10 ms·

https://en.wikipedia.org/wiki/Odeillo_solar_furnace https://en.wikipedia.org/wiki/Odeillo_solar_furnace "started operating in 1970", "Temperatures above 3,500

https://en.wikipedia.org/wiki/Odeillo_solar_furnace https://en.wikipedia.org/wiki/Odeillo_solar_furnace "started operating in 1970", "Temperatures above 3,500 °C (6,330 °F) can be obtained in a few seconds". See also https://en.wikipedia.org/wiki/Solar_furnace https://en.wikipedia.org/wiki/Solar_furnace Not dismissing this press release, but at least some scale of progress should be used to compare against. Or state where the economical/industrial/regulatory innovation stands.

scoopertrooper 7y ago
That thing is the size of a building though.
- Juliate 7y ago
  Granted. Size and lightweightness are definitely a point - that could be emphasized as a major argument - even the ratio with size & power capacity & heat intensity.
  - agumonkey 7y ago
    I wonder how security is handled there
    - astrodust 7y ago
      Oh man what if someone stole the sun. (In all seriousness, the security risks are pretty low here. This isn't like stealing nuclear fuel.)
      - agumonkey 7y ago
        Sorry I meant safety.
baq 7y ago
yeah the only problem is the useful heat is contained in a very small area/volume, so this is only a research facility.
- reportgunner 7y ago
  AFAIK the solar towers actually use molten salts to store the heat in tanks so they can keep going even overnight.
  - ginko 7y ago
    Not sure which salts would be used here, but I 1500C+ is pretty hot even for many salts. Sodium chloride boils a bit below that(1465C) for instance.
    - Beltiras 7y ago
      Molten salt towers don't heat above 800 iirc. If they were designed for storing more energy it would come from more mass. It goes without saying that the benefit of salt is reduced once it becomes gasified.
      - chrisbrandow 7y ago
        In a technical sense, that would depend in part on the salt. If a salt with a higher melting point existed then it could be stored at a higher temperature. I’m not meaning to “correct” your statement, because the actual practicalities of these systems Is not my expertise and there may be other much more significant factors to consider
    - semi-extrinsic 7y ago
      Even if the surface temperature of the solar collector focus point is 1500C, the molten salt flowing on the other side of that wall must be at a significantly lower temperature in order to transfer heat quickly enough from the small area. Then you will have a thermal profile in the wall, say from 1500 to 1200 C, and furthermore a thermal boundary layer in the fluid, say from 1200 to 800 C.
thinkcontext 7y ago
Here's a better article which explains the advantages over traditional CSP. https://www.vox.com/platform/amp/science-and-health/2019/11/19/20970252/climate-change-solar-heat-heliogen-csp https://www.vox.com/platform/amp/science-and-health/2019/11/... TL;DR Traditional CSP is aligned once, Heliogen aligns continuously. This allows them to correct for individual panel changes in warping, settling, weather, dust, etc. This approach also allows them to use cheaper hardware.
- baybal2 7y ago
  Well... no. Motors and circuitry on each mirror instead of a simple screw drive are certainly not making the setup cheaper It smells to me like a second Solindra in making
  - deleted 7y ago
    [deleted]
  - thinkcontext 7y ago
    You didn't bother to read the article. > Rather than assembling large, complicated, curved heliostats (mirrors) on site, eSolar used small, flat, prefabricated heliostats of only about a square meter. They were cheaper, faster and easier to set up, more modular, and easier to replace. > Gross’s key insight was that he could replace a lot of the material and labor involved in CSP with computing power. (Or, he could replace stuff with intelligence.) Rather than make bigger, more complicated mirrors, he made small, simple ones and controlled them with software, so they stayed aligned more precisely and produced more power.
    - baybal2 7y ago
      > You didn't bother to read the article. I did, their entire premise is invalid. They are either very bad at math, or engineering, or both. The metal part, screw drive, and simple pulleys and etc are nor hard, nor expensive. Saying it otherwise is purest bs. The limits of precision of theodolite are more than enough position for precise initial reference. Existing solar thermal farms were not designed for generation of process heat in mind to begin with, so them saying that they suck at that because of their "design" is a PR trick. Existing thermochemical processes are profitable enough to burn oil for them, and if one minds anything cheaper, they will first consider CHP colocation before thinking of anything as weird as this.

scoopertrooper 7y ago

That thing is the size of a building though.

Juliate 7y ago
Granted. Size and lightweightness are definitely a point - that could be emphasized as a major argument - even the ratio with size & power capacity & heat intensity.
- agumonkey 7y ago
  I wonder how security is handled there
  - astrodust 7y ago
    Oh man what if someone stole the sun. (In all seriousness, the security risks are pretty low here. This isn't like stealing nuclear fuel.)
    - agumonkey 7y ago
      Sorry I meant safety.

baq 7y ago

yeah the only problem is the useful heat is contained in a very small area/volume, so this is only a research facility.

reportgunner 7y ago
AFAIK the solar towers actually use molten salts to store the heat in tanks so they can keep going even overnight.
- ginko 7y ago
  Not sure which salts would be used here, but I 1500C+ is pretty hot even for many salts. Sodium chloride boils a bit below that(1465C) for instance.
  - Beltiras 7y ago
    Molten salt towers don't heat above 800 iirc. If they were designed for storing more energy it would come from more mass. It goes without saying that the benefit of salt is reduced once it becomes gasified.
    - chrisbrandow 7y ago
      In a technical sense, that would depend in part on the salt. If a salt with a higher melting point existed then it could be stored at a higher temperature. I’m not meaning to “correct” your statement, because the actual practicalities of these systems Is not my expertise and there may be other much more significant factors to consider
  - semi-extrinsic 7y ago
    Even if the surface temperature of the solar collector focus point is 1500C, the molten salt flowing on the other side of that wall must be at a significantly lower temperature in order to transfer heat quickly enough from the small area. Then you will have a thermal profile in the wall, say from 1500 to 1200 C, and furthermore a thermal boundary layer in the fluid, say from 1200 to 800 C.

thinkcontext 7y ago

Here's a better article which explains the advantages over traditional CSP. https://www.vox.com/platform/amp/science-and-health/2019/11/19/20970252/climate-change-solar-heat-heliogen-csp https://www.vox.com/platform/amp/science-and-health/2019/11/... TL;DR Traditional CSP is aligned once, Heliogen aligns continuously. This allows them to correct for individual panel changes in warping, settling, weather, dust, etc. This approach also allows them to use cheaper hardware.

baybal2 7y ago
Well... no. Motors and circuitry on each mirror instead of a simple screw drive are certainly not making the setup cheaper It smells to me like a second Solindra in making
- deleted 7y ago
  [deleted]
- thinkcontext 7y ago
  You didn't bother to read the article. > Rather than assembling large, complicated, curved heliostats (mirrors) on site, eSolar used small, flat, prefabricated heliostats of only about a square meter. They were cheaper, faster and easier to set up, more modular, and easier to replace. > Gross’s key insight was that he could replace a lot of the material and labor involved in CSP with computing power. (Or, he could replace stuff with intelligence.) Rather than make bigger, more complicated mirrors, he made small, simple ones and controlled them with software, so they stayed aligned more precisely and produced more power.
  - baybal2 7y ago
    > You didn't bother to read the article. I did, their entire premise is invalid. They are either very bad at math, or engineering, or both. The metal part, screw drive, and simple pulleys and etc are nor hard, nor expensive. Saying it otherwise is purest bs. The limits of precision of theodolite are more than enough position for precise initial reference. Existing solar thermal farms were not designed for generation of process heat in mind to begin with, so them saying that they suck at that because of their "design" is a PR trick. Existing thermochemical processes are profitable enough to burn oil for them, and if one minds anything cheaper, they will first consider CHP colocation before thinking of anything as weird as this.