Cody -
That would be good for a concentrated solar array. Do you have any idea how it works?
https://ui.adsabs.harvard.edu/abs/2019JPhD...52A5501O/abstract
I always wondered if (when) someone would achieve this... as the article alludes, the effect is similar to the visible-spectrum PV we are familiar with, but in a much different spectrum (related to a 1900-2400C black-body). TPVs in the near-infrared are not new but the energy density isn't as nearly as high and I think primarily used in very niche applications. https://en.wikipedia.org/wiki/Thermophotovoltaic
You are probably already familiar with Thermocouples, Thermo Electric Generators (TEG) and heat/cool solid state devices based on the Seebeck or Peltier (respectively) effects. The TEG effect is less sensitive to temperature *range* and depends only on a temperature *gradient* and is related to differential movement of charge-carriers in different metals. These have very low efficiencies as well as most sources being intrinsically low-energy density. Common examples are 12V coolers and woodstove fans where convenience outweighs low efficiency. https://en.wikipedia.org/wiki/Thermoelectric_effect
There is also a technology known as Thermo Photonic Generation (TPX) which has an extra level of indirection... with a *biased* LED exposed to thermal radiation re-emitting the energy at a frequency that can be used by a more conventional PV cell. https://en.wikipedia.org/wiki/Thermophotonics
There is a (roughly) 6 meter diameter solar collector near my house (on Pojoaque Pueblo land) that was part of a proof-of-concept project spinoff from LANL for concentrated solar *hydrogen* conversion... I don't remember what temperatures they were achieving at the focal point, but the "generator" on an articulating boom is probabl .5x1.5 M across with a quartz? window and well-insulated tubes coming in/out. As I understand it, the hydrogen-generation was effected with/through high-temperature steam. I don't know if the working fluid is steam or something less corrosive. 15 years abandoned, it is now quite defunct with individual mirror segments (.5mx.5m) dangling from their bases.
An obvious problem with these very high temperature systems is that common materials tend to be mechanically (melting) and/or chemically (oxidizing, etc).
I don't know the practical limits on *linear* solar concentrators, but with the sun offering up approximately 1000W/m^2 one can likely reach the temperatures for this new device without the complications of 2D parabolics.
As a neo-retro (mostly) low-tech DIY guy, I am a fan of low-grade energy sources.
It won't surprise you that I have 2 huge front-surface mirrors just waiting for someone to put them to a good use. they are roughly 1.5mx2.1m (5'x7') and are optical grade (not that this matters) aluminized mylar stretched over a frame which happens to be closed on the back. There are pressure-equalization holes (valves) in the frame but in principle one could close them up and draw a vacuum and get a very shallow concave (catenary?) shape. They only weigh about 10-15kg and I could even deliver! I could probably throw in a 3x5 fresnel lens if you want to make a sand-fusing 3D printer or solar forge in your backyard? They would also be useful in a dance studio or (narcissistic) gym environment. Free for the taking (including delivery).
FWIW I tried to contritely use only CGS/SI units here... but I continue to reserve the right, no matter the units, to take advantage of the intuitively (and mechanically) convenient fractional arithmetic that comes with folding or separating things into halves, thirds, etc as well as working with 3/4/5 triangles. I grew up *just* before calculators and computers were common and did learn a slide-rule and acknowledge that slide rules do not have fractional inch measures on them. I once had a roughly 1.5 meter one (from a classroom) and one probably no longer than 10-15cm in length (yes, I have to calculate those from my intuitive feet and inch estimates). Neither was particularly practical.
Cody Smith On Wed, Apr 13, 2022 at 10:43 AM Roger Critchlow <[email protected]> wrote: https://news.mit.edu/2022/thermal-heat-engine-0413 Thermophotovoltaic, converts 1900-2400C source photons to electricity at >40% efficiency. -- rec -- .-- .- -. - / .- -.-. - .. --- -. ..--.. / -.-. --- -. .--- ..- --. .- - . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn UTC-6 bit.ly/virtualfriam <http://bit.ly/virtualfriam> un/subscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ archives: 5/2017 thru present https://redfish.com/pipermail/friam_redfish.com/ 1/2003 thru 6/2021 http://friam.383.s1.nabble.com/ .-- .- -. - / .- -.-. - .. --- -. ..--.. / -.-. --- -. .--- ..- --. .- - . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn UTC-6 bit.ly/virtualfriam un/subscribehttp://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIChttp://friam-comic.blogspot.com/ archives: 5/2017 thru presenthttps://redfish.com/pipermail/friam_redfish.com/ 1/2003 thru 6/2021http://friam.383.s1.nabble.com/
OpenPGP_0xFD82820D1AAECDAE.asc
Description: OpenPGP public key
OpenPGP_signature
Description: OpenPGP digital signature
.-- .- -. - / .- -.-. - .. --- -. ..--.. / -.-. --- -. .--- ..- --. .- - . FRIAM Applied Complexity Group listserv Zoom Fridays 9:30a-12p Mtn UTC-6 bit.ly/virtualfriam un/subscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ archives: 5/2017 thru present https://redfish.com/pipermail/friam_redfish.com/ 1/2003 thru 6/2021 http://friam.383.s1.nabble.com/
