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Semi-transparent, colored cadmium telluride photovoltaic panels in agrivoltaics

https://www.anthropocenemagazine.org/2026/10/magenta-solar-panels-may-be-agrivoltaics-cleverest-trick-yet/
Specialty cut flower grower here. Backyard scale, but we're profitable and have received some grants so that means we have had a USDA relationship for a couple years. The rep I've talked to and am closest with is skeptical of agrivoltaics due to past dealings with solar companies (not sure what she means). There doesn't seem to be enough reliable public data to make it seem like the win-win-win we want it to be. In their mind, you're adding a non-ag industry to the land and that could have downstream consequences in a generation. Maybe you're scheming to get the land re-zoned for light industrial; I honestly have no idea what they're thinking, but they're averse toward it.

Most flowers in 7b don't want extreme sun. We use shade cloth frequently, so solar coverage would be fine and of course have the energy co-production. Cut flowers aren't harvested mechanically at our scale, so we wouldn't have to worry about tractor access.

Meanwhile, more and more food is produced under cover for a lot of good reasons. Polytunnels, glass houses. You might get some summer shade from solar but what about season extension at the beginning of spring/end of fall? Depending on your crop and location, that could mean 4-8 extra weeks a year. What if you do geothermal energy generation for the tunnel? Now you can grow through the winter and not need the same footprint as solar. That's more appealing to me.

Anyway, I'm forever mad at corn ethanol and we should at least replace all that with solar farms. That's probably the right place to start. But also, again, zoning...

Completely off topic but I'm fascinated with this. How much acreage do you devote to this?

I've done hobbyist exotic (legal!) mushroom farming for a while, at a scale that is more than I could use but not like 100x what I could use. I've thought about selling but it seems like a lot of hassle doing the marketing and business parts of it.

How do you sell? Do you have a distributor that purchases product from you or is it a farmers market type deal?

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TIL: 7b refers to USDA Plant Hardiness Zone 7b, a climate classification used in the US to indicate the average annual extreme minimum winter temperature.

Zone 7b: −15 to −12.2 °C

Zone 7a: −17.8 to −15 °C

Zone 8a: −12.2 to −9.4 °C

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Would also love to hear more about your project!
Very conservatively solar produces 30-50 times are much energy per acre as corn ethanol. I think if you consider just the ethanol to mix with gas vs charging an electric car with solar it's a 100 times more.

Something around 2500W of solar can provide enough energy to drive an EV 12,000 miles a year.

When it comes to zoning. The state should require offices to install chargers for employees cars when the solar share of electricity generation is highest.

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> Meanwhile, more and more food is produced under cover for a lot of good reasons.

(Disclaimer: I know nothing about farming)

I somewhat agree - dumping pesticides and fertilizer into the ground every year and then letting it pollute rivers is low-key insanity. But then you look at just how much farmland is out there and realize some crops just can't be put indoors, probably ever.

There are lots of variables for sure, but I do wonder how much more efficient indoor growing must get to overcome outdoor growing? Land value is vastly different between regions, so does labour, crop type, etc.

p.s. Tom Scotts recent video on strawberries was amazing - special mites to fend off other bugs and UVC light sanitizing was a bit of wow for me.

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HN is probably over-indexed on people living in high-density cities, which might explain why tech like this and also things like vertical farming are popular here. However there's almost no dimensional constraint for farmland in the United States. We have vast amounts of it and there's really nothing to be gained from "stacking"

Often these "solutions" introduce more problems than they solve. One example being a solar farm designed to be grazed by sheep where the panels are so low to the ground that farmers can't bring in tractors and cut hay when the ruminants are gone for a season.

The best solution is still to put solar panels and farmland in different places where each can be optimized without concern for the other.

> The best solution is still to put solar panels and farmland in different places where each can be optimized without concern for the other.

There's significant evidence "add solar panels" is an optimization to at least some kinds of farmland.

> farmers can't bring in tractors and cut hay when the ruminants are gone for a season

That season is typically "winter", and you wind up without much hay to cut at that point.

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The case the article makes is for “devoting 1% of farmland to agrovoltaics”, that seems arguably very low and non-intrusive. The loss of some micronutrients is more worrying than the cute notion that industrial-scale farming bothers with sheep grazing.

We could grow some crops in that 1% of land and provide reams of clean power to the world. And the more we restore land to nature, as opposed to our mono-crops and cows, the more co-benefits we reap.

This need not work for all farmland to be useful.

As an example where I think it would work: industrial greenhouses.

Why should the tractor be a 1950s tractor pulling a mower attachment? If we are talking about something so techy as a solar panel clad farm, it is definitely going to have electronic robotic mowers. These are already used in commercial landscape setting and barely 2 feet tall.
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This makes sense, as there have been quite a few VC-backed vertical farming (mostly for vegetables, as you can’t grow grains AFAIK) startups which have shut down in the recent few years.
> cut hay when the ruminants are gone for a season.

But surely only certain places need to do this? for the UK, you need to make hay for the winter, assuming that your meadows flood, or are otherwise muddy. But if your in one of the more temperate areas of the southern USA, surely you don't need to do that?

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Huge isolated fields of solar end up with the same problem as nuclear: they introduce multiple single-points of failure.

The source can be attacked, the transmission infra can be attacked, the delivery point can be censored.

I think most people want highly distributed, reliable, affordable power. That's why off-grid tech is experiencing such a boom.

I live in a 36' skoolie, so I'm nomad-indexed, but I can confirm that over the past 10 years or so, most RV-lifers have transitioned their focus from recreation / comfort to off-grid experimentation. Essentially everywhere I go in the US, if I'm camped near others, they are going to have minimum viability for boondocking. That was not the case when I started.

Especially amidst the current political instability and apparent looming collapse of the US state, one of the simplest things that most of us can do is stabilize off-grid power in our neighborhoods, and that is quietly happening all over the place.

So, the role of vertically integrated solar (both literally and metaphorically) has more to do with the grid shape that serves our stability needs, and less to do with large-scale differences in efficiency.

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Some of us are interested in ways to do things outside the US. Yes, even some who live in the US.
You know there's a whole world outside the US... AND most places do not in fact have those vast amounts of open land
In the theorical sense, sure. We could cover all of the world's needs with a solar panel in the Sahara that's 700 km on each side and handwave the transmission lines for that.

The real world however, a farmer owns a specific plot of land, has $w of capital in the back, owes $x in loans, owes y tons of crop, owns z tractors and seeds. Without centralized planning, plopping down solar panels in an optimal place isn't how the real world works.

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surely someone is busy breeding the tastiest salad that just can't survive being transported for more than 30mins so you end up NEEDING that stacking right in the city where all the michelin star restaurants are... get the rich to fund and perfect the tech, as "green" as it can be, get some patent under your belt for your investor (mars garden anyone?)
In the theorical sense, sure. We could cover all of the world's needs with a solar panel in the Sahara that's 700 km on each side and handwave the transmission lines for that.

The real world however, a farmer owns a specific plot of land, has $w of capital in the back, owes $x in loans, owes y tons of crop, owns z tractors and seeds. Without centralized planning, plopping down solar panels in an optimal place isn't how things work.

> The best solution is

is it?

if your initial reaction is we have tons of empty land why would we ever build solar panels over a farm?

this isn’t an either-or question. a farm owner may want to add some revenue with electricity generation. just like a hospital may want to cover their parking lot to offset costs.

at giant scale do these solar location choices optimize the absolutely best use of land for cheapest possible electricity generation? no. but at small scale it can make sense for these individual owners

https://electrek.co/2026/10/05/six-flags-has-installed-one-o...

I believe that, while a cool technological innovation, the cost of installing and maintaining these panels will be significantly higher than doing the same on open land.

The article’s biggest claim is that devoting one percent of US farmland to agrivoltaics could cover 20 percent of the country’s electricity, pointing at the Texas to Nebraska to California corridor, which is exactly where big mechanized farms are most common.

They run large equipment (combines, sprayer booms, center pivot irrigation systems[1], etc). To keep that working under panels you need tall posts, wide spans, and a layout that matches the equipment paths, which would push structural cost significantly above a ground installation. All maintenance would require a boom truck, not just a ground crew. And center pivots in particular (very common) need an entire circle cleared for the system to pivot, meaning a multi-acre span with no posts for the pivot to hit, which is simply infeasible.

That’s before accounting for pesticide spray and dust on the PVs, or the logistical burden of running PV crews through a working farm.

It’s also worth noting that the study itself was broccoli, which is hand harvested and about the best case crop for this. Even so, the broccoli took 25 extra days to mature. On a farm running multiple rotations a season that lost time has a real cost, separate from the structural costs.

This innovation has a lot more promise on smaller plots. Co-ops, market gardens, specialty crops, and the like that don’t rely on large equipment. I’d be surprised to ever see it on a large farm.

[1] https://en.wikipedia.org/wiki/Center-pivot_irrigation

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You can farm and do industrial scale solar on the same land. It works extremely well for lamb herds, shade tolerant crops like strawberries, and greenhouses. I'm extremely interested in this area and actually starting some personal projects where I live, around agri-solar that is actually farming.
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Optimization for land area in agriculture is already a catch-22 type affair: We subsidize the planting of corn to produce ethanol -- one of the most inefficient forms of solar energy 'harvesting' possible. So going directly to electrical harvesting while retaining the ability to grow high-value crops is certainly still advantageous...

To put some numbers: ~40% of the corn grown in the US (approx. 5.4 billion bushels out of roughly 14.9 billion bushels total production) goes toward ethanol production

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> this isn’t an either-or question. a farm owner may want to add some revenue with electricity generation.

Also: Many plants don't want/need full sun. In fact, they adapt by varying production of a chemical called zeaxanthin throughout the day to manage the amount of energy they take in.

Partially shading crops with bifacial panels (which are semi-translucent) can be beneficial to the crops as well as producing energy.

https://www.science.org/content/article/too-much-good-thing

Initial reaction is how do you harvest? Is the farm well connected to the grid? Is the cost of making this practical just much higher than land. Land is cheap in the scheme of things here.

https://farmbuy.com/1595-florina-road-katherine-nt-0850-4368...

1% of panel cost according to Gemini.

Sure, but given that a 100 acre corn farm in Ohio would make about $80k in revenue and if you're lucky about $40k in profit

A 100 acre solar plant in Ohio would make well about $1m-$1.5m in revenue

Why would you increase the cost and complexity to try to increase your revenue from $1-1.5m to a massive $1-1.5m?

Or you could just lease the land to a solar operator for about $100k a year, with no expenses

It's a solution looking for a problem.

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little known fact: US currently grows a lot of corn for ethanol production. If we replaced that all with solar panels we'd have plenty of electricity. The solar vs farm debate is usually framed as a tradeoff with food production but that's not really true

https://www.anthropocenemagazine.org/2025/04/new-study-compa...

> The USDA now expects 5.65 billion bushels of corn to be used for ethanol production in 2026-27

> The department has raised its corn production forecast by 234 million bushels to 16 billion bushels.

https://bioenergytimes.com/usda-raises-2026-27-us-corn-use-f...

About a third! Way more than I thought. I wonder how much of that would have to be covered in panels to get the same energy.

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> little known fact

It is well known fact, that US do that so 20% of its population wouldn't die from starvation over the next 30 years with significant probability.

One thing the article doesn't mention is that some plants prefer a little shade.

So while broccoli yields may have "held steady," it's possible they could make even more gains elsewhere where it might normally be too sunny. So leafy vegetables like spinach might be doing equivalently fine under the magenta shades in New Jersey, but might actually be even better in Texas.

They certainly do mention this:

> Broccoli cultivated under them grew more slowly, requiring an additional 25 days for harvest, but produced roughly the same yield. Meanwhile, these magenta sunscreens improved the microclimate below, reducing the “vapor pressure deficit”—a measure of when plants need to halt photosynthesis to avoid excessive water loss. This may have improved the plants’ efficiency in converting sunlight into plant biomass, which increased by 2.8- to 4.5-fold compared to unshaded plants.

> The shaded plants’ levels of macronutrients such as calcium, magnesium, and phosphorus were either higher than or similar to unshaded plants, while levels of some micronutrients such as iron, copper, and zinc were slightly lower.

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I find the physics of wavelength-dependent materials properties oddly satisfying. You can do clever things like this, extracting energy from different parts of the spectrum by combining materials and conversion processes. You can beam waste heat back to space through the atmosphere’s “infrared window”. You can explain global warming from first principles. Fascinating stuff!
One thing I’m curious about this from the plant perspective - we’re pretty sure we’re passing everything relevant down to the plant, but nature doesn’t normally leave signal or energy lying around without leveraging it somewhere, so what don’t we know about how the broccoli use the parts we’ve been assuming they don’t?
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I feel the same way about how fiber optics can create bandwidth by just slicing up the spectrum for different channels of data (my rudimentary understanding anyway). I like how even after all this time we find new and clever ways to work with light.
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Wavelength-division multiplexing[1]... it's what they use with fiber-to-the-home to get bidirectional signals with a single strand of fiber. Or the big-boy version is DWDM which ISPs use to stuff dozens of customers on a single strand.

You might also be interested in https://phys.org/news/2026-11-air-holes-silicon-wafers-flat....

[1] https://en.wikipedia.org/wiki/Wavelength-division_multiplexi...

I'm current taking composite construction certification courses because modern manufacturing provides for customizing the material for very specific uses. Low volume production with very specific mechanical and physical properties.
Wait we could reflect back infrared heat into space and still collect solar energy as electricity - so doing two jobs at once in, say, a desert.

Re-greening at a profit?

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Are there realistic ways of harvesting vegetables at scale that are underneath mounted solar panels, with all their supports?

Or is the idea that there aren't now, but they could be built?

I'm just imagining that you are going to need a lot of vertical clearance for tractors, and support posts will have to be widely spaced enough that the horizontal beams supporting the panels will have to be quite strong, and that at some point this is less solar panels in a field, and more like constructing a building with solar panels on its roof.

> Or is the idea that there aren't now, but they could be built?

It's hard to see how this would work well with corn, since corn is pretty tall, corn harvesters are pretty huge, and putting panels even high enough for a different set of smaller, realistic harvesters would still require supports that I can't imagine would be cost effective given all the other hurdles they would cause.

Other crops like cotton, alfalfa, and hay aren't as tall, but have the same harvesting problems.

Most harvesting efficiency gains are directly tied to GIGANTIC machines. Farming is insanely efficient and competitive. It's hard to see how smaller machines could be viable and no one would have discovered it until this tech.

I'd guess there is far more potential in grazing land (unrelated to this tech), which is already actively being developed at scale.

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You can see there are already huge examples of this in Australia with sheep grazing under panels and it's just barely starting in New York state with a cornell pilot. In my opinion it's the future of electricity in agricultural areas.
Smaller scale market gardens could benefit. Many rely on more manual labor and smaller machines.

There are some small organic farms using a system of chained paper pots and frames to quickly fill them with soil and sow with seeds, then once they're sprouted you use a hand pulled machine that spreads the chain out while directly placing each plant into the soil automatically.

Depends on what the crop is. Broccoli I imagine, is manually cut. same with tomatoes.
CdTe panels are limited by availability of tellurium. Maybe we'll mine that in space one day; much of the Earth's Te was lost as volatile H2Te. The abundance of Te in carbonaceous chondrites is about 1000x that in the Earth's crust.
Given that it's about as abundant as platinum (which trades at ~$50000/kg), tellurium is pretty cheap right now (~120$/kg, about 10 times the price of copper).

Since it's an almost free byproduct of copper electrorefining (>1% concentration in copper anode slime, but low annual production of ~800 tons, limiting CdTe panel production to ~100GW/year short term [1]), I don't think that mining it in space is ever gonna pay off for terrestrial panel production, because if it was priced somewhat comparably to platinum group metals you could never ever justify any demand for it (panels would be much too expensive compared to alternatives, tellurium is already a relevant cost factor for them despite being cheap-ish) => and you'd obviously use all interplanetary mining/transport capability on platinum and its ilk instead.

[1]: https://www.pv-magazine.com/2026/02/10/global-cadmium-tellur...

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There's the minor issue in that the technology to bring all that metal back home is also a weapon of mass destruction :-/
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I'd love this for a home greenhouse... I live in an area where during the summer insolation is high enough that some combination of large amounts shading and airflow (wasting humidity) is needed... wavelength-selective shading seems like an interesting idea to start with, and energy recovery from it is a nice add-on.
For a larger greenhouse a mix of clear non solar and solar pv pannels optimised for different plants could be the way to go. The polycarbonate clear pannels are actualy cheap and likely strong enough that I am considering mounting solar pv directly to them. So: scratch building a greenhouse frame, that will support all the loads, and attaching the panels, and run the wires right through the polycarb, standard solar pannels, install@40" width and that works out to 3 per 12', 12 pannels for 40', for a neat eve to eve install.
The only real problem with this becoming common practice? The very first question and assumption of needing a solution.

>Vegetable farms and solar farms both need lots of sunlight and open space. But how do we divide our limited lands between these two priorities?

We are in no way limited by farmland space. Farmland utilization has been dropping since WWI thanks to the invention of artificial fertilizer, and even without artificial fertilizer at current population levels we would have never ran out of farmland although there would be a lot more of it. All across the midwest you will find tracks of land that use to be farmland, but is now either overgrown with trees, grass, or shrubs and completely unutilized for any human purposes. And our main limitation to growing even more food if we wanted a bunch extra for some reason would be fertilizer production/energy, not land space.

This is great science and knowledge, but I don't expect anything useful coming from it for farming on earth. There is no shortage of dirt that the sun shines on now or anytime soon, and no matter how efficient your panels, plants, or extra lights are, the sun is free and a greenhouse is way cheaper than anything else you could possibly build.

Sure, all the solar power for the US could come from Australia.

Meanwhile, when planning and streamlining infrastructure for cities and large urban centres some do look to guidelines such as minimising transportation (food into cities, refuse out, etc) and transmission line costs.

Food production has water, sunlight, fertiliser etc. requirements, energy generation (solar, wind, coal, oil, gas) similarly has geolocation (sunlight for solar, temperature differentials for wind, mine / port access for solid fuels, pipelines and tanks for gas) requirements.

Urban planners also look to stability of supplies and robustness of systems (if X fails, what do we fall back on).

These are the manner of things that can put dual use demands on various parts of the ring about large urban areas.

There are countless square miles of vacant land in the USA that are unsuitable for farming and ideal for solar. This might be useful in areas where vacant land is actually scarce.
The US is huge. The problem is efficiency of transmission. But maybe we just install 2x the solar to overcome that? When energy is so low cost we can afford to be a bit less efficient.
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A huge amount of corn goes into producing ethanol to burn as fuel in cars. We can safely take a small portion of agricultural land out of "food" production and replace it with photovoltaics and electrical production instead of using it to produce ethanol and produce productive stable returns for farmers instead of subsiding corn and fuel.
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That vacant land tends to be far away from electricity users. Not always - lots of desert around Las Vegas - but people historically like settling around arable land. Producing electricity close to where you need it is great, both because of transmission losses and because building more long-distance transmission lines is neither easy, cheap nor fast
I feel like starting with parking lots might be better than filling "empty" land though?
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The better solution to this vacant land is to remove the regulatory and permitting burden that made it vacant in the first place.

Let the people build.

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Wild, I did a science fair experiment on plant growth vs light color as a young kid! i had each plant in a different shade of upside down tumbler cup and compared the growth. N=1 for each cup, but I remember being surprised that the plants really didn’t seem to care when you filtered out certain shades.
I really wouldn't want anything containing cadmium near a farm field.
What could possibly go wrong?
Material Science Gameplay Loop

1. Development Miracle Substance

2. Try to replicate the properties without Cadmium, Mercury, Arsenic, and Lead

3. Figure out how to scale production

4. Congratulations you're selling the material, but 6 months ago another team had a break through, so the loop resets.

Man I’d buy and install these in a heartbeat. My suburban house has a couple of small areas that would be perfect for a greenhouse that produces electricity
I like the idea of hybridizing the solar infrastructure to work with advanced AG systems. I watched a recent tour of a modern strawberry farm, and I was surprised that they were using wheeled robots instead of overhead tracks.

https://www.youtube.com/watch?v=TumxO2glmPQ

I especially like how this could reduce the need for irrigation in dryer climates.
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Literal children of the magenta.
This is WAY more interesting than SpaceX launch number yada yada or whatever.

Datacenters in space are for Elon & his stock price, nothing more. Meanwhile we are not prioritizing things like this nearly enough. Solar on earth is what needs to be rolled out in a massive way, for our current energy needs and for datacenters.

Theory is always more interesting than practice, because theory never has to make money.

Remember spacex is a public company and you can short the company at any time if you believe what you're saying. Why not profit off it?

I think the question is, are these panels less expensive than taking normal panels, maybe with LEDs to help growth at night, and adding solar tracking to optimize solar generation, plant shading, and plant growth?
Economics would suggest full spectrum panels on the outside + LED-lights on the right spectrum on the inside will always be more affordable than specialized panels. You still need lights with magenta panels to hit 18+hrs of light a day. Once the lights are already installed, specialized panels would be hard to justify a mark-up.
> Economics would suggest full spectrum panels on the outside + LED-lights on the right spectrum on the inside will always be more affordable than specialized panels.

Lookup the energy needs to grow plants, panels are like 25% efficient, you'd need to put most of it back into the LEDs to grow anything. Growing LEDs aren't your regular 5w home light bulbs, you need a lot of energy to grow plants.

This is the classic out of depth HN take

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