Why don't they just make dish shaped solar panels?

for photovoltaic panels i dont think theres any benefit; at least that i know of.

but for panels that work by heating a fluid theyre already doing it (Parabolic trough)

>>16709638 (OP)
With PV cells you want to maximize the surface area-to-sunlight ratio. In other words, you want them flat.

In the pictured example, the energy available is equal to the solar energy per unit area times the area of the circle, irrespective to the depth of the dish.

A reflective dish will concentrate that energy into a single point. But for PV cells you're just using more surface area to collect the same amount of sunlight.

>>16709641
as anon says

ideally, you want your panels to be pointed directly at the sun. the solar flux varies with angle as a cosine until it hits zero at 90 when the panel is facing orthogonal to the sun.

also it's hard to grow non-planar semiconductors

perhaps solar panels could be combined with a heated fluid to make use of any reflected light not absorbed by the solar panels

German meme plant down in Sahara did that
>did it work
Yes, but then the CCP decided to mass produce solar, bringing down the cost per Watt extracted, making the solar focus stuff hideously expensive side by side.

You also need to deal with the mirrors warping, and the extractor overheating. Meanwhile normal solar panels only really has to deal with material fatigue,, which barely exist when its a quantom mechanic effect.

>>16709638 (OP)
>Why don't they just make dish shaped solar panels?

Actually they now make them flat, and just lay them on the ground

>>16709638 (OP)
Because it makes no sense to, that shape would direct sunlight to the middle meaning the edges would get less sunlight than the center and the center panels could get very hot thus making them less efficient.

>>16709858
but semiconductors have a negative thermal resistance coefficient

>>16709638 (OP)
You can put reflectors around your panels to get more sunlight per panel.
You need to find a way to handle the extra heat to avoid shortening panel lifespan, though.

>>16709638 (OP)
They should make it convex if you think about it

>>16709638 (OP)
They do, they put one of these expensive 40% efficiency cells at the focal point, and just blast it with concentrated sunlight. It needs to be water cooled btw

>>16709759
that only works in the southern hemisphere

>>16709638 (OP)
It is not beneficial when it is overcast and only cost effective when the dish is so large that it is suited only for commercial plants.

>>16709759
It is best when you raise them a little, by an angle about that of the latitude.

>>16710075
Rather in equatorial regions.

>>16709638 (OP)
there's a solar power plant near las vegas called helios one where they did that.
don't ask me any questions about its inner workings though, i only have a theoretical degree in physics.

>>16710946
Top kek
You'll get the 22 this time instead of a MIRV

>>16710946
oh, looks like that's a real power plant.
they built it twice in nevada, and then tore it down to build it a third time in spain.
https://en.wikipedia.org/wiki/The_Solar_Project
maybe it just doesn't get sunny enough for solar power in the US.

i don't know how the efficiency compares to photovoltaic solar power, but i just read, that thermal solar power can store its hot coolant for later.
that way you could combat the duck curve with renewable sources without having to resort to batteries, pump storage, or hydrogen electrolysis.
it doesn't last forever, but all you need is a big thermos.

>>16709638 (OP)
they do some other way

>>16709638 (OP)
because PV cells are heat sensitive
the hotter they run, the less efficient they are and the faster they destroy themselves
back when c-Si was worth its weight in gold, it would have been worth it trying to do all kind of engineering workarounds like tracking mirror arrays and water cooled collector

now c-Si is cheap enough that doing anything more complicated than bolting it down vaguely towards south is burning money

>>16710958
Thermo solar isn't very good at the moment compared to photovoltaic, its kind of an expensive clusterfuck just to produce intermittent power. Thermo storage could live on with other heat sources though

>>16711023
I guess the nice part to me, who hasn't looked at the actual efficiencies and engineering problems, is that there are less conversion steps for solar thermal.
it's just solar -> heat -> electricity.
assuming you want to store most power for a while, photovoltaic would go solar -> electricity -> thermal -> electricity.
or go through a different conversion, if a different energy storage is used.

but thermodynamic efficiency alone is only part of the final energy cost, i suppose.

>>16711025
Grid batteries and pumped hydro are good these days, they use those now for storing solar power. Batteries aren't cheap but apparently cheap enough to be useful now.

The application for thermal storage I am excited about is
Nuclear -> Heat -> Electricity
Solar -> Electricity
Then we can use solar electricity during the day, then "boost" the power of nuclear plants at night to make up for the shortfall.

>>16711031
How well have gravity battery systems evolved? I remember some system using stacking and rail tracks they claimed was pretty scalable

>>16711034
They haven't gone anywhere last I checked, pumping water up hills is still the standard for gravity storage. In California regular old batteries are becoming pretty relevant for meeting evening demand, so I guess the stupid solution won for the time being.

Like I said though, nuclear reactors with thermal energy storage, right now its not what is hyped but I am telling you that is the shit that's gonna scare gas executives in 10 years.

https://www.nrc.gov/reactors/new-reactors/advanced/who-were-working-with/applicant-projects/terrapower.html

>>16711038
ok just google the name, the NRC documents are mostly concerned with safety shit you get with any nuke plant and is pretty boring lol

>>16711004
>because PV cells are heat sensitive
They are water cooled
Focusing means you replace almost all the solar cell area with mirrors, then you can invest in the most expensive and efficient solar cells, the type they use in sattelites with ver 40% efficiency
They do this by stacking solar cells, the PN junctions, of different materials sensitive to different wavelengths, so you use as much of the spectrum as you can

>>16709638 (OP)
because a PV panel is not a reflector
Why dont they make spray cans using a vacuum instead of positive pressure?
Why dont they make convex frying pans? Why dont they make octagonal automobile tires?