I built an open-source, AI-powered solar panel that's 95% optimal (opens in new tab)

Thermal for heating/hot shower or thermal for some adventure in driving a generator?

For heating, photovoltaics supplying a heat pump is starting to give direct thermal a run for the money (well, not actually for the money yet, direct thermal is still cheaper, but at least in terms of how much you could harvest from a given roof area)

If money isn't an objection at all, e.g. if you strive for that sense of achievement of a good setup, there are hybrid modules that pick up the 20% or so photovoltaics achieves and still funnel the remaining energy into heating a liquid medium.

1885 - invention of process for seamless steel pipes from bar stock, Development History of Seamless Steel Pipe, https://www.supplychainquarterly.com/articles/3787-the-devel...

1954 - first practical silicon solar cell, Timeline of Solar Cells, https://en.wikipedia.org/wiki/Timeline_of_solar_cells

the US is a metric country that's in denial

if you're buying construction supplies in north america you're not going to get metric sized pipes for like, sticking a robust mast in the ground.

whereas 54, 60, 72-cell pv panels with aluminum frames made from 156mm cells are manufactured in metric dimensions.

I remember a guy in a community that I frequent that build a small trailer that had fixed solar panels, he had build one for a reason I don't remember and afterward some companies were interested and that post was showing his second one he had just sold. It was a bunch of panels on an A frame so essentially one side had awful sun visibility but not the other. People wondered why he did it in such ways, as that meant that half the time they would be useless, why not a moving platform on a central pivot that you can adjust? Well turns out it was cheaper to add panels on the other sides than building a more complex frame that allowed pivot. I'm sure it could have been cheaper to build a system sure (maybe not in his case considering it was on a trailer), but I have an hard time believing the maintenance cost and failure potential is worth it. You can just add more panels... they are starting to become that cheap.

As GP argued, the movement can be entirely precomputed, and even if it isn't "move the panel to face the brightest spot" is trivial to solve with simple components. The only real advances I can imagine to make this profitable would be better motors that are cheaper and use less energy, or new types of solar panels that are more directional (e.g. a solar concentrator setup where you move mirrors to hit a smaller collector).

The latter exist but don't seem more profitable (in the case of PV panels because of lifetime problems due to more heat), and while we have gotten a bit better with motors I don't think there even is a lot of headroom to gain much efficiency.

Another concept involving the cooling of solar panels and how to use the heat:

https://www.youtube.com/watch?v=-dJixtZdkU0

Interesting that the limiting factor is energy and wind. I wonder if you could devise a locking mechanism or something purely mechanical to solve it. Something closer to gears in a watch.

The intverter should be able to be configured with export limits. In a lot of jurisdictions that's mandatory anyway. Still better to over-specify so that in Winter you get the full amount while in Summer you just throw some away. Or take up a power-intensive hobby like Bitcoin mining in Summer.

Yes. A 400w watt panel is 250$. When you account for labor and cost of all. The parts for a moving panel that can withstand high wind speeds…Placing more fixed panels is cheaper.

Our solar panels are rated to 115mph winds. What are these servo mounts rated to?

Also, installation of the panels currently costs more than panels. They don't say (or I didn't find) how efficient the optimal fixed mount is, but the agent starts at 80%, so assume some fixed position is 80% of optimal. They increase that to 96%, so they reduce the number of solar panels by about 13%. If the installation labor cost increases more than ~26% because of the servo mount, then the servo mount hardware and frame would need to be cheaper than fixed mounts for it to break even. Similarly, the amount of aluminum being consumed by solar panel installions is non-trivial, and the movable frame is likely to increase that.

However, this is still a cool hobby project with a nice writeup.

Maybe not bulk cost upfront, but surely the maintenance cost tips towards fixed place panels.

And? I was going to type out a reply but got me curios whether this is a solved thing already.

It is a thing already: http://www.sulasindustries.com/technology/

I raced solar cars in college. One car we built had a solar concentrator system made up of 1D parabolic mirrors. This was a several hundred thousand dollar system due to the use of specialized concentrator cells, and required multiple team members to temporarily move to LA for months to delicately manufacture the cells in a Spectrolab clean room.

The concentrator mirrors had to be aimed within about 2 degrees to aim the light onto the active area of the cells. I tried using a pair of photodiodes as the sensor, and it worked well in early prototypes. We flew out to Australia before the system was fully integrated into the car, though. In the real setup it just wasn't precise enough. On top of that, the aerodynamically shaped acrylic window surfaces created weird refractions and reflections that made the accuracy poor as well.

I had a couple weeks to figure something out, with a bunch of PIC18F4680 MCUs on hand, and access to parts from Dick Smith's. I ended up buying a small PAL security camera to experiment with. I went to a nearby photo center and got some overexposed film negative to use as an IR-passing filter. With enough layers of film, the camera image was completely black other than a white dot when pointed at the sun. Looking at the analog video signal on a scope, I was able to rig up a couple fine-tuneable voltage dividers and then use the MCU's dual comparator peripheral to generate interrupts on sync pulses and on white pixels. I could then count scan lines, and detect scan lines with the sun in them, giving me a Y coordinate precise to a fraction of a degree. I also got an X coordinate by timing between syncs and white pixels, but I didn't need it for control. I then mounted the camera on the concentrator mechanism, and wrote a basic PID controller.

It worked pretty well, and we were able to happily concentrate sunlight while driving at highway speeds.

It turned out the linear servo mechanism had a design flaw, where it would lose too much mechanical advantage at the extremes, and in the presence of road vibrations it would jam. We discovered this fairly early on in the race. Luckily I had wireless control of the motor over our telemetry system, allowing me to keep the motor from burning out. We drove a couple hours with the system jammed, taking the power hit over losing race time. Someone realized we would be driving over a "cattle grid" soon, and we had the idea to try running the motor at full torque to see if the shock would be enough to unjam the mirrors. It worked, and we suddenly started getting several hundred watts of additional power! After that day, we tied a string to the mechanism and routed it up to the driver cockpit. Whenever the mirrors got stuck after that, we simply radioed the driver and they gave the string a yank.

When they say "may vary", they mean by a fraction of a degree! Astronomers care a lot about precisely accounting for atmospheric refraction because if you want to look at a specific star or whatever, it kind of matters that you point your telescope in exactly the right direction. But for just pointing a solar panel roughly towards the sun, the simplified model from that site should be more than sufficient.

Only if the additional cost and complexity of such a setup is worth said cost. It can also be used to move the panels into approximately the correct location then allow the other techniques to fine tune it. If the more complex systems have a fault it may be possible to fall back to the more simple method which, while probably not as good, would be more efficient then just a static panel.

A GPS receiver can be had for like $15 these days. That will give you time and position, and require less maintenance than an RTC.

Of course, a $15 receiver might not have the best sensitivity, so reception might actually be a practical concern. On the other hand, you only need 4 satellites for a coarse fix, and you could seemingly tolerate a many minute cold fix time.

It provides reasoning as to why it is a better solution than just pointing at the sun.

Farmers are placing them mounted vertically, like fences, in productive fields, running north/south, far enough apart to run a tractor between. They pick up power in morning and afternoon. The crops benefit from reduced heat stress and water loss, and yield more.

Panels that work with light from either side are preferred for this use.

If it’s not hardware (panels, inverters, brackets, etc) it is considered a soft cost.

NREL’s model puts soft costs at 44% for a 100MW fixed-tilt utility-scale plant in 2021:

https://www.nrel.gov/docs/fy22osti/80694.pdf

The percentage goes up as the installation size goes down, but it is not 70%

>low altitude

Low latitude?

Yes, but that's a different topic. And isn't this just an exploratory project rather than an engineering effort or scientific research?

But even then, I got panels on my roof last year. A nearby tree that was trimmed when we installed them and now the shade partially covers panels in the morning. If we had gimbles perhaps they'd be more efficient. Maybe not, and maybe we should trim the tree, but the point is that perhaps there is a use case that hasn't been thought of yet. Say, dropping cells on mars in a relatively unknown environment.

I'm more and more convinced of this. Control theory appears to be like lightsabers, "a refined weapon for a more civilized age". It's really unfortunately that the controls literature is so opaque.