Researchers Build Device That Turns Heat Into Light, Possibly Boosting Solar Cell Efficiency

Kant (Slashdot reader #67,320) shared this story from the photovoltaics news site PV Magazine: Scientists at Rice University in Texas have developed a device which converts heat into light by squeezing it into a smaller bandgap. The ‘hyperbolic thermal emitter’ could be combined with a PV system to convert energy otherwise wasted as heat — a development the researchers say could drastically increase efficiency… “Any hot surface emits light as thermal radiation,” said Gururaj Naik, assistant professor of electrical and computer engineering at Rice. “The problem is that thermal radiation is broadband while the conversion of light to electricity is efficient only if the emission is in a narrow band.” The team worked to create a device that could squeeze the photons emitted as heat into a narrower band that could be absorbed by a solar cell… The next step for the research will be to combine the ‘hyperbolic thermal emitter’ device with a solar cell. “By squeezing all the wasted thermal energy into a small spectral region we can turn it into electricity very efficiently,” said Naik, “the theoretical prediction is that we can get 80% efficiency.”