Heterojunction (HJT) solar cell technology has emerged as a promising and relatively recent innovation in the field of solar cells, gaining significant traction in recent years due to its enhanced efficiency in converting sunlight into electricity.
Heterojunction solar panels are a specific type of photovoltaic panel characterized by a tri-layered structure, integrating two distinct technologies: crystalline silicon and amorphous “thin-film” silicon, synergistically optimizing electricity production.
HJT cells are composed of three key materials: Crystalline Silicon (c-Si), Amorphous Silicon (a-Si), and Indium Tin Oxide (ITO).
The initial layer, consisting of amorphous silicon, intercepts sunlight even before it reaches the crystalline layer, as well as any light that bounces off the underlying layers. The middle layer is composed of monocrystalline silicon, primarily responsible for converting the majority of sunlight into electricity. Finally, there is another amorphous thin-film silicon layer situated behind the crystalline silicon layer, capturing any remaining photons that have managed to penetrate the first two layers.
Through the harmonious combination of these two distinct technologies, heterojunction solar panels can harness more energy than either technology could achieve individually. These panels can achieve impressive efficiencies exceeding 25%, making them an increasingly attractive option for solar energy generation.
Advantages of HJT Solar Panels
- High Efficiency: HJT panels boast exceptional efficiency, reaching up to 30% for bifacial modules.
- Temperature Resilience: They perform well in high-temperature environments due to a favorable temperature coefficient.
- Bifacial Capability: HJT cells exhibit a high bifaciality factor of 92%, ideal for utility-scale projects.
- Stramlined Manufacturing: HJT modules require only 5-7 manufacturing steps, reducing production costs.
Disadvantages of HJT Solar Panels
- High Cost: HJT panels are pricier due to complex manufacturing and costly materials.
- Fragile Structure: Their thin, intricate design makes them susceptible to damage.
- Sensitivity to Moisture: HJT panels are moisture-sensitive, affecting efficiency and durability.
- Complex Production: Specialized equipment and expertise are needed for manufacturing.
- Limited Scale: Production is smaller, potentially increasing costs and limiting availability.
- New Technology: Installation and maintenance experience may be limited due to their recent introduction.
Uses of HJT Solar Cell
- Building Integration: HJT solar panels seamlessly blend into building facades, roofs, and windows, adding both aesthetic appeal and energy efficiency to structures.
- Compact Applications: In space-limited scenarios like portable solar chargers, off-grid cabins, and small boats, HJT solar panels excel due to their compact size and impressive efficiency.
- Utility-Scale Solar Farms: HJT panels find a valuable role in large-scale solar power plants, particularly in regions with abundant solar irradiance, enhancing overall efficiency for these expansive energy projects.