Photovoltaic energy that works at night is possible with the thermoradiative diode


Editor of the Technological Innovation site – 05/19/2022

The conversion of infrared radiation into electricity opens up the field of nocturnal solar energy.
[Imagem: UNSW Sydney]

Convert infrared to electricity

The Sun significantly heats the Earth’s crust during the day; but it only needs to settle down for this energy to be quickly lost in the cold of space.

Now researchers in Australia have successfully tested what they call a “thermoradiative diode”, a component capable of converting that heat into electrical energy.

This, according to the team, ushers in “nighttime solar power” in practice. In fact, the energy was provided by the Sun and the term photovoltaic refers to the transformation of photons into currents of electrons – the only difference is that in this case the photons are in the infrared range and not in the visible area.

Professor Nicholas Daukes, from the University of New South Wales, explains the research: “In the late 18th and early 19th centuries it was discovered that the efficiency of steam engines depended on the difference in temperature in the engine, and this is how the field of thermodynamics was born.

The same principles apply solar energy – the Sun provides the hot source and a relatively cold solar panel on the Earth’s surface provides a cold absorber. This makes it possible to produce electricity.

“However, when we think of Earth’s infrared emission in outer space, Earth is now the relatively warm body, with the vast vacuum of space being extremely cold.

“By the same principles of thermodynamics, it is also possible to generate electricity from this temperature difference: the emission of infrared light into space.”

“We usually think of the emission of light as something that consumes energy, but in the mid-infrared, where we all shine with radiant energy, we show that it is possible to extract energy electric.”

The thermoradiative diode paves the way for working photovoltaics

Component structure, which now needs to improve its efficiency.
[Imagem: Michael P. Nielsen et al. – 10.1021/acsphotonics.2c00223]

Photovoltaic that works at night

The amount of energy produced by the thermoradiative diode built by the team is small, about 0.001% of the electricity produced by a solar cell, but the proof of concept is important because the amount of thermal energy available is immense.

“We still don’t have the magic bullet that will make the thermoradiative diode an everyday reality, but we’ve done a proof-of-principle and are excited to see how much better we can improve on that in the years to come,” says Nicholas.

The team is already entering the next phase of the research, which will focus on finding more efficient materials to build optimized versions of the infrared energy-to-electricity converter.

And they are not alone: ​​this area emerging from a photovoltaic that works at night already has teams from different parts of the world.


Article: Thermoradiative power conversion from HgCdtTe photodiodes and their current-voltage characteristics
Authors: Michael P. Nielsen, Andreas Pusch, Muhammad H. Sazzad, Phoebe M. Pearce, Peter J. Reece, Nicholas J. Ekins-Daukes
Magazine: ACS Photonics
DOI: 10.1021/acsphotonics.2c00223

Follow the technological innovation site on Google News

Other news about:

more topics

Leave a Comment