In addition to the perfect mainstream technology, many new technologies have emerged. Some technologies are based on existing knowledge and research, and some technologies need to be coordinated with new materials and new technologies.
①Dye-sensitized solar cell
The technology of dye-sensitized solar cells is still immature. At the atomic level, this type of battery works very differently from other solar cells and does not use silicon. Dye-sensitized solar cells use titanium dioxide (also used in toothpaste) and colored dyes, and their manufacturing costs are much lower than other solar cells, and they work better under low light conditions. Dye-sensitized solar cells are transparent and can be made into many different colors, making them ideal materials for building materials such as glass. Dye-sensitized solar cells have the potential for military applications because they can be made into camouflage patterns.
Currently, the highest laboratory efficiency of dye-sensitized solar cells is 12%, and the cell efficiency of mass production is 7%.
The silver-containing battery was developed by the Australian National University and is a very thin monocrystalline silicon solar cell. It is a double-sided battery (both sides can absorb light), which makes it a unique silicon battery. The efficiency of the silver-containing battery has reached more than 19%, and the module efficiency is 13.8%. This kind of battery is in the early stage of commercialization, but it has shown the potential in the application of photovoltaic building integration.
③Heterojunction (HIT) photovoltaic cell with intrinsic thin layer
HIT modules use both crystalline silicon solar cells and amorphous silicon thin film cells, and achieve a module efficiency of 17% and a cell efficiency of 22%
④I-V group semiconductor
Group III-V solar cells or extrinsic semiconductor solar cells use a group III element and a group V element in the periodic table (silicon is a group IV element), such as arsenic, which is usually used as a space solar cell Gallium battery. This type of solar cell is generally a multi-junction cell, in fact a multilayer solar cell, which can absorb different colors in visible light. This type of battery is also commonly used in advanced solar concentrating technology to increase the incident solar radiation. Multi-junction extrinsic semiconductor solar cells are the most efficient and most expensive solar cells on the market. The highest laboratory efficiency record is 41.6%, which was created by Spectrolab of the United States. Due to the high cost, III-V semiconductor batteries are usually used in space applications such as satellites, or solar-powered aircraft, solar-powered racing cars (see Figure 1) and other high-budget, high-performance solar-powered equipment.
⑤Solar concentrating technology
Solar concentrating technology is used to increase the intensity of incident light from solar cells, thereby generating more power (solar cells output concentrators, but the most commonly used concentrating method is lens or trough reflection.
Solar concentrating technology increases the output power of the battery, so its advantage is that it can reduce the number of batteries required by the system (generally, the cost of solar cells is the highest when the system is installed). As the battery operating temperature becomes very high, many batteries require a cooling system to improve performance. The challenge of this type of technology is to develop a sturdy and reliable concentrator that must survive decades of photovoltaic system operation, sometimes in harsh conditions such as deserts, and reduce costs as much as possible.