What is a half-cut cell
A half-cut cell module is a photovoltaic module whose cells have been laser-cut in half along their midline, doubling the cell count and halving the current flowing through each cell. The reduced per-cell current cuts I²R resistive losses in the interconnect ribbons and the junction box, raising module efficiency by 1 to 3 percent.
The architecture also enables dual-string interconnection inside the module: the top half forms one string and the bottom half forms another. When partial shading affects the lower row, only that string is curtailed, while the upper string continues at full output. Conventional full-cell modules with linear interconnection lose entire strings under any panel-edge shading.
Half-cut cell modules have become the default in Indian and global crystalline silicon solar from 2020 onward. Most modules on the current ALMM List Phase III in 2024 to 2026 are half-cut, with full-cell modules persisting only in legacy spare supply.
Half-cut explained simply
Take a standard solar cell. Slice it in half with a laser. You now have two cells where you had one, each producing half the current but the same voltage. Wire them together to make the same panel, and the lower current means less heating and less power loss.
Bonus: split the panel into top half and bottom half, with each half wired separately. If a shadow falls on the bottom row, only the bottom half loses output. The top keeps producing.
Why half-cut matters
Efficiency gain. 1 to 3 percent module efficiency uplift over equivalent full-cell.
Lower hot-spot temperature. Lower current means lower local heating under partial shading.
Better partial shade response. Dual-string architecture isolates shaded sections.
Standard at module level. Almost all new module manufacturing uses half-cut, and it works seamlessly with standard string inverters without any special MPPT configuration.
Minimal cost premium. Manufacturing additional cost is small, easily recovered in yield gain.
How half-cut cells work
- Full silicon cell is laser-cut along the midline.
- Two half-cells produced, each half the area of the original.
- Half-cells are interconnected in series.
- The top half of the module and the bottom half are wired as separate strings.
- Each half-string has its own bypass diode in the junction box.
- Under uniform illumination, both halves contribute equal power.
- Under partial shading, only the affected half is curtailed.
The voltage per cell is unchanged (defined by silicon physics, not area). The current per cell is halved. Module voltage is unchanged. Module current is halved (split between top and bottom strings).
Technical deep dive
Loss reduction
I²R losses in the interconnect ribbons:
Halving I quarters the loss. Across a 144 half-cell module, the ribbon and busbar resistance losses drop by 60 to 75 percent.
Junction box architecture
| Diode configuration | Notes |
|---|---|
| Three diodes | Standard, one per half-string of three sub-strings |
| Six diodes | Premium, six sub-strings, finer shade response |
Module form factor
A 144 half-cell module is roughly the same physical size as a 72 full-cell module. Wattage class typically 540 to 600 W for utility-grade bifacial half-cut TOPCon.
Combination with cell technology
Half-cut compatibility spans PERC, TOPCon and HJT alike:
| Cell tech | Half-cut form |
|---|---|
| PERC | Standard 144 half-cell PERC mono |
| TOPCon | 144 half-cell TOPCon mono |
| HJT | 132 or 144 half-cell HJT bifacial |
| Shingled | Further sub-division |
Manufacturing
- Standard cell production through doping and metallisation.
- Laser cutting of finished cells.
- Edge passivation (some processes) to prevent recombination at cut edges.
- Standard stringing, lamination and framing.
Real-world applications
Indian rooftop solar.
Utility-scale solar parks.
C&I solar.
Solar carports and ground-mount structures.
Floating solar.
PM-KUSUM solar pumping with rooftop.
Residential under PM Surya Ghar.
Advantages
Higher module efficiency.
Better partial shade tolerance.
Lower hot-spot temperatures.
Lower operational cell temperatures (slightly).
Minimal cost increase over full-cell.
Compatible with all major cell technologies.
Limitations
Slightly more complex manufacturing process.
More cell edges potentially susceptible to micro-cracks.
Negligible drawback in practice.
Common problems
Cut-edge micro-crack initiation in older or poorly-processed half-cells.
Shorter expected reliability versus full-cell in theory; mitigated by modern process control.
Bypass diode failure in junction box, same as full-cell modules.
Best practices
Specify half-cut as default for new installations.
Choose ALMM-listed manufacturers with track record.
Verify junction box quality and diode redundancy.
Use proper handling to avoid edge stress.
Document module electrical parameters at commissioning.
Comparison: half-cut vs full-cell
| Feature | Half-cut | Full-cell |
|---|---|---|
| Cell count | 120 or 144 | 60 or 72 |
| Current per cell | Half | Full |
| I²R loss | Quartered | Baseline |
| Module efficiency | +1 to 3% | Baseline |
| Hot spot temperature | Lower | Higher |
| Partial shade tolerance | Better | Worse |
| Cost premium | Minimal | Baseline |
Indian market context
Half-cut technology is standard in Indian ALMM-listed modules from 2020 onward. Major Indian manufacturers (Waaree, Adani Green Solar, Tata Power Solar, Vikram Solar, Goldi Solar) ship half-cut modules across PERC, TOPCon and HJT cell platforms.
PM Surya Ghar accepts half-cut ALMM-listed modules.
SECI utility tender bid documents typically assume half-cut.
Full-cell module shipments are largely for legacy replacement supply.
Standards and certifications
| Standard | Scope |
|---|---|
| IEC 61215 | Module qualification |
| IEC 61730 | Module safety |
| IS 14286 | Indian Standard for crystalline modules |
| MNRE ALMM | Listing for subsidies |
| BIS certification | Quality compliance |
Common mistakes
Choosing full-cell modules to save a small upfront cost without considering lifecycle yield.
Ignoring junction box diode configuration when selecting half-cut modules.
Mishandling at site, breaking cut-edge cells.
Mixing half-cut and full-cell in same string. (Same string voltage but different optimal MPP behaviour.)
Key takeaways
Half-cut cell modules are the default for Indian and global solar module manufacturing from 2020 onward. The 1 to 3 percent efficiency gain, better shade tolerance and lower hot-spot temperatures justify the architecture across PERC, TOPCon and HJT cell technologies. Minimal cost premium and broad ALMM availability make it the rational choice for any new installation.
Further reading
For how Half-Cut Cell plays out in real projects, these guides go deeper:
- Solar Shading Analysis Software 2026: Guide
- Best Solar System Under ₹1 Lakh in India 2026
- Solar Subsidy in Madhya Pradesh 2026, MPPKVVCL
- Solar Shading Analysis Software Singapore: 2026
Sources
- IEC 61215, Module qualification.
- IEC 61730-1, -2, Module safety.
- IS 14286, Indian Standard for crystalline silicon PV modules.
- MNRE Approved List of Models and Manufacturers (ALMM).
- ITRPV Roadmap, latest edition, VDMA.
- IEA PVPS Trends in Photovoltaic Applications 2024.
- Hanifi H., Schneider J., Bagdahn J., Loss analysis and optimization of PV module components, Energy Procedia, 2016.
- Manufacturer datasheets from Waaree, Adani Green Solar, Tata Power Solar, Vikram Solar, Goldi Solar.
- NREL PV Module Technologies Report.
Frequently Asked Questions
What is a half-cut cell in simple words?
Why does half-cutting cells improve efficiency?
How much extra efficiency does half-cut give?
Are half-cut modules more reliable?
How are half-cells made?
How many half-cells in a module?
Are half-cut modules bifacial?
Are half-cut modules ALMM-listed?
Do half-cut modules need special inverters?
How many bypass diodes in half-cut modules?
Does half-cut affect module size?
Are half-cut modules more fragile?
What is third-cut or shingled cell?
Does half-cut work with all cell technologies?
Should I prefer half-cut over full-cell?
From the Blog
Co-founder & CEO driving Qbits Energy's product strategy and growth across India.