What are Multi-Junction Solar Cells?

university wafer substrates

Multi-Junction Solar Cell Research

Our group is focusing on the harvesting of solar energy underwater. We are looking for the supply of photovoltaic cells having a bandgap in the range of 1.8eV to 2.3eV in order to optimize solar energy. Preferably looking for Indium Gallium Phosphide, Gallium Arsenide. We would like to know if you have a product which can suffice our need? We would also like if we could get a quotation for same with delivery time.

We have a few follow-up questions about the products. First, As informed before, the application is for research work so the solar panel is required in a special shape which we will describe at a later stage. Secondly, The size of the panel, can you provide panels in different sizes? such as 10 sq.cm, 20 sq,cm, 30 sq.cm and 50 sq.cm. Thirdly, can you tell us the approximate power output of the TJ cells? Lastly, do you also make flexible panels? in the same configurations? Awaiting your response.

Click for answer: Or reference #257878 for specs/pricing.

Get Your Quote FAST! Or, buy online and start researching today!

Our Answer to harvesting of solar energy

We did literature study before preparing the offer. Because the testing and the final product water depth are different, two different kinds of panels, each one designed for a different depth of water, are advised to use. For shallow water the panel with TJ cells are recommended to use and for deeper water, the panel with DJ cells are recommended to use. Our offer is valid for DJ or TJ, price is the same for both.

Please check attached the water absorption spectrums from the different sources in the literature. Each has minor differences but generally limited by the 20m for IR radiation. Besides, the band gap (1.8eV to 2.3eV which is between 540nm to ~690nm) doesn’t match conventional TJ cells. Please also check out the band gap diagram from the attached figures. Germanium junction (band gap 0,7eV) will not produce so much and may cause more losses than what it brings. So, we recommend Dual junction made of GaAs/ (Al)GaInP which is best fitting to your requirements.

Additional notes: Usually sea water absorption spectrum may not allow Germanium junction to produce enough efficiency (<1%) due to IR absorption of the water surface (only Works in the dept less than a few meters). Therefore our offer also includes DJ which can also work almost without a significant change in the efficiency similarly to TJ. Since we don't know the power consumption and current requirements or AC/DC operation etc. of the customer module to be powered by the panels we prepared a standard generic solution. Please let us know if the customer has additional requirements like inverter etc. They can be subject to separate quotes from us.

Here are our answers:

Special shapes with the custom designed solar cells and panels are available, but please note that we are working with a full wafer process so any smaller shape SC than 3” or 4” will be also patterned on full wafer and then can be cut into special shapes according to customer requirements. So this would have the same cost as the full 3” or 4” Wafer process.

Yes, 10-20-30-50sq.cm solar cells are available.

Reg to flexible panels: We have no experience on flexible solar cells yet. I mean solar cells on fully flexible plastic substrates with different thin film materials rather than GaAs/Ge etc.

Flexible panels are possible at some point, I mean individual cells will be still rigid but they can be placed on a flexible carrier as solar cell array.  So it is partially flexible.

Typical power of the TJ cells is about >100mW/cm2.


What is a Multi-Junction Solar Cell?

A multi-junction solar cell is a type of solar cell that is made from multiple layers of semiconductor materials, multi-junction silicon solar celleach of which is designed to absorb light in a specific range of wavelengths. Multi-junction solar cells are able to absorb and convert a wider range of wavelengths than single junction solar cells, which makes them more efficient at converting sunlight into electricity.

Multi-junction solar cells are used in a variety of applications, including in space-based solar power systems and in concentrated photovoltaic (CPV) systems. They are also used in research and development for a variety of other applications, including in the development of new materials for use in a range of technologies.

Multi-junction solar cells are typically more expensive to manufacture than single junction solar cells, but they are able to achieve much higher conversion efficiencies, typically in the range of 30% to 40%. They are an important part of the global renewable energy industry and are used in a variety of applications around the world.

What are Multi-Junction Solar Cell Advantages and Disadvantages

Advantages of Multi-Junction Solar Cells:

High efficiency: Multi-junction solar cells are designed to capture a wider range of the solar spectrum, leading to higher conversion efficiencies compared to traditional single-junction solar cells.

Improved performance under high light intensity: The multiple layers of multi-junction cells can help to mitigate the effects of high light intensity, allowing for improved performance and stability.

Cost-effective in certain applications: For specific high-power applications, such as in space or concentrating photovoltaic systems, multi-junction cells can be cost-effective due to their high efficiency and improved performance.

Disadvantages of Multi-Junction Solar Cells:

Complex fabrication process: The fabrication process of multi-junction cells is complex and requires specialized equipment and techniques, which can drive up costs and limit scalability.

Fragility: The multiple layers of multi-junction cells can make them more fragile compared to traditional single-junction cells, which can limit their applicability in certain situations.

Higher cost: The higher efficiency and improved performance of multi-junction cells come at a higher cost compared to traditional single-junction cells, making them less cost-effective for certain applications.

Limited availability: Multi-junction cells are still relatively new technology and may not be widely available or easily accessible for all applications.

Multi-junction solar cells are a type of photovoltaic (PV) cell that consists of multiple p-n junctions. These cells are also sometimes called tandem cells, as they stack multiple cells on top of one another.

Each p-n junction is made of different materials, with each junction optimized for absorbing a different portion of the solar spectrum. By stacking these junctions together, multi-junction cells can achieve higher efficiencies compared to traditional solar cells.

In a typical solar cell, photons from the sun are absorbed by the semiconductor material in the cell, creating electron-hole pairs. These charges are then separated by an electric field within the cell, producing a current. However, not all photons have enough energy to create electron-hole pairs in a single-junction cell, and any excess energy in high-energy photons is wasted as heat.

Multi-junction cells address this problem by using a combination of materials to capture a wider range of the solar spectrum. Each material is designed to capture a different range of photons, allowing the cell to convert a greater portion of the incoming sunlight into electricity. The stacked junctions also capture the excess energy in high-energy photons, increasing the efficiency of the cell.

Multi-junction solar cells are commonly used in space applications, where their high efficiency and lightweight construction make them an ideal choice. They are also being developed for terrestrial use, although their high cost remains a challenge for widespread adoption in commercial solar applications.