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Heliogen targets 1500°C solar thermal

vox.com

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Re: Heliogen targets 1500°C solar thermal

#31

Post by usrusr »

ygra wrote: post #24
VBprogrammer wrote: post #18

Earlier quoted context omitted.

The problem is generally trivial compared to the number killed by domestic cats and glass windows.

For wind turbines at least there's a bit of a difference, as those kill larger birds than cats, in smaller numbers, but those birds also have smaller populations. So just looking at the numbers without knowing the birds and their total populations, makes things hard to compare or judge.

But aren't most larger birds predators that are highly habitat/food supply constrained? That kind of population could be quite resilient to moderate increases in mortality.

(I might be assigning far more importance to predator-Peru cycles than is warranted though, I was reading about what I now found is called https://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equatio... at a very young age and the concept stuck for life)

Re: Heliogen targets 1500°C solar thermal

#32

Post by trickstra »

tempodox wrote: post #30

Inertia must be incredibly strong. Otherwise, why did it take so long to come up with something that strikingly simple? The last time someone allegedly had an idea like that was around 212 B.C., in the defense of Syracuse.

Because of oil lobby mostly. The idea is nothing new, it was just easier to burn oil instead of building new industry from ground up and going against all existing oil companies.

Re: Heliogen targets 1500°C solar thermal

#33

Post by giarc »

kwhitefoot wrote: post #20
zubspace wrote: post #15

Another similar project in the mojave desert incinerates 6000 birds a year [1]. I wonder, how they handle that.. [1] https://www.sciencealert.com/this-solar-plant-accidentally-i...

Is 6000 birds a year a lot? It's a serious question, I have no idea what fraction of birds in the area that is. Is it comparable to the normal fluctuation in bird mortality in the area or is it so large that it has a disturbing effect on the population? Of course fewer bird deaths would be good, and zero would be better. But these bird deaths are noticed because of where they occur. What is the 'background' level, th…

I recall seeing a chart one day that showed bird deaths by source. Death by domestic cats were magnitudes higher than any other source.

Re: Heliogen targets 1500°C solar thermal

#34

Post by sambull »

pjc50 wrote: post #23
ReptileMan wrote: post #10

Earlier quoted context omitted.

What exactly do you need AI for except for buzzwording? It is not as if the sun/earth trajectory or rotation speed is random. You can precalc with ease at every point which is the best position for each mirror.

The difficult problem is not knowing where the sun is but knowing where the ground is. Since all the panels are separate structures not on a single rigid slab, ground "settling" can tilt them fractionally in unpredictable ways. It sounds like what they have is machine vision as a novel input into a conventional control loop. For one panel at a time, wiggle it about and look how the light spot changes. Find the local…

Interesting, and all that is done by some flowers in my yard; I wonder if the flowers are artificially intelligent.

Re: Heliogen targets 1500°C solar thermal

#35

Post by marvin »

ovi256 wrote: post #26
TeMPOraL wrote: post #13

Earlier quoted context omitted.

I'd imagine that the "few thousandths of a degree" is something you'd get worse with AI than with a mathematical model. AI methods introduce noise; with an explicit model you can keep adding complexity directly, until it gets more accurate than your measuring system. I suspect that the "AI" they mention is mostly photogrammetry - being able to tell the position and orientation of your mirrors from a video stream - in…

>mostly photogrammetry - being able to tell the position and orientation of your mirrors from a video stream - in a feedback loop with motor controllers and temperature sensors. This. Modern photogrammetry uses computer vision techniques like deep neural nets. It's an amazing advancement. Imagine this problem: having to place a ground vehicle like a wheeled robot at an arbitrary coordinate in a room. The mirror posit…

How do you train this? By example? Would enjoy seeing an example of this :)

Re: Heliogen targets 1500°C solar thermal

#37

Post by klyrs »

sambull wrote: post #34
pjc50 wrote: post #23

Earlier quoted context omitted.

The difficult problem is not knowing where the sun is but knowing where the ground is. Since all the panels are separate structures not on a single rigid slab, ground "settling" can tilt them fractionally in unpredictable ways. It sounds like what they have is machine vision as a novel input into a conventional control loop. For one panel at a time, wiggle it about and look how the light spot changes. Find the local…

Interesting, and all that is done by some flowers in my yard; I wonder if the flowers are artificially intelligent.

You can replicate this behavior with four solar panels mounted on a motorized platform. The panels should be at a slight angle, with a peak in the middle... then a voltage differential top-to-bottom activates the vertical motor, likewise the horizontal motor.

I'm not sure how to make such a simple system for mirrors pointing at targets, but I suspect "AI" and "cameras" are overkill.

Re: Heliogen targets 1500°C solar thermal

#38

Post by thinkcontext »

Juliate wrote: post #3

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 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.

Here's a better article which explains the advantages over traditional 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.

Re: Heliogen targets 1500°C solar thermal

#39

Post by aj7 »

Very skeptical that this is a practical means to supply 1500C to an industrial process. Do they plan on piping heat via liquid metal, or what? Do you shutdown on cloudy days and sen everyone home?
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