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Semi-transparent solar panels allow concurrent production of crops and power

onlinelibrary.wiley.com

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Re: Semi-transparent solar panels allow concurrent production of crops and power

#191

Post by simcop2387 »

Nition wrote: post #188
nostoc wrote: post #180

Earlier quoted context omitted.

No, a blue filter, like a blue plastic bag would let blue pass and absorbe the other colors. That's why if you shine a white light through a blue filter, things look blue on the other side. Now, some of the blue light is scattered away, and that's why you see the plastic bag itself as blue.

Hang on, so if you shine a white light through a blue filter, the light on the other side looks blue. And the filter itself still looks blue on both sides. But then, where did the non-blue component of the light go?

Converted to heat. What's going on here is a discussion about transmission and transmittance. [1]

[1] https://www.swiftglass.com/blog/key-differences-transmission...

Re: Semi-transparent solar panels allow concurrent production of crops and power

#192

Post by kube-system »

dTal wrote: post #111
khawkins wrote: post #21

Only people who spend most of their life in densely crowded cities could think that the planet has so little space that you'd need to grow crops underneath solar panels for efficiency's sake.

And only someone blind to the ecological damage that agriculture does would regard all that land as free to use by humans, without consequences. Here [0] is a map of the world's remaining wilderness. Notice how it's nearly all desert, with the exception of the Amazon rainforest. And hey, guess what's happening to that? We are short of space. And time. [0] https://images.theconversation.com/files/256144/original/fil..…

“wilderness” is defined as places generally untouched by people at all, not land that is unused. The vast majority of the unmarked areas of that map are still unused.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#193

Post by chongli »

felipemnoa wrote: post #183
BurningFrog wrote: post #112

Earlier quoted context omitted.

The oxygen claim doesn't inspire confidence. Plants don't produce any useful amount of oxygen, and real scientists know that.

>>Plants don't produce any useful amount of oxygen, and real scientists know that. Could you please add some context to this statement. It is hard to believe that the oxygen produced by plants is so negligible as to be useless. Why?

Because plants use up oxygen when they decay, or when they’re digested by herbivores, and release CO2 in the process. Plants are carbon neutral for this reason.

Oxygen comes from algae in the ocean. The reason the ocean carbon cycle isn’t carbon neutral is because the carbon is fixed into calcium carbonate by zooplankton that feed on the algae. When these tiny animals die their calcium carbonate based exoskeletons sink and accumulate on the ocean floor, sequestering the carbon there.

Carbon sequestration used to take place on land as well (that’s where all fossil fuels originate) but now we have fungi and animals like beetles that can break down lignin and cellulose instead of allowing it to accumulate.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#194

Post by titzer »

BurningFrog wrote: post #112
Communitivity wrote: post #16

Not just crops and power. I know a guy whose startup is using transparent solar panels in Germany on eco-friendly buildings with grass on roofs, to get power and eco-cooling, as well as Oxygen production - at least that is how he explained it. The concept is called green-roofs. Unfortunately I don't remember his startup's name. A link with details about the concept, minus the use of transparent solar panels: https://…

The oxygen claim doesn't inspire confidence. Plants don't produce any useful amount of oxygen, and real scientists know that.

lmgfy

https://www.thoughtco.com/how-much-oxygen-does-one-tree-prod...

A fully mature tree produces anywhere from 2 to 10 persons-worth of oxygen.

I too am skeptical about the amount of oxygen that can be usefully produced by rooftop plants. Yet I still think it is a good idea.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#195

Post by kube-system »

vbezhenar wrote: post #160
khawkins wrote: post #21

Only people who spend most of their life in densely crowded cities could think that the planet has so little space that you'd need to grow crops underneath solar panels for efficiency's sake.

You need logistics (electricity, roads, water). It costs a lot. It's more efficient to utilize 3D rather than utilizing only 2D. When we're talking about humans, I'd agree that living in a crowded city is a terrible thing (though some people might like it). But when we're talking about industrial objects, efficiency is important.

If the space is available, it is nearly always cheaper and more efficient to build horizontally.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#196

Post by kube-system »

gmueckl wrote: post #165
jameslk wrote: post #22

Earlier quoted context omitted.

The solar panels on roads idea has been tried. Rotting leaves were a big source of its failure. https://www.businessinsider.com/first-solar-road-france-fail...

One thing that I don't get about this and related stories: if the road surface is damaged as badly as they say, then why are there no pictures of the damage (the one picture showing damaged modules is described as not taken from modules instLled on the road)? Also, I googled several other stories and none of them has hard facts on why it failed, essentially speculating about different reasons. Something about this st…

I can’t read the article, but previous articles I have read on the subject indicated that the road authorities who evaluated the tech never found it suitable to install on a public roadway to begin with. Besides the durability/maintenance issues, it also had lower friction than a normal road surface. I think one here in the US gave it a trial run as a sidewalk and even that use was a failure when the freeze and thaw cycle of the ground broke them.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#197

Post by hombre_fatal »

asquabventured wrote: post #166
dawnerd wrote: post #154

Earlier quoted context omitted.

All of my plants this year have gotten blossom rot, pretty much too late to fix too. No tomatoes for me this year.

Blossom end rot is caused by calcium deficiency. Easiest solution for this is to just crush up egg shells and put them in and on top of the soil. I save my eggshells in a jar in the fridge for a few months prior to planting. It may be too late for this year but should work wonders for you in the future.

I had deformed cumquats from my tree until I started blending egg shells in the spice blender and watering them into the tree base.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#198

Post by kube-system »

evan_ wrote: post #108
ape4 wrote: post #11

Earlier quoted context omitted.

Vehicles often crash into things beside a highway.

That will surely be taken into consideration from the start, and they will be designed in easily replaceable sections. If a car hits a section maybe it will be disabled but the rest of the cells will be fine and a crew will be dispatched to repair or replace the damaged cells.

Surely it is cheaper to simply place the panel somewhere else than it is to:

1. Pay for thousands of additional broken panels on a recurring basis

2. Pay people to replace thousands of broken panels

3. Shut down highways for utility work to replace thousands of broken panels

4. Design the panels to meet crash safety design considerations that the structures currently in the median were designed to

5. Add additional electrical safety standards unique to a panel array that designed to withstand car crashes.

Really, this is complete silliness.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#199

Post by ganzuul »

lgats wrote: post #190
nostoc wrote: post #180

Earlier quoted context omitted.

No, a blue filter, like a blue plastic bag would let blue pass and absorbe the other colors. That's why if you shine a white light through a blue filter, things look blue on the other side. Now, some of the blue light is scattered away, and that's why you see the plastic bag itself as blue.

Imagine looking at this blue-transparent bag with a red light, it will appear more opaque.

Just like laser light protection goggles.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#200

Post by lxmorj »

Polylactic_acid wrote: post #185
tsimionescu wrote: post #158

Earlier quoted context omitted.

Algae in the ocean, mostly. But also, any growing plants - you could compute for every kg of dry plant matter, how much oxygen is released, as the dry plant matter is almost entirely carbon produced from breaking up CO2. So unless you're collecting tens or hundreds of kilograms of dead plants from your roof every year, it isn't producing much oxygen.

This is why we won't solve climate change by simply planting trees. Planting trees is good but once the land is covered in trees like it was you can't go further. You have to start actively putting carbon underground so it doesn't end up in the air again.

Well, you can build shit with the wood that's going to last a long time and plant a new tree. Though I'm not sure the lumber processing & construction isn't producing more carbon than the tree sequesters...
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