The development of solar cells has experienced three stages over the past 50 years, from monocrystalline silicon to polycrystalline silicon and thin film solar cells. The solar cells in each generation have different technical specifications and are more widely used in different application fields. Let’s take a look at the different generations of solar cells and their solar energy conversion efficiency.

First Generation Solar Cells
The first generation of solar cells, also known as traditional solar cells, are made from silicon wafers. They were the first type of solar cell to be mass-produced and used in renewable energy sources. These types of solar cells use semiconductors which convert sunlight into electricity with a low efficiency rate. It is the most expensive form of renewable energy because it takes more materials and manufacturing costs than other forms.

Second Generation Thin Film
Second generation solar cells are made from thin film materials. They have a higher solar energy conversion efficiency than first generation cells, making them a more renewable energy source. They are also less expensive to manufacture. Second generation solar cells are made from materials such as cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and amorphous silicon (a-Si). These three types of second-generation solar cells are the most popular on the market today. The manufacturing process for these types is cheaper because it doesn’t require semiconductors or crystalline silicon wafers.

Third Generation Multi-junction
Multi-junction solar cells are the most efficient type of solar cell available, with an efficiency of up to 40%. They are made from materials such as gallium arsenide and indium phosphide, which are layered on top of each other to create a junction. Multi-junction solar cells are more expensive than other types of solar cells, but they are also able to convert more sunlight into renewable energy. The efficiency is measured in terms of watts per square meter. Higher numbers indicate higher efficiencies and lower costs per kilowatt hour (kWh). For example, at 50% efficiency, it would take 1000 hours to produce enough electricity for one kWh. In contrast, at 30% efficiency, it would take 30 hours to produce one kWh.

Fourth Generation Concentrating Photovoltaics
These are the latest generation of solar cells and they are still in development. They use renewable energy sources like solar thermal to generate electricity. They are more efficient than first generation solar cells, but they are also more expensive. Scientists predict that these will be the next most used type of solar cell by 2030 because they can harness even more energy from sunlight.

Fifth Generation – Quantum dot nanocrystals (QDNC)
QDNCs are made of semiconductor nanocrystals that are just a few atoms in size. They have unique electronic properties that make them ideal for solar energy conversion. QDNCs can be tuned to absorb specific wavelengths of light, which means they can be used to create more efficient solar cells. Additionally, QDNCs are more stable than other types of solar cells, meaning they can last longer and be used more effectively. The downside is that manufacturing these materials is difficult, expensive, and time-consuming. Therefore, this type of solar cell has not been widely adopted by the industry yet.