The rise of modern photovoltaics : Fundamental aspects of photovoltaic conversion

With photovoltaics, mankind gained access for the first time to a means of producing electrical energy that did not involve rotating parts and the steam thermal cycle. This was made possible by the discovery of the semi-conducting properties of certain materials, such as silicon, and of p-n junction-based devices - photovoltaic cells - enabling photon energy to be converted directly into electricity. We'll review the theories of solid-state physics and quantum physics that explain how cells work, and the main photovoltaic characteristics that result (creation of photocurrent and photovoltage). Theoretical maximum efficiencies will be presented, ranging from 33% for a single junction to almost 85% for devices such as multi-junctions and new concepts that are the subject of much research. These will be compared with the characteristics of current devices.