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Heliogen, backed by Gates, says it has achieved a solar breakthrough

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51–60 of 107 posts

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#51

Am I missing the breakthrough? This just reads like boilerplate tech marketing, replete with questionable ai usage. I suspect without its well known backer anyone would notice.

They seem to be using computer vision techniques to dynamically aim the mirrors. Presumably static or open-loop techniques don't focus as precisely, and using a closed loop also allows them to reduce the stiffness (and this material use) in their mounts and/or fewer mirrors.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#52

Am I missing the breakthrough? This just reads like boilerplate tech marketing, replete with questionable ai usage. I suspect without its well known backer anyone would notice.

Yes you are. High temperature from concentrated solar power has been something of a holy grail for a while. How it was achieved ("with AI") is less interesting than the result.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#54

Am I missing the breakthrough? This just reads like boilerplate tech marketing, replete with questionable ai usage. I suspect without its well known backer anyone would notice.

They seem to be using computer vision techniques to dynamically aim the mirrors. Presumably static or open-loop techniques don't focus as precisely, and using a closed loop also allows them to reduce the stiffness (and this material use) in their mounts and/or fewer mirrors.

Closed loop enables higher temperature. I doubt material saving is worth it.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#55
post #42

Another interesting problem this might solve is birds. Yes, domestic cats kill orders of magnitudes more birds, but that argument a. depends on relative scale that people don't grok, and b. coming from an energy company reinforces the preconception that they're callous. Add radar and a sufficiently smart AI, and they could turn a PR problem into a marketing pitch by showing birds flying through unscathed while the mi…

Or, direct all mirrors at them and fry them to cinders. Hard to count cinders.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#56

Excerpt: A secretive startup backed by Bill Gates has achieved a solar breakthrough aimed at saving the planet. Heliogen, a clean energy company that emerged from stealth mode on Tuesday, said it has discovered a way to use artificial intelligence and a field of mirrors to reflect so much sunlight that it generates extreme heat above 1,000 degrees Celsius. ===== The article describes a bit about the role the AI is pl…

I fundamentally cannot perceive where AI plays a role. Isn't it just a solvable geometry problem?

Not really. Ground heave/subsidence is the primary cause of misalignment.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#57
post #32

Earlier quoted context omitted.

A sun angle sensor is great for pointing at the sun. Heliostats need to bisect a ray to the sun and one to the target. Installation requires somehow setting the angle to the target. Then you immediately become aware of how much the ground heaves throughout the day, so you have to make a foundation that goes well down into the earth. Now you have a $200 heliostat on a $1000 foundation with a $100 calibration operation…

No, with the photodiodes you can still steer the mirrors. The mirror part doesn't change. Nothing about the installation changes, except you throw out the "AI" and "computer vision" hype.

How do you know where the target is? That's the part where a computer helps. You don't need to see to know where the sun is given a frame of reference, that's just math and a clock. Your frame of reference is initially unknown and varies slightly, but significantly, with time. Training a computer vision system to look for "insanely bright rectangle subtending <1° of space elevated on a stick" is just the thing computer vision is becoming good at. It's even easier than asking my phone to "show me my pictures of goats" (111 hits, zero false positives (assuming sheep are goats)). Of course, a tall skinny field tech should think twice about wearing a short, bulky, white jacket.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#58
post #54

Earlier quoted context omitted.

They seem to be using computer vision techniques to dynamically aim the mirrors. Presumably static or open-loop techniques don't focus as precisely, and using a closed loop also allows them to reduce the stiffness (and this material use) in their mounts and/or fewer mirrors.

Closed loop enables higher temperature. I doubt material saving is worth it.

Pointing hundreds of mirrors is expensive. Requiring a lot less rigidity for the motion system is notable.

I don't doubt you could have done this open loop with a very rigid (expensive) platform before (including solving problems of ground subsidence). But now you can do it with a reasonably priced platform closed loop, which is what makes it actually possible.

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#59
post #49

@elonmusk please work with integrating battery tech with these guys!!

Backing up solar production with batteries is pointless. Except for a really specific cases. The costs are too high, the stress on the grid is too high, the grid need to be overscaled, the batteries need to be changed each 15 years the solar panels need to be changed each 20 years. And even if we overcome this, we will need so much solar panel and batteries that we simply don't have enough raw materials to do so (to…

Yeah true. I heard of another Bill Gates backed startup that actually stored the energy in a form of potential energy which was way more cost effective. Keep in mind though dams are super catastrophic to the environment as far as water flow which can be detrimental to moisture and animals that depend on water in certain areas

Re: Heliogen, backed by Gates, says it has achieved a solar breakthrough

#60

Earlier quoted context omitted.

>or each plant you build you need the exact position of each mirror, the oven chamber and the motion of the sun through the day and year Yeah, depending on the level of precision required, there are _tons_ of variables that could have an impact here. Year to year the angle of the sun changes slightly on any given solar date, as various components of the Earth's orbit "wobble" (axial tilt, eccentricity, precession, et…

The motion of the Earth in space is very well determined and studied; the thermal expansion and deformation of the structure is most likely the dominant source of uncertainty for the pointing.

Ground subsidence and related structural effects on the mirrors and mirror field are the main issue.

But also the position of the sun in the sky is not predictable enough to do this completely open loop because of variances in atmospheric refraction... but it's pretty easily measured at the site.

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