Thermophotovoltaic (TPV) systems are a type of energy conversion technology that generate electricity by utilizing thermal radiation emitted from a high-temperature heat source. These systems typically consist of three main components: a heat source, a thermal emitter, and photovoltaic cells.
Here's a basic explanation of how electricity is generated in thermophotovoltaic systems for terrestrial applications:
Heat Source: The first step in a TPV system is to provide a high-temperature heat source. This heat source can be obtained from various methods, such as burning fossil fuels (natural gas, propane, etc.), using concentrated solar power, or even waste heat from industrial processes.
Thermal Emitter: The heat generated from the heat source is then transferred to a thermal emitter. The thermal emitter's role is to absorb the heat and re-radiate it as thermal radiation, which includes photons with specific wavelengths.
Photovoltaic Cells: The thermal radiation emitted by the thermal emitter contains photons that strike the surface of photovoltaic cells. Photovoltaic cells are semiconductor devices that can convert light (photons) into electricity through the photovoltaic effect.
Electricity Generation: When the photons from the thermal radiation hit the photovoltaic cells, they excite electrons within the semiconductor material of the cells. This excitation creates an electric current, which is then collected and used as electricity.
It's worth noting that TPV systems have certain advantages and challenges. They have the potential to achieve high energy conversion efficiency since they can utilize a broad spectrum of thermal radiation, but they also face difficulties related to thermal losses and selecting appropriate materials that can handle the high operating temperatures.
In summary, TPV systems for terrestrial applications generate electricity by using a heat source to produce thermal radiation, which is then converted into electrical energy by photovoltaic cells via the photovoltaic effect.