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> Another innovation suggests that artificial intelligence could make CSP more competitive. Heliogen Inc., a CSP company backed by Bill Gates, uses computer vis

by pintxo 4y ago

> Another innovation suggests that artificial intelligence could make CSP more competitive. Heliogen Inc., a CSP company backed by Bill Gates, uses computer vision to track the sun and continually adjust the mirrors in a CSP plant to maximize the concentration of sunlight. Is this a journalist not getting it? Why would we need computer vision to track the position of the sun? > That takes some of the complexity out of building a CSP system, which lowers construction costs. In current systems, mirrors have to be painstakingly installed in the best possible position. Even then, the ground can shift and stop concentrating the sunlight as effectively, according to Bill Gross, Heliogen’s CEO and founder. Ok, maybe it's more about the continuous optimization of the mirror positioning.

tlb 4y ago
It’s hard to adjust one mirror at a time, because 1000 other mirrors are reflecting at the same spot. And you can’t put a camera on the target to look back at the mirrors, because it would get melted. And some errors are harmless, like aiming too high, but aiming too low can melt the tower. And you have to do all the aiming with cheap linear actuators that aren’t very stiff, so wind affects everything. I dunno about AI, but it is a problem that programmers have struggled with so it might be worth a try.
- manholio 4y ago
  > And you can’t put a camera on the target to look back at the mirrors, because it would get melted. So just put it behind a heavy metalized filter that reflects over 99% of the incoming energy? And suspend the whole assembly about 1 meter in front of the target on a metalic post so it can cool down in the air. Or rather, a number of such assemblies so you can maximize incident energy over the entire target. Optimizing that does not sound like a deep learning problem, just a classic computer vision algorithm.
  - tlb 4y ago
    Maybe. Just remember that an extra 1% of efficiency is worth 1% of the billion-dollar project cost, so there’s pressure not to have sensors blocking even a tiny part of the view.
  - londons_explore 4y ago
    Or just put the camera somewhere else. Then point one mirror at a time at the camera (therefore, it only seex 1x sunlight) to do angle calibration, and then aim that mirror back at the proper target and calibrate the next.
- zardo 4y ago
  If actuators to keep the mirrors oriented correctly really do blow the budget then this sounds like a dead end.
  - tlb 4y ago
    It's not black & white. You want to use the cheapest actuators you can get away with. If clever software lets you use less precise actuators, it's a big win.
- buescher 4y ago
  You could have position feedback on the mirrors and periodically calibrate the transfer function of mirror position to focus point at night.
  - always2slow 4y ago
    I bet the mirror will heat up during the day and your night calibration will be off.
    - buescher 4y ago
      Good point.
deleted 4y ago
[deleted]
lscharen 4y ago
Given the existence of passive solar trackers that work mechanically, it's really hard to see how a complicated active tracking system could possible outcompete for a PV system. However, the company in the article is involved in concentrated solar power, so perhaps the situation is different enough to warrant such a system. I can _sort of_ see how there could be a feedback loop where changing ambient temperatures and radiative heat from the tower might effect the reflective array in complicated ways that would make it hard to maintain a very tight focus point. And, if tightening the focus point of the array can double or triple the incident W/m^2, maybe that gets past some sort of pass/no-pass temperature threshold that allows for higher overall energy conversion....
sigstoat 4y ago
> Why would we need computer vision to track the position of the sun? jpl horizons can tell anyone with a web browser where in the sky the sun will appear at any point in the next... hmm. ~477 years, it seems. so there's got to be something more going on.
ttyprintk 4y ago
The early designs were required to redirect the mirrors on cloudy days. Sudden full sun would damage the tower. The largest CSP has half a million mirrors.

by pintxo 4y ago

tlb 4y ago

It’s hard to adjust one mirror at a time, because 1000 other mirrors are reflecting at the same spot. And you can’t put a camera on the target to look back at the mirrors, because it would get melted. And some errors are harmless, like aiming too high, but aiming too low can melt the tower. And you have to do all the aiming with cheap linear actuators that aren’t very stiff, so wind affects everything. I dunno about AI, but it is a problem that programmers have struggled with so it might be worth a try.

manholio 4y ago
> And you can’t put a camera on the target to look back at the mirrors, because it would get melted. So just put it behind a heavy metalized filter that reflects over 99% of the incoming energy? And suspend the whole assembly about 1 meter in front of the target on a metalic post so it can cool down in the air. Or rather, a number of such assemblies so you can maximize incident energy over the entire target. Optimizing that does not sound like a deep learning problem, just a classic computer vision algorithm.
- tlb 4y ago
  Maybe. Just remember that an extra 1% of efficiency is worth 1% of the billion-dollar project cost, so there’s pressure not to have sensors blocking even a tiny part of the view.
- londons_explore 4y ago
  Or just put the camera somewhere else. Then point one mirror at a time at the camera (therefore, it only seex 1x sunlight) to do angle calibration, and then aim that mirror back at the proper target and calibrate the next.
zardo 4y ago
If actuators to keep the mirrors oriented correctly really do blow the budget then this sounds like a dead end.
- tlb 4y ago
  It's not black & white. You want to use the cheapest actuators you can get away with. If clever software lets you use less precise actuators, it's a big win.
buescher 4y ago
You could have position feedback on the mirrors and periodically calibrate the transfer function of mirror position to focus point at night.
- always2slow 4y ago
  I bet the mirror will heat up during the day and your night calibration will be off.
  - buescher 4y ago
    Good point.

deleted 4y ago

[deleted]

lscharen 4y ago

Given the existence of passive solar trackers that work mechanically, it's really hard to see how a complicated active tracking system could possible outcompete for a PV system. However, the company in the article is involved in concentrated solar power, so perhaps the situation is different enough to warrant such a system. I can _sort of_ see how there could be a feedback loop where changing ambient temperatures and radiative heat from the tower might effect the reflective array in complicated ways that would make it hard to maintain a very tight focus point. And, if tightening the focus point of the array can double or triple the incident W/m^2, maybe that gets past some sort of pass/no-pass temperature threshold that allows for higher overall energy conversion....

sigstoat 4y ago

> Why would we need computer vision to track the position of the sun? jpl horizons can tell anyone with a web browser where in the sky the sun will appear at any point in the next... hmm. ~477 years, it seems. so there's got to be something more going on.

ttyprintk 4y ago

The early designs were required to redirect the mirrors on cloudy days. Sudden full sun would damage the tower. The largest CSP has half a million mirrors.