encapsulants, Indian PV-module standards, BIS requirements, testing, qualification and QA/QC considerations.
The solar PV encapsulant is a critical component of a photovoltaic module. Although India does not currently have a blanket MNRE requirement mandating one specific encapsulant chemistry such as EVA, POE or EPE, encapsulants are covered within the broader PV-module safety, qualification and reliability framework.
- No blanket MNRE mandate requiring only EVA, POE or EPE has been identified.
- Encapsulants form part of the PV-module construction and safety framework.
- IS/IEC 61730:2023 contains specific encapsulant-related requirements.
- Encapsulant optical, electrical, thermal and durability properties are increasingly important in qualification.
- EVA, POE and EPE should be selected according to the complete module design and reliability requirements.
- A change in encapsulant material or supplier should be controlled through appropriate qualification and engineering change procedures.
- What Is a Solar PV Encapsulant?
- Is There a New Indian Encapsulant Rule in 2026?
- BIS and PV Encapsulant Requirements
- What Is EVA Encapsulant?
- What Is POE Encapsulant?
- What Is EPE Encapsulant?
- EVA vs POE vs EPE
- Optical Properties
- Electrical Properties
- Thermal Properties
- Moisture Resistance
- Encapsulants and PID
- Encapsulant IQC Requirements
- Lamination Process Control
- Material vs Module Qualification
- Does ALMM Specify Encapsulant?
- What Indian Manufacturers Should Do
- Frequently Asked Questions
- Conclusion
What Is a Solar PV Encapsulant?
A photovoltaic encapsulant is a polymeric material used to encapsulate solar cells inside a PV module. It is positioned between the cells and the module's protective layers.
Depending on the module architecture, the basic construction can be represented as:
The encapsulant performs several functions simultaneously.
- Protects cells from environmental exposure.
- Provides electrical insulation.
- Provides optical coupling between the cell and glass.
- Helps hold cells and interconnections in position.
- Supports mechanical protection.
- Contributes to long-term module reliability.
Is There a New Indian Encapsulant Rule in 2026?
This is the most important point for manufacturers to understand.
Based on the current MNRE and BIS information reviewed for this article, there is no blanket MNRE requirement mandating one particular PV encapsulant chemistry such as EVA, POE or EPE for all solar modules.
In other words, the current framework does not establish a general rule stating that:
- Only EVA can be used.
- Only POE can be used.
- Only EPE can be used.
- A specific encapsulant brand must be used.
Important: The absence of a chemistry-specific mandate does not mean that any encapsulant can be used without qualification. The encapsulant remains part of the finished PV module's safety, reliability and qualification system.
BIS and PV Encapsulant Requirements
The Bureau of Indian Standards plays an important role in India's PV-module conformity and standards framework.
BIS records for IS/IEC 61730:2023 include encapsulant-related requirements under PV-module construction.
This is significant because the encapsulant is not treated simply as an ordinary consumable. Its suitability is connected to the construction and safety of the complete PV module.
BIS documentation also contains encapsulant-related considerations involving properties such as thermal behaviour and insulation.
Why Encapsulant Qualification Matters
A PV module is a system made from multiple materials that interact during manufacturing and throughout the module's operating life.
The encapsulant interacts with:
- Solar cells
- Glass
- Ribbons
- Interconnects
- Backsheet or rear glass
- Adhesives
- Junction-box interfaces
Therefore, material qualification should consider the complete module construction rather than only the polymer in isolation.
What Is EVA Encapsulant?
Ethylene Vinyl Acetate (EVA) is one of the most established encapsulant materials used in photovoltaic modules.
EVA has a long history in PV manufacturing and benefits from mature manufacturing processes and broad industry experience.
Advantages of EVA
- Long industry track record
- Established lamination processes
- Broad supplier availability
- Good optical performance
- Extensive module qualification experience
Important Consideration
EVA formulations can generate acetic acid during certain degradation pathways. Therefore, formulation, module construction and environmental exposure need to be considered when evaluating long-term reliability.
What Is POE Encapsulant?
Polyolefin Elastomer (POE) has become increasingly important with advanced PV module technologies.
POE is particularly discussed in relation to its low moisture-permeability characteristics and electrical insulation properties.
Potential Advantages of POE
- Low moisture permeability
- Strong electrical insulation characteristics
- Potential advantages against certain PID mechanisms
- Suitability for advanced module architectures
POE is increasingly relevant in discussions around TOPCon, HJT and other n-type module technologies.
What Is EPE Encapsulant?
EPE generally refers to a multilayer encapsulant structure combining EVA and POE layers.
A commonly discussed structure is:
The exact formulation and layer construction can vary between suppliers.
EPE can therefore provide a balance of selected characteristics associated with EVA and POE.
EVA vs POE vs EPE: Practical Comparison
| Parameter | EVA | POE | EPE |
|---|---|---|---|
| Industry maturity | Very high | High and growing | Growing |
| Moisture resistance | Moderate | Generally high | Generally improved |
| Electrical insulation | Good | Very good | Very good |
| PID considerations | Formulation dependent | Often advantageous | Often advantageous |
| Processing familiarity | Very high | Requires process control | Requires process control |
| Typical application | Broad PV applications | Advanced module technologies | Hybrid constructions |
This is a general technical comparison. It should not be interpreted as an Indian regulatory ranking or a statement that one material is universally superior.
Optical Properties of Solar Encapsulants
Because the encapsulant is located between the front glass and solar cells, its optical properties can directly influence light transmission to the cell.
Important parameters can include:
- Optical transmittance
- Solar-weighted photon transmittance
- Yellowness index
- UV cut-off wavelength
- Optical durability
Long-term optical stability is important because degradation of the encapsulant can increase optical losses.
Electrical Properties of Encapsulants
The encapsulant also acts as an electrical insulation layer within the module.
Important electrical considerations include:
- Volume resistivity
- Insulation performance
- Electrical stability
- Interaction with cell and interconnection structures
Appropriate electrical properties are important for both module safety and long-term reliability.
Thermal Properties and Dimensional Stability
PV modules experience repeated temperature changes throughout their operating life.
Encapsulants therefore need to maintain suitable properties during thermal exposure.
Important considerations include:
- Thermal stability
- Dimensional stability
- Thermal ageing
- Lamination behaviour
- Mechanical behaviour after thermal exposure
Moisture Resistance of PV Encapsulants
Moisture is one of the major environmental stresses affecting photovoltaic modules.
Moisture can contribute to degradation of:
- Cell metallization
- Interconnections
- Encapsulant interfaces
- Backsheet materials
- Adhesive interfaces
- Electrical components
POE is often selected when low moisture permeability is an important module-design requirement.
However: Low moisture permeability of the encapsulant alone does not guarantee overall module reliability. The complete module construction and manufacturing process must be considered.
Encapsulants and Potential-Induced Degradation (PID)
Potential-induced degradation, commonly known as PID, is an important PV reliability concern.
PID behaviour can depend on multiple factors, including:
- Cell technology
- System voltage
- Module construction
- Glass characteristics
- Encapsulant properties
- Temperature
- Humidity
POE-based encapsulation is often considered in module designs targeting improved resistance to certain PID mechanisms.
However, PID performance should be demonstrated through appropriate module-level qualification rather than assumed solely from the encapsulant type.
Encapsulant Selection for TOPCon Modules
TOPCon has become one of the major n-type photovoltaic technologies.
Encapsulant selection for TOPCon modules should consider:
- PID performance
- Moisture behaviour
- Adhesion
- Cell metallization compatibility
- Lamination window
- UV stability
- Electrical insulation
- Long-term reliability
The encapsulant should therefore be selected as part of the complete TOPCon module design.
Encapsulant Selection for HJT Modules
Heterojunction (HJT) modules can have different process and reliability considerations because of their cell structure and manufacturing approach.
Important encapsulant considerations include:
- Thermal-process compatibility
- Adhesion
- Optical performance
- Electrical insulation
- Cell and interconnect compatibility
- Long-term durability
What Should IQC Check for Solar Encapsulant?
From a manufacturing QA/QC perspective, encapsulant control should begin at Incoming Quality Control (IQC).
Material Identification
- Supplier
- Material grade
- Lot number
- Manufacturing date
- Shelf life
Dimensional Checks
- Thickness
- Width
- Length
- Thickness uniformity
Visual Inspection
- Foreign particles
- Wrinkles
- Bubbles
- Surface contamination
- Colour variation
- Physical damage
Documentation
- Certificate of Analysis
- Certificate of Conformity
- Batch traceability
- Supplier test report
The exact acceptance criteria should be defined in the manufacturer's approved material specification.
Why Encapsulant Thickness Control Matters
Encapsulant thickness is an important manufacturing parameter.
Variation in thickness can influence:
- Cell protection
- Lamination quality
- Adhesion
- Electrical insulation
- Module appearance
- Mechanical stress
Thickness should therefore be controlled as a process and quality parameter rather than treated only as a dimensional specification.
Why Lamination Process Control Is Critical
A high-quality encapsulant can still produce poor module performance if the lamination process is not properly controlled.
Important lamination parameters can include:
- Temperature
- Vacuum
- Pressure
- Cycle time
- Heating rate
- Cooling conditions
- Crosslinking behaviour
The appropriate process window depends on the encapsulant formulation and the complete module construction.
Changing from EVA to POE or EPE should not be treated as a simple material substitution. Process validation and appropriate qualification should be considered.
Encapsulant Material Qualification vs Module Qualification
These are two different quality activities.
Material Qualification
The encapsulant itself is evaluated for relevant physical, optical, electrical, thermal and durability properties.
Module Qualification
The encapsulant is evaluated as part of the complete module construction.
This distinction is critical because the interaction between the encapsulant and other module materials can influence long-term performance.
Final module reliability belongs to the complete module system—not to the encapsulant alone.
What Happens If the Encapsulant Is Changed?
A change in encapsulant can affect the manufacturing process and module performance.
Changes may include:
- Supplier change
- Material-grade change
- EVA to POE conversion
- POE to EPE conversion
- Encapsulant thickness change
- Encapsulant formulation change
Potential impacts include:
- Lamination recipe
- Adhesion
- Crosslinking
- Optical performance
- Electrical insulation
- PID performance
- Moisture behaviour
- Reliability-test results
Therefore, significant encapsulant changes should be managed through an appropriate engineering change and qualification process.
Does ALMM Specify Encapsulant Chemistry?
The Approved List of Models and Manufacturers (ALMM) is an important part of India's solar policy framework.
However, the current MNRE ALMM framework is focused on approved PV module models and manufacturers and, since 2025, approved PV cells.
The current ALMM information reviewed for this article does not establish a blanket requirement that PV manufacturers must use EVA, POE or EPE.
ALMM compliance should therefore not be interpreted as an encapsulant-specific material mandate.
Is EVA Banned in India?
No general ban on EVA for PV modules has been identified in the current Indian regulatory information reviewed for this article.
Likewise, the current framework reviewed does not establish a blanket requirement for manufacturers to replace EVA with POE.
Is POE Mandatory in India?
No blanket requirement mandating POE for all photovoltaic modules has been identified.
POE may be selected when its properties are appropriate for the module design and when the finished module meets the applicable qualification and compliance requirements.
What Should Indian PV Manufacturers Do in 2026?
Manufacturers should focus on technical qualification, standards compliance and process control rather than waiting for a chemistry-specific mandate.
1. Identify Applicable Standards
Maintain the latest applicable BIS and IEC requirements for the module design and certification pathway.
2. Qualify the Supplier
Evaluate supplier capability, consistency, documentation and material traceability.
3. Approve the Exact Material Grade
Material approval should be based on the specific material grade and approved specification rather than only the supplier name.
4. Establish IQC Requirements
Define incoming inspection parameters, sampling plans and acceptance criteria.
5. Validate the Lamination Process
Establish the appropriate lamination window for the selected encapsulant and module design.
6. Validate the Complete Module
Confirm that the encapsulant performs correctly within the complete module construction.
7. Conduct Reliability Testing
Apply the relevant module qualification and reliability testing requirements.
8. Control Material Changes
Significant changes should be managed through engineering change control and appropriate requalification.
Recommended Encapsulant Quality-Control Flow
Key Takeaway for QA/QC Engineers
Do not manage solar encapsulant only as an incoming raw material. Manage it as a critical PV-module reliability component.
A strong encapsulant control system connects:
IQC → Process Control → Lamination → Module Testing → Reliability → Field Feedback
This approach provides stronger quality control than simply checking the thickness and appearance of incoming encapsulant rolls.
Is POE Better Than EVA?
There is no universal answer.
The correct question is:
Which encapsulant is better for the specific module technology, environment, manufacturing process and reliability target?
POE can offer advantages in moisture resistance and certain PID-related applications. EVA offers extensive industry experience and mature processing. EPE can provide a hybrid approach.
The selection should consider:
- Cell technology
- Module architecture
- Operating environment
- Reliability requirements
- Lamination process
- Material availability
- Cost
Does a Better Encapsulant Automatically Mean a Better Module?
No.
A PV module is a complete system.
Its reliability depends on the interaction between:
- Solar cells
- Metallization
- Ribbons
- Solder/interconnection
- Encapsulant
- Glass
- Backsheet
- Sealants
- Junction box
- Lamination process
A premium encapsulant cannot compensate for poor process control elsewhere in the module.
Frequently Asked Questions
Is EVA banned in India for solar modules?
No general ban on EVA for PV modules has been identified in the current Indian regulatory information reviewed for this article.
Is POE mandatory for solar modules in India?
No blanket requirement mandating POE for all PV modules has been identified.
Can manufacturers use EPE encapsulant?
Encapsulant selection is based on the approved module design, applicable requirements, qualification and performance. A blanket EPE mandate has not been identified.
Does ALMM specify EVA or POE?
The current ALMM framework reviewed here does not establish a blanket requirement specifying EVA, POE or EPE chemistry.
Is encapsulant covered by IS/IEC 61730?
Yes. BIS records for IS/IEC 61730:2023 include encapsulant-related requirements under PV-module construction.
What should IQC check for encapsulant?
Depending on the approved specification, IQC can include material identity, lot traceability, dimensions, appearance, supplier documentation and relevant material-property checks.
Is POE always better than EVA?
No. The correct encapsulant depends on the cell technology, module construction, environment, manufacturing process and reliability requirements.
Why is encapsulant important for TOPCon and HJT?
Advanced n-type module technologies can have specific electrical, moisture, optical, thermal and reliability considerations, making encapsulant selection and qualification particularly important.
Conclusion
India's solar industry does not currently appear to have a blanket 2026 MNRE rule requiring PV manufacturers to use a particular encapsulant chemistry such as EVA, POE or EPE.
However, this does not mean encapsulant requirements are unimportant.
Encapsulants are part of the PV-module construction and safety framework, and BIS's current records for IS/IEC 61730:2023 include encapsulant-related requirements.
For manufacturers, the correct approach is therefore not simply to ask:
“EVA or POE—which one is legally required?”
The better question is:
“Which encapsulant is technically qualified for our module design and capable of meeting the applicable Indian, BIS and IEC requirements?”
As India moves toward higher-efficiency TOPCon, HJT and other advanced PV technologies, encapsulant selection, qualification, lamination control and reliability validation will become increasingly important.
The future of encapsulant management is therefore likely to be driven less by a single mandated chemistry and more by performance, reliability, qualification, traceability and module-level compliance.
