Skip to content
The methodOpen data
Back to the collection

Thermophotovoltaic efficiency of 40%

Alina LaPotin, Kevin L. Schulte, Myles A. Steiner

Show all 13 authors

Kyle Buznitsky, Colin C. Kelsall, Daniel J. Friedman, Eric J. Tervo, Ryan M. France, Michelle R. Young, Andrew Rohskopf, Shomik Verma, Evelyn N. Wang, Asegun Henry

2022 · Nature

Biology & medicine
Read the paper
HN score
0
Mentions
4
Readers
3
Months
4
What’s in a score?

From the abstract

Abstract Thermophotovoltaics (TPVs) convert predominantly infrared wavelength light to electricity via the photovoltaic effect, and can enable approaches to energy storage 1,2 and conversion 3–9 that use higher temperature heat sources than the turbines that are ubiquitous in electricity production today. Since the first demonstration of 29% efficient TPVs (Fig. 1a) using an integrated back surface reflector and a tungsten emitter at 2,000 °C (ref. 10 ), TPV fabrication and performance have improved 11,12 . However, despite predictions that TPV efficiencies can exceed 50% (refs. 11,13,14 ), the demonstrated efficiencies are still only as high as 32%, albeit at much lower temperatures below 1,300 °C (refs. 13–15 ). Here we report the fabrication and measurement of TPV cells with efficiencies of more than 40% and experimentally demonstrate the efficiency of high-bandgap tandem TPV cells. The TPV cells are two-junction devices comprising III–V materials with bandgaps between 1.0 and 1.4 eV that are optimized for emitter temperatures of 1,900–2,400 °C. The cells exploit the concept of band-edge spectral filtering to obtain high efficiency, using highly reflective back surface reflectors to reject unusable sub-bandgap radiation back to the emitter. A 1.4/1.2 eV device reached a maximum efficiency of (41.1 ± 1)% operating at a power density of 2.39 W cm –2 and an emitter temperature of 2,400 °C. A 1.2/1.0 eV device reached a maximum efficiency of (39.3 ± 1)% operating at a power density of 1.8 W cm –2 and an emitter temperature of 2,127 °C. These cells can be integrated into a TPV system for thermal energy grid storage to enable dispatchable renewable energy. This creates a pathway for thermal energy grid storage to reach sufficiently high efficiency and sufficiently low cost to enable decarbonization of the electricity grid.

Metadata: Crossref. Abstracts retain their original authors’ rights.

In the conversation

Original HN comments, with labels from simple text rules. A label describes the whole comment and may miss context or irony. Read the discussion to make up your own mind. About the labels

4 selected excerpts · 4 total mentions

westurner
Neutral mention · rule
> all power sources rely on taking cold water and making it warm constantly so that it makes a turbine move. PV (photovoltaic), TPV (thermopohotovoltaic), and thin film and other solid-state thermoelectric (TE) approaches do not rely upon corrosive water turning a turbine. Turbine blades can be made of materials that are more resistant to corrosion. On turbine efficiency: "How the gas turbine conquered the electric power industry" https://news.ycombinator.com/context?id=38314774 It looks like the GE 7HA gas/hydrogen turbine is still the most efficient turbine? https://gasturbineworld.com/ge-7ha-03-gas-turbine/ : > Higher efficiency: 43.3% in simple cycle and up to 64% in…
Read the full comment
combined cycle, Steam turbines aren't as efficient as gas turbines FWIU. /? which nuclear reactors do not have a steam turbine: "How can nuclear reactors work without steam?" [in space] https://www.reddit.com/r/askscience/comments/7ojhr8/how_can_... : > 5% efficient; you usually get less than 5% of the thermal energy converted into electricity (International space law prohibits putting nuclear reactors in space without specific international approval, which is considered for e.g. deep space probes like Voyager; though the sun is exempt.) Rankine cycle (steam) https://en.wikipedia.org/wiki/Rankine_cycle Thermoelectric effect: https://en.wikipedia.org/wiki/Thermoelectric_effect : > The term "thermoelectric effect" encompasses three separately identified effects: the Seebeck effect (temperature differences cause electromotive forces), the Peltier effect (thermocouples create temperature differences), and the Thomson effect (the Seebeck coefficient varies with temperature). "Thermophotovoltaic efficiency of 40%" https://www.nature.com/articles/s41586-022-04473-y Multi-junction PV cells are not limited by the Shockley–Queisser limit, but are limited by current production methods. Multi-junction solar cells: https://en.wikipedia.org/wiki/Multi-junction_solar_cell#Mult... Which existing thermoelectric or thermopohotovoltaic approaches work with nuclear fusion levels of heat (infrared)?
Original comment Nuclear fusion: WEST beats the world record for plasma duration
perihelions
Neutral mention · rule
You won't get the claimed efficiency that way: it only applies to an enclosed heat source. It's critical that they're reflecting light outside of the PV bandgap back into the thermal mass, where it's re-absorbed and re-emitted again. If you try that with solar radiation, you'll lose most of it back into the sky. https://www.nature.com/articles/s41586-022-04473-y.pdf (Equation 1 and surrounding discussion, and the energy-flow diagrams in Figure 1).
Original comment US startup begins producing 40%-efficient thermophotovoltaic cells
westurner
Neutral mention · rule
https://news.ycombinator.com/item?id=33431427 : > FWIU, heat engines are useful with all thermal gradients: pipes, engines, probably solar panels and attics; "MIT’s new heat engine beats a steam turbine in efficiency" (2022) https://www.freethink.com/environment/heat-engine "Thermophotovoltaic efficiency of 40%" (2022) https://www.nature.com/articles/s41586-022-04473-y https://scholar.google.com/scholar?cites=1419736444024563175... "Capturing Light From Heat at 40% Efficiency, NREL Makes Big Strides in Thermophotovoltaics" (2022) https://www.nrel.gov/news/program/2022/capturing-light-from-.... : > The 41%-efficient TPV device is a tandem cell—a photovoltaic device…
Read the full comment
built out of two light-absorbing layers stacked on top of each other and each optimized to absorb slightly different wavelengths of light. The team achieved this record efficiency through the usage of high-performance cells optimized to absorb higher-energy infrared light when compared to past TPV designs. This design builds on previous work from the NREL team. > Another crucial design feature leading to the high efficiency is a highly reflective gold mirror at the back of the cell. Much of the emitted infrared light has a longer (less energetic) wavelength than what the cell's active layers can absorb. This back surface reflector bounces 93% of that unabsorbed light back to the emitter, where it is reabsorbed and reemitted, improving the overall efficiency of the system. Further improvements to the reflectance of the back reflector could drive future TPV efficiencies close to or above 50%. Thermoelectric effect: https://en.wikipedia.org/wiki/Thermoelectric_effect Thermophotovoltaic energy conversion *: https://en.wikipedia.org/wiki/Thermophotovoltaic_energy_conv... Thermophotonics: https://en.wikipedia.org/wiki/Thermophotonics Gas turbine: https://en.wikipedia.org/wiki/Gas_turbine : > gross thermal efficiency exceeds 60%. [100] (2011) GE-7HA https://www.ge.com/news/press-releases/ha-technology-now-ava... (2017) : > that its largest and most efficient gas turbine, the HA, is now available at more than 64 percent efficiency in combined cycle power plants, higher than any other competing technology today. How do TPV operating and lifecycle costs differ from gas turbine's costs?
Original comment How the Gas Turbine Conquered the Electric Power Industry

Keep following the thread.

More in Biology & medicine

More from the same topics.