Third-generation photovoltaic cell

Third-generation photovoltaic cells are solar cells that are potentially able to overcome the Shockley–Queisser limit of 31–41% power efficiency for single bandgap solar cells. This includes a range of alternatives to cells made of semiconducting p-n junctions ("first generation") and thin film cells ("second generation"). Common third-generation systems include multi-layer ("tandem") cells made of amorphous silicon or gallium arsenide, while more theoretical developments include frequency conversion, (i.e. changing the frequencies of light that the cell cannot use to light frequencies that the cell can use - thus producing more power), hot-carrier effects and other multiple-carrier ejection techniques. Emerging photovoltaics include: Copper zinc tin sulfide solar cell (CZTS), and derivates CZTSe and CZTSSe Dye-sensitized solar cell, also known as "Grätzel cell" Organic solar cell Perovskite solar cell Quantum dot solar cell The achievements in the research of perovskite cells, especially, have received tremendous attention in the public as their research efficiencies recently soared above 20 percent. They also offer a wide spectrum of low-cost applications. In addition, another emerging technology, concentrator photovoltaics (CPV), uses high-efficient, multi-junction solar cells in combination with optical lenses and a tracking system. Solar cells can be thought of as visible light counterparts to radio receivers. A receiver consists of three basic parts; an antenna that converts the radio waves (light) into wave-like motions of electrons in the antenna material, an electronic valve that traps the electrons as they pop off the end of the antenna, and a tuner that amplifies electrons of a selected frequency. It is possible to build a solar cell identical to a radio, a system known as an optical rectenna, but to date these have not been practical. The majority of the solar electric market is made up of silicon-based devices. In silicon cells, the silicon acts as both the antenna (or electron donor, technically) as well as the electron valve.