
A new heat engine with no moving parts has been developed by engineers at MIT and the National Renewable Energy Laboratory (NREL) with a performance better than that of traditional steam turbines.
This heat engine, called a thermophotovoltaic (TPV) cell, can convert heat to electricity with over 40 percent efficiency, which is higher than the 35 percent efficiency achieved by steam turbines.
This technology could be incorporated into grid-scale thermal batteries that would store excess energy from renewable sources such as the sun.
The TPV cell is a promising development for a fully decarbonized power grid, supplied entirely by renewable energy.
What is a thermophotovoltaic cell?
Thermophotovoltaic (TPV) cells are two-junction devices that convert heat to electricity via photons and are made up of III–V materials with bandgaps between 1.0 and 1.4 eV.
A basic TPV system consists of a thermal source, a TPV cell, and a heat sink.
The thermal source can be generated from a variety of sources such as combustion of fuels, industrial waste heat, concentrated solar or nuclear energy, and emits predominantly infrared light at temperatures of 600°C or more.
The TPV cell captures the energy radiated as infrared light and converts it to electricity at high efficiency using semiconducting materials.
Solar Thermophotovoltaics (STPVs) are solar-driven heat engines that extract electrical power from thermal radiation by absorbing and converting solar radiation to heat and then using the TPV cell to convert the heat to electricity. The potential of thermophotovoltaics is promising as it offers a direct conversion process from heat to electricity with high efficiency.
Read more > A new heat engine with no moving parts is as efficient as a steam turbine