Dear Jane Bruneau

Efficiency of solar cells are strongly depend on material type and its properties. For each materials, there is Shovkley-QUisser limit which shows theoretical highes efficiency. For example, if you create solar cell from silicon, you cannot overcome 29% efficiency. If you create silicon solar cell from only silicon, you can get 12-16% efficiency. Now, in experiment, efficiency of silicon solar cells is about 24%. Silicon solar cell is optimised to reach 24% from 12%: antireflection coatings, textures, optimal contacts, light trapping structures, optiam doping concentrations and so on.

I think that now solar cell reached to its efficiency limit, we cannot increase its efficiency just changing geomtric structurture. I think that this is main reason that all reputable scientists jump to nanostructured solar cells and finding new materials.

Jasurbek Gulomov

Improving the efficiency of solar cells is a key focus in renewable energy research. Here are some effective strategies: Use High-Efficiency Materials: Materials like perovskites and tandem cells (combining different materials) have shown significant efficiency improvements.

Multi-Junction Cells: Combining different layers of existing materials to create multi-junction cells can capture a broader spectrum of sunlight, thereby improving efficiency. Improved Charge Carrier Collection: Enhancing the collection of charge carriers (electrons and holes) by optimizing the design of the cell’s contacts and using better conductive materials can reduce losses. Thermal Management: Implementing effective thermal management systems to dissipate heat can prevent efficiency losses due to overheating1. Organic Solar Cells: Exploring organic solar cells, which use carbon-based materials, can offer a flexible and potentially lower-cost alternative to traditional semiconductors. Concentrated Solar Power (CSP): Using lenses or mirrors to concentrate sunlight onto a smaller, high-efficiency solar cell can significantly boost overall system efficiency.

The Schottky-Queisser (that's how it is spelled, I think) limit refers to a single material with a given band-gap. The optimal band-gap for a single material under standard sunlight illumination would be just under 1.5eV, however, with multiple materials of different band-gaps you can improve on the Schottky-Queisser limit. That's the reason for multiple junction solar cells.