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Growing crops under solar panels (fastcompany.com)
152 points by lxm on March 10, 2023 | hide | past | favorite | 149 comments


There are interesting things in the article, but I think it was never about available land use, but just another knee jerk argument against solar panels.

Example: Disneyland Europe will generate over 30 GWh per year from just covering a part of its parking lot. And if France makes it mandatory to cover all "substantial" parking lots it will generate as much electricity from just that as 10 nuclear power plants [1].

And that's France. Countries like the US have a lot more space, especially parking lots. There's enough space for solar panels.

[1] https://www.washingtonpost.com/climate-solutions/2023/02/06/...


As someone in Texas I'd really love is more parking lots had even partial covered parking with solar above. Please. It gets dang hot out here, I'd love the shade.


I tried to sell this in Texas a decade or so ago and feedback from most tenants and commercial RE folks was they were concerned with lighting, visibility , safety (as in, increase opportunities for theft/assault), liability, etc of having panels on their property. All I wanted was the use of their land and I was going to fund everything else. Likely would have pursued selling them low rate electricity. The market wasn’t ready for it at that time.


So you were thinking about doing a million dollar solar install, but you couldn’t come up with $10k for land to do the install?


He didn't say he wanted to do a "million dollar solar install" and he certainly didn't say he couldn't come up with "$10k for land".


This. I also only mentioned that part because “selling” was really “convincing” as I wasn’t asking for any money from them. Only a partnership. My early assumption was they’d be receptive to it because shade would be a big boost to comfort and I’d get free use of land though a mutually beneficial arrangement.

This was a long time ago so I don’t actually even remember what my ultimate business strategy was, only that I talked to over 100 different companies/property owners and got overwhelming unreceptive feedback (that they didn’t care about shading their parking lots) so that was the extent of my interest in chasing the opportunity. I don’t think $10k would secure much land at all. Even back then, maybe 1 acre 200 miles away from a city. That wasn’t economically feasible back then. I think it’s only recently becoming so and some “solar farms” are popping up. I’ve moved on and don’t follow it much anymore.


shoot, around my parts of Texas, when you stand in the shade of a tree, the tree looks at you and says, "trust me, it's not any cooler here"


Shade under a solar panel is cooler than normal shade because the panel is siphoning energy away from the location


You have trees?!?


well, they are Mesquite bushes, but it's got leaves, grows from the ground, produces wood, and makes a bit of shade, therefore...tree.


And another reason why I think residential solar is so key, right now it takes a backseat in policy to gridscale, which ... ok the US has a lot of land (allegedly), but using commercial roofs and parking lots is a lot closer to residential solar issues than gridscale in the middle of nowhere: there's a lot of variety in geometry, installation headaches, hookups, distributed management, repair.

Ultimately it means more jobs, more civilization resiliency in disasters, and a "democraticization" of energy generation, which I think the elite REALLY don't want.

It's a thing that economic development basically follows energy production. Central control of economic development (which is what we have with cartel megacorps) wants centralized control of energy production.

Solar isn't just a good carbon policy, or a path to cheaper better energy, or better insurance/life in unstable grids. Home solar is an improvement to individual or small-group liberty.


It’s not some “elite” cabal. It’s transparently the utility companies and adjacent industries. They fight this unless subsidies for their “increased costs to the grid” are covered. It seems in local areas I’ve seen this play out it always comes down to the fact they want the public to pay for the grid upgrades they should’ve been doing in the first place.

I think from what I’ve read online and heard from others this is a pretty common if not nearly universal thing happening when it comes to the pushback against rolling out residential / urban solar at scale


> And if France makes it mandatory to cover all "substantial" parking lots it will generate as much electricity from just that as 10 nuclear power plants [1].

It will not, not even close to that. You are being deceived. This deception is willful, because it is obvious to anyone who has any idea about realities of energy generation. The linked article, however, while not literally lying, omits some obvious facts, the goal of which is to make you believe falsehoods.

The article talks about "installed capacity", and compares installed capacity of photovoltaics vs. nuclear power plants. It is extremely deceptive to make such comparison without taking into account the notion of capacity factor, and the proof of this is that you have successfully been deceived.

The nuclear power plants typically generate north of 90% of their installed capacity, averaged over the entire year. The photovoltaics in Europe, on the other hand, typically generate 10-15% of their installed capacity, averaged over the entire year. This is caused by the unfortunate fact which is that the sun doesn't shine at all for at least half of the year, and for the significant part of the remainder, it is occluded by clouds, or shines at suboptimal angle, preventing the panels from reaching their maximum generating capacity.

This means that 1 GW of installed nuclear power capacity is worth at best something like 6-9 GW of installed photovoltaic capacity. At best, because photovoltaic generation will mostly happen on summer days, resulting in excess supply and so low value of generated energy. In winter, when photovoltaics generate relatively little energy, and the energy demand is high due to heating needs (especially during the night), the value of 1 GW of produced nuclear power will be higher than value of 1 GW of produced photovoltaic in summer.

The result of this is that covering half of all parking lots in France with photovoltaics is effectively worth less than a single nuclear reactor. This is obvious to anyone who pays even minimum attention to the economics of energy production, but the activist-media complex works very hard to deceive the public, leading them to believe that photovoltaics are already cheaper than fossil fuels and nuclear power. They are not, not even close, and this is even ignoring how nuclear power in France subsidizes solar/wind in a deliberate, systemic way.


What makes you think they didn't already take that into account? There are really an awful lot of parking places.

Also, the panels will give electricity at the same times we are going to want airco due to global warming, so at least it helps to cover that need.


Never trust a reporter to be numerate. Never trust a press release, ever.


Don't trust anybody, not even yourself.


That's an awful lot of vitriolic words to express: comparing kW and kWp is a type error.

> This is caused by the unfortunate fact which is that the sun doesn't shine at all for at least half of the year

And factually incorrect. Currently sitting in Northern Europe making 5.05kW from a 5.6kWp installation.


... Currently. And average ?


Obviously it is quite seasonal. In February we generated 350kWh or 12.5kWh per day average, importing 13.2kWh in total and exporting 153kWh. In January it was 8.5kWh per day average.


Good thing that wind power is stronger in the winter, thus complementary to solar energy.

> They are not, not even close, and this is even ignoring how nuclear power in France subsidizes solar/wind in a deliberate, systemic way.

Source? Do you also want to tell us about the subsidiaries of nuclear energy in France?


And of course the main way nuclear got help more from subsidies is the huge early amounts of taxpayer funds poured into its R&D and military use since the 40s - if wind and solar had gotten even half of that, renewables would be decades further along and further down the cost curve by now.


You're making a case against solar panels but that is not what my comment was about. If they're worthless they're worthless, but there's more than enough space for them.


> the sun doesn't shine at all for at least half of the year

Hyperbole much? The polar night is a lot further north.


No, I am talking about regular night, which adds up to half of the year.


I’m no farmer but wouldn’t putting a whole bunch of stuff in a field make it difficult to drive a tractor through it? Like have you seen the size of modern tractors? These panels will need to be 20ft in the air with support posts really far apart to accommodate seed drills and sprayers and other equipment that the tractor pulls behind it.


To some extent that falls into the category of "fiddly details." Solar panels are probably not the best choice for use alongside bulk harvested crops like corn, wheat, soybeans and even potatoes, but an awful lot of "produce" crops are harvested by hand.

The reason I say "fiddly details" is because questions like "what's the best spacing between rows of panels" and "do I plant under the panels or just between rows" can be decided as people look into available equipment, land prices, crop variation and flexibility, etc.


I don't know about "growing crops", but a farm outside the city where I live has sheep grazing under/around solar panels.


Heck yes.

It's absurd now but... imagine those crop-water-er things, with a central pivot (ed: "central-pivot-irrigation").

What if instead of just a line of watering, that rotated around, it was a vast overhead rotating circle? Like 80% by area solar panels overhanigng. But also, one radian with all the farm stuff: watering, tiller, planter, harvester? An polar-plotter of tools, with solar panels taking up most everywhere else.


I’m actually experimenting with building one of those- the problem is the forces involved compared to the irrigator which is basically just suspending water pipes over the ground


maybe i'm misremembering, but I was under them impression that the water pressure drove the platform. was i totally wrong on this? i ask, as i would never have guessed adding the weight of solar panels to that would be viable without possibly using some of the generated power to drive a motor.


Early systems were driven by water pressure. Modern systems have an electric motor for each pair of wheels.


Picture of sheep grazing under panels in Australia:

Solar farm trial shows improved fleece on merino sheep grazed under panels

https://www.abc.net.au/news/rural/2022-05-30/solar-farm-graz...

Note the room to drive between panel rows and for "boom mowers" to spread out behind a medium tractor and reach under the panels.

There are also many types of vehicles used in agriculture from two storey high broad acre heavy duty combine harvesting monsters to small narrow self propelled engines that run through tree trunks in orchard with various attachments to mow (sprung mowing rings), shake trees (to make fruit fall), spray leaves, trench (for irrigation, drainage, etc).

Also, see: "Agri-bots" - a revolution not yet complete in small driverless autonomous helpers to run 24/7 weeding, spraying, picking berries, using solar, etc.


>improved fleece on merino sheep grazed under panels

Makes sense. I'm not sure the exact care instructions, but I'm pretty sure "store this garment outside unshielded in the baking sun and pouring rain for many months" isn't the official recommendation for wool.

If available, sheep (and other animals) will seek cover during heavy rains and periods of high heat stress. This protects both the sheep and the wool, and both factors improve quality.

I wouldn't be surprised if the diet improves as well, due to healthier grass, higher plant biodiversity, and higher abundance of (tasty and nutritious) insects.

Paradoxically, primary productivity will often increase with added shade, because photosynthesis shuts down at even mildly elevated leaf temperatures (~85 °F). Those vast impressive corn fields will often overheat and shut down around 10 AM, and don't start photosynthesizing again until 4 PM.

In ye olden days farmers would plant a widely-spaced grid of "farmer's trees."[0] These are a category of trees (eg black locust) which 1) provided shade and windbreak, 2) coexist with crops right up to their trunk, 3) have deep tap roots bringing up minerals and water, 4) drops fertilizing mulch, and 5) produces nutritious animal fodder (pods) which self-dry and store on the tree itself. Clever farmers!

For mechanized farms you can choose a planting pattern and varieties that permit machinery to drive right past the tree without losing much area on "gores." Typical density was about 20-30 trees per hectare, so it also stores a bit of carbon.

Personally I prefer trees, but ultimately we need both types of systems.

[0] https://www.youtube.com/watch?t=25&v=uvQpIHBSPBE


Wool has a protective layer of grease, the same thing that makes your hair feels "greasy" if you don't wash your hair for a month. This grease is washed away during wool processing and sold as lanolin.

And also, the degradation that you see on sun-damaged clothing is mostly on the dye, not the underlying fabric itself.


> Wool has a protective layer of grease

Right, it's called lanolin.

It's also true that lanolin + shade and rain cover is better than lanolin alone. No protection is 100%.

> degradation that you see on sun-damaged clothing is mostly on the dye

"Mostly." We agree damage is done to the fiber. ;)

By design, modern dyes often act to protect fibers, soaking up energetic photons before they can damage the fibers themselves. In their absence, undyed fibers can be more susceptible to damage.


> the degradation that you see on sun-damaged clothing is mostly on the dye, not the underlying fabric itself.

UV light will absolutely wreck most things, including fabric. Fabric left outdoors unprotected for a summer in Southwest US will be brittle and tear apart when handled. Plastic that isn't UV-protected will crack in about two summers. Hoses left in the sun will develop multiple leaks in 3-5 years, pretty much no matter how robust the marketing claimed they are.


Be careful with the distinction between synthetic materials and natural ones, they do not react to UV the same way.


Why did the sheep not already have access to a shed or other form of shelter from the sun/rain?


There are some 68 million+ sheep in Australia and the barely 25 million people are facing a housing shortage ATM .. there's never been sheds and houses for sheep in Australia aside from shearing sheds that only see once per annum usage.

As you can see here [1-4] paddocks have trees, dams, etc.

[1] https://www.youtube.com/watch?v=Fi4FvVqMnBk

[2] https://www.youtube.com/watch?v=Y5RIqsac2Hs

[3] https://www.youtube.com/watch?v=McNSfo38DYI

[4] https://www.youtube.com/watch?v=S3SYMPabyT0


I had been assuming that even if there was not a shed, there would be ample trees for the animals to take shelter when needed. Wild to me that providing shade had been neglected by the shepherd.


There's no profit to be had in giving shade to the sheep.


Vertical bifacial panels are one approach that doesn't interfere with tractors and equipment, and still have comparable generation (with twice as many panels, so more expensive):

https://www.pv-magazine.com/2023/01/24/vertical-pv-for-clean...

> "For conventional ground-mounted systems, the scientists considered a tilt angle of 20 degrees and an average estimated energy yield 1,020 Wh/W. For the bifacial vertical west-east oriented systems, they assumed a bifaciality factor of 90% and an annual energy yield of 999 Wh/W, while for vertical systems with a north-south orientation the annual energy yield was indicated at 926 Wh/W."


Vertical orientation can also make sense if you're trying to bias the PV to produce more in winter, when the output might be more valuable.


Yes, I think a single picture of a farm setup this way would have increased the value of this article quite a bit.


This[0] is a berry farm I was just at. As you can see it’s already covered to protect from extra sun. No tractor could fit anyways.

This[1] is one version of agrovoltaics. The solar panels act like window blinds. They can be configured to follow the sun but also can be configured to “provide optimal shade/cooling throughout the day”.

[0] https://images.app.goo.gl/mSbtJjtSQRukBQqK6

[1] https://images.app.goo.gl/9kakPW8uRHLGp3yJA


"This[0] is a berry farm I was just at. As you can see it’s already covered to protect from extra sun."

Erm, I can see a greenhouse. I think they are made to increase temperature for the plants and not to protect from extra sun. Strawberries like sun and would not benefit from shade, unless we are talking about very intense sunlight and not much water.

Most plants usually want as much sun as they can get, so long as the temperature stays in their desired range and enough water is avaiable. So in dry places with lots of sun, acrovoltaics can make some sense, or for plants that like indeed shade, like tomatoes. But it is really not a magic bullet for growing corn and harvesting electricity at the same time.

Sheeps grazing under solar panels seems like a working solution that does not need too much effort around it.


A lot of plants doesn't like and cannot survive the sun at central hours unless you water them like crazy. Basically you are watering to avoid dehydration, but not producing, like drinking in the desert. A lot of plants evolved to thrive near/under trees.

Greenhouses can tame the sunlight, and usually they are painted in white in regions of too much sun (https://m.youtube.com/watch?v=Rl6tMOU84tk). Also, greenhouses are hot but very humid, so the plants doesn't dehydrate as fast.

I could imagine an scheme that instead of watering (costs money) you shade the crops with panels (earns money) during the worst of the day.


I live in the hot and humid Deep South and my strawberries do not mind the sun. There’s a local berry patch that has lots of different berries, including strawberries, and no shades in sight.

What’s in OPs image is a greenhouse. The sides can be closed if low temperatures are coming in at night.


The examples given in the article are mushrooms and broccoli. Obviously the primary and first use cases would be things that want some shade (in the local environment).


Most of the examples I’ve seen are small scale hand pick farming. But there is nothing about 20’ spans that are outside our technical abilities today. This seems like a rather small obstacle to overcome. Of course this still says nothing about the economic feasibility or impacts.

Thinking more about it, you wouldn’t even need 20’ spans. You’d have articulating struts coming off of a central point between the rows. Panels can be adjusted out of the way of equipment when it needs to pass through if it is interfering.


The crops that are best suited to giant tractors also tend to be less suited to agrivoltaics.

They also include energy crops, so you can go from producing no food on land with unprofitable crops that take subsidies to growing food on the land at a profit and producing energy.

The land taken up by energy crops exceeds the land needed by solar by over an order of magnitude.


there's no reason to put solar panels on fertile land, there is plenty of land that can be used in other places.


Solar panels are already being put on fertile land (in UK), so if that land can get dual-use and not waste it's potential for food provision then that seems more optimal.

That said, these threads always confirm in me a belief that we need to cut human population replacement to save the planet and our own species.


I can tell you are no farmer. No tractor is needed in a field maintained by grazing. If tbe panels are mounted high enough sunlight will be cast on the ground for a period each day.


I am a farmer, and this doesn't make sense. Grazing fields aren't really growing crops.

Even if this is just crops that are picked by hand (it mentions broccoli), they typically still have huge machines follow the laborers for them to deposit them in: https://www.youtube.com/watch?v=bKyxMKO2kyU

I can't see any good way to harvest a field with solar panels that isn't so inefficiently laid out that it would be better to have two separate fields.


I am not a farmer, but am interested in watching the development of agricultural tech.

>> I can't see any good way to harvest a field with solar panels that isn't so inefficiently laid out that it would be better to have two separate fields.

Would there be scope for smaller autonomous machines? Presumably, there should be some crop configurations that could benefit, but we don't yet have all the results of experiments currently running. Here in Japan, farms are typically much smaller, so there's perhaps greater scope for agrivoltaics than in industrial scale farms in USA.


Yes a Beowolf cluster could definitely harvest crops.


>Grazing fields aren't really growing crops.

Right, they grow food for animals, which walk around the field and graze on it autonomously. Hey, I wonder if that's why they're called that... :)

I'm not really sure what the point is in making this observation. Just a "farmer vs rancher" thing, or something deeper?

>I can't see any good way to harvest a field with solar panels

See above.


Pastures used for grazing are managed intensively using big machines. (Source: I live next door to a large dairy farm. Pastures irrigated with centre-pivot systems.) Pastures get replanted/supplemental sowing every so often, weeds get sprayed with herbicides, fields get mowed to maintain uniform growth after they've been grazed...


Pastures requiring machinery is the exception not the rule. I can’t figure out what your neighbor is doing.


Factory-farming dairy. Nothing at all unusual. If you have some bucolic vision of cows peacefully grazing all day, being led to a milking shed twice a day, flies buzzing in the sunshine... disabuse yourself of the illusion. When people say "factory-farming" they mean something far closer to "factory" than "farm". To keep cows at maximum productivity, dairy farmers (others farmers, too, I'm certain!) are squeezing the maximum productivity out of their pastures, and that means working them intensively; constant management = plenty of machinery.

I can't for the life of me imagine how these operations are going to continue to produce at these levels without the fossil-fuel subsidy they depend on completely.


I grew up in Pennsylvania Dutch country so rich with cows that Milton Hershey located his chocolate company nearby. I grew up on over 100 acres of that same farmland doing farming things. My Dad in Florida used was a member of the National Cattle Man's Association. I feel grounded in views of farming and acknowledge that my experience has nothing to do with factory farms. Frankly I'm a little embarrassed by the brain power exerted on this thread. I have been a member of both Future Farmers of America, and 4-H.


I really don't get why people keep coming up with all these elaborate plans to mix solar panels with other stuff that's in active use, instead of just putting fields of them out in non-endangered desert elevated enough off the ground that they won't actively interfere with local animals.


Long-distance energy transmission may be technically or politically harder, or just someone else's problem.

If you're a farmer and already own the land, that's what you can do. A combination of the two land uses might be more profitable or less financially volatile than either one alone.


Why would we destroy pristine desert, which is rapidly disappearing, when we could cover land that has already been disturbed, like parking lots, building roofs, and farmland? Deserts are important ecosystems regardless of their immediate utility to industrial society


> Deserts are important ecosystem

Are you using "important" to say "have a function beyond being inert matter"? Then sure, but that information is already conveyed by saying "it's an ecosystem", adding that kind of "important" doesn't add information. If you mean "rank above many other things in a similar category" then I'm skeptical.

The first one isn't helpful in this context because we need to put PV somewhere, we might as well look for a place of less relative importance.


> The first one isn't helpful in this context because we need to put PV somewhere, we might as well look for a place of less relative importance.

Yes, like the places I mentioned in my comment


Installing in deserts means you need minimal mechanical support for the panels. Parking lots require raised ones. Individual roofs are small compared to large solar farms. Most farming isn't compatible with panels (think tractors and harvesters).

That it works for some fraction doesn't mean it's sufficient to get us the terawatts we need. And economics matter. If the installation is more expensive then it'll take longer for PV to replace existing plants.


So essentially you are saying we should destroy the environment because it appears to be cheaper in the short term? Sounds like a classic 20th century trapping that might not age so well when the externalities come back and demand repayment.

I wouldn't underestimate the power of distributed arrays either. There are estimates that if every house had rooftop solar, it would generate 30-40% of total power demand [0], and that is just residential.

Perhaps we cannot replace all power using brownfield PV but we shouldn't just disregard the desert or other pristine ecosystems without also utilizing other alternatives to minimize our impact.

[0] https://www.google.com/amp/s/www.computerworld.com/article/3...


> So essentially you are saying we should destroy the environment because it appears to be cheaper in the short term?

"Destroy the environment" is not a binary variable. Decentralized installations could also result in more emissions from transportation to reach all the places, it could eat up more resources (steel) for the support structures. No action you take (or don't take) will have zero side-effects.

So, I'm saying pick the most lifeless places you can find that are still reasonably close to some power distribution infrastructure and put it there. But of course also put it on rooftops and industrial ruins where reasonable. It's not an either/or thing.

> but we shouldn't just disregard the desert or other pristine ecosystems without also utilizing other alternatives to minimize our impact.

It's not disregarding them, it's making tradeoffs. If we need some cheap, flat, unobstructed land to get PV deployed then some marginal desert can be a better choice than cutting down forests, draining swamps or covering arable land.


I agree that protecting desert ecosystems is important, but isn't desertification more of a problem than "rapidly disappearing" desert?


desertification is the destruction of arable land, not the expansion of healthy desert ecosystems. Healthy desert ecosystems are disappearing, not expanding


Deserts are rapidly disappearing?


Pristine deserts are. Invasive species, drought, and human development are all damaging desert ecosystems, which take much longer to recover than less arid biomes.

Just because deserts appear barren doesn't mean there isn't an ecosystem there that isn't important.


Makes sense.


It plain makes more sense to generate the power as close to use as possible


It doesn’t make that much sense. We can transmit power pretty long distances these days.

I don’t understand “don’t disturb the desert” - why? It’s not just useless to us… it’s useless to most living things.


I don't know where OP got that from, but we don't actually need to use it, an a lot of things live there. It isn't all just bare sun bleached rock and sand. https://www.desertmuseum.org/desert/sonora.php


"things live there" can also be true about gamma-ray sterilized canned food[0]. That doesn't mean it's important to the continued functioning of the ecosphere. Also, some deserts are more lifeless than others.

[0] https://en.wikipedia.org/wiki/Deinococcus_radiodurans


I don't see what point you are making that contradict my original comment. Yes deserts are less important to the health of the planet than biodiversity hotspots, but why would we destroy them when we have other alternatives?


Hasn't area of desert increased a lot in recent years. We hear, for example, about increased desertification in Saharan Africa. If we reverse some of that desertification that would seem to help?


From my other comment:

desertification is the destruction of arable land, not the expansion of healthy desert ecosystems. Healthy desert ecosystems are disappearing, not expanding


Then they're orthogonal, and siting such projects on land that has become desert in the last century, say, will not harm these "healthy desert ecosystems" you speak of?


> We can transmit power pretty long distances these days.

Engineering feasibility is not the same as economic viability.


Or political


There will always be trade off no matter where we decide to put them. Either that or we return to living in villages and forget about modern civilization.


Not really sure how you went from not destroying the desert for PV to living in villages and forgetting modern civilization, seems like a big jump. There are other alternatives which I mentioned that we can utilize before we need to make the trade off that you're talking about.


I'm guessing that all these schemes timeshare one resource - people - who then diversify their enterprises by wearing two hats.

Sort of how a convenience store has a storefront, then keeps leveraging it by adding things like moneygrams and lottery ticket sales and utility bill payments and so on...

I also think there must be crops that benefit from shading. Either the crops grow well in indirect sunlight, or the area is too hot/sunny for the direct sunlight crops.


the plants help keep the solar panels cool which aids efficiency and longevity


They don't seem they elaborate to me, at least compared to any other engineering project that engages the real world. I'm just wondering what took them so long.


Just plant that type of grass the herbivores really like and let the cows, sheep and goats roam. We can't only eat plants we need cheese too.


This is the only solution that makes sense everywhere where land is not a million dollars an acre (places not California).


Arable land in England is about $10k an acre. Until the council grants permission to build housing on it, then it jumps to between $500k and $2m an acre because housing is in such short supply.


This is partly because the UK is addicted to cheap food and has no interest in food security. The big supermarkets can push the price they pay for produce so low that farmers can't make a living so there is little demand for farmland.


Yeah, but that one solar farm that tried to game farming subsidies by letting goats roam with no change to the panels or racking had 3 panels damaged so that's impossible /s


Just gotta keep the goats off the panels (a real problem!)


Actually, we don't need cheese.

It's more that we want cheese


Yes this, and car parking lots


And over the top of every aqueduct, storm channel, and man made 'river' designed to deliver water to large urban areas. Generates power and helps reduce that annoying evaporation.


It would be cool to see photovoltaic's manufactured into shade spheres like these things:

https://youtu.be/mEmwJzQjwyw

Maybe they could combat algae blooms at the same time too


This is a very CA-centric research topic. In most of the US heartland theres millions and millions and millions of acres of farmland. There’s no need and limited benefit to mixing PV with agriculture.

And the places where it does make sense it makes sense only for running goats around in the PV sites to keep weeds down.


Farming and hot sunlight isn’t something that only exists in california.

High population density countries also do farming and using every inch of land is essential. Demand for things sensitive to harsh sunlight (herbs, berries, and so on) or in places with long dry seasons means growing under shaded areas has advantages, and doubly so if you can extract energy while doing so. That’s also not exclusive to california.


That's a very USA-centric comment. To the best of my knowledge, the two countries doing most research on agrivoltaics are Japan and China.


The countries that develop, build, and sell solar panels? Not surprising.


Sure. But also, consider the availability of arable land relative to population.

I would argue countries like USA, Canada, Brazil, Australia are the outliers. Most of the world cannot afford to be as dismissive of land use optimisation as some US Midwestern farmers appear to be.


There are solar farms being installed on previously very productive farm land near me. Between the thousands of truckloads of gravel and the steel piles being driven into the ground as far as the eye can see, I doubt the land will productively grow food of any kind for a century or more.

edit: I apologize if this is difficult to hear.


We've plenty of productive farmland.

We don't yet have enough renewable energy.


It costs you, personally, nothing at all to hold that opinion.


We dedicate 39 million acres to corn ethanol so our gas is 10% ethanol. 15 million acres of panels would supply all of the US energy needs including all current petroleum energy.

1 acre of corn produces 11 million kcal. 1 acre of solar panels produces 300 million kcal.


I’ve long wondered why solar panels and wind turbines aren’t colocated, as the power transmission infrastructure can be shared.

In Germany, power companies are installing turbines in farmers’s fields. Solar is harder (but you could mount it higher — harder to wash though).

I’ve seen solar installations in India overgrown with vegetation.


> I’ve seen solar installations in India overgrown with vegetation.

I wonder what the institutional setup behind that is. Whoever gets power from the solar installation has a clear incentive to keep them from being overgrown, so I assume there must be some horrible corrupt principle-agent conflict style stuff going on in the background. (Very typical of India, alas.)


I have always assumed that the situation is that someone (NGO a or government) pays for the installation but nobody pays for or trains on maintenance.


Yes. If you had a clear owner, they presumably would have an incentive to pay for the maintenance, or sell to someone who can pay for the maintenance.


In many countries it's hostile legislation to make it worse and increase soft costs. Australia was only recently allowed to include batteries on solar.


> Australia was only recently allowed to include batteries on solar.

Source? Tesla Powerwall was introduced into the Australian market in 2015. From what I understand, other residential systems existed before that, but they were uncommon. In 2019, they significantly tightened the safety standards, but the impact on people running approved off-the-shelf systems (such as Tesla's) is modest (tighter rules on installation locations may cause issues for some people, especially smaller properties–although those rules only apply to new installs, existing installs are grandfathered), most of the added burden is on those rare people who have bespoke systems.


Utility, not residential.


When you are this brief, I’m left guessing as to exactly what you are saying.


I'm with @ skissane on asking for a source here.

FWiW myself and friends put a solar power system with recon'd Telstra batteries together for an off the grid house out the back of Bridgetown (W.Australia) in the mid 1980s.

Given it was private land and farming jack of all trades engineering maybe it was "illegal" - but I recall no mention of that at the time in any of the magazines we read and ears we pulled.


I find it hard to believe it was against the law to use batteries to store excess solar power.


I'm guessing the comment was about regulating against sufficient large battery installations in a dense urban setting until standards where in place.

Australia has a high (very high by world standards) % of houses with solar panels on the roof which feed power back to the main grid (in cities and surrounding towns) which minimises the need for battery walls (which will no doubt come soon enough).

In (sub)urban housing in Australia it's against zoning for residential houses to have large tire piles (ie an entire yard of old car tyres with more house high stacks out the back) due to the dangers of dirty fires, ditto having a shipping container of fireworks next your house (and other houses in area), massive fuel tanks, etc.

I dare say large battery walls were also zoned against until plans were in place re: standards, etc.

Australia does have neighbourhoos battery banks here and there, one that serves 200 houses (at mean consumption) can be purchased for ~ $1 million AU (IIRC) - and there's the South Australian battery bank that was the world's largest when it was installed.


> In (sub)urban housing in Australia it's against zoning for residential houses to have large tire piles (ie an entire yard of old car tyres with more house high stacks out the back) due to the dangers of dirty fires, ditto having a shipping container of fireworks next your house (and other houses in area), massive fuel tanks, etc.

From what I understand, planning regulations (Australia's "zoning laws") don't always specifically prohibit those things. Rather, it is illegal to have something dangerous on a property, especially a residential one – but rather than list every possible thing that could be dangerous, it is more that local government has the power to decide on a case-by-case basis, and you can challenge their decision in the courts if you disagree with it. Some of those things – such as explosives (fireworks) – are also primarily regulated by state agencies, rather than local governments (who have the primary responsibility for zoning). Unlike the US (for instance), we don't have local fire departments, the fire department (or "fire brigade" or "fire service" or "fire authority", which are more common terms in Australian English) is generally a state government agency, and it shares responsibility with local governments for fire safety. Zoning intersects with some aspects of fire safety – building setbacks are often partially motivated by fire safety concerns, but also by other concerns such as visual amenity – other aspects of fire safety regulation are really orthogonal to zoning.

> I dare say large battery walls were also zoned against until plans were in place re: standards, etc.

I don't think there was ever a rule per se against battery systems in residential areas (and especially not a "zoning" rule). There are a set of known risks that they pose – fire, arc flash, electric shock, chemical burns, etc – and you need to prove you are adequately managing those risks. Before commercial off-the-shelf systems were widely available, you'd have some bespoke system requiring review on a case-by-case basis – obviously that's a lot more time-consuming, expensive and uncertain in outcome. With a commercial off-the-shelf system, the manufacturer will get it approved as a type, and then it just becomes the much easier question if this particular install is following the rules for that type approval.


Fair enough, Australian urban development requires approval - and things previously approved are typically a shoe-in, the new and novel requires a bit of thought and can face delays and|or outright rejection for some time.

I've had a house or two in Perth over the years but I mainly live and work in rural or undeveloped outback locations and rarely face any pushback over experimental builds and installations.


Outside of weird edge cases (like mushrooms), how does this work when the plants use the sunlight and so do the solar panels?


There are plenty of places in the garden around my home that either are always shaded or are only in full sun for a few hours a day. Yet there isn't one spot (except under my house) where nothing grows. Suitable spacing, height and angle of panels (which could adjust during the day) and choice of crop all would come into the mix of what would work.


for staff-of-life crops like potatoes and grains, it's a bad idea, but an awful lot of common crops like lettuce benefit from having less than full sun



People pay rent for land use. Solar panel income on marginally productive land which actually increased yield of different crops with reduced sunburn, bolting and watering costs combined with revenue in rent, might be better economics than high yield, high water, high till, high fertiliser crops.


Transparent solar cells. https://www.nature.com/articles/s41598-022-15352-x I think this is far more interesting than Fast Company speculation.


The website blocked my IP from reading the article because it found my uMatrix suspicious. Just tell me to disable it or deny access to the site. No need to lock out people who like to decide where their computer connects to. That is a bit petty.


This could work well for small scale farm lands owned by small families as these farm lands use more manual labors than tractors. The farm lands I am talking about are like the ones in the highlands in South East Asia.


They’re talking about transparent solar panels right? HN has been very weird lately. Was this article topic suggested by chatGPT?


No, it's for the areas with excessive insolation - the idea is to use solar panels to create some shadow, reducing the exposure to sunlight for crops and wildlife, which benefits both.


Which means bifacial panels would suit even better


Bifacial panels are the default now. They're just better.


Elon Musk once said:

"So, there's quite a big keep-out zone, and when you factor the keep-out zone into account, the solar panels put on that area would typically generate more power than that nuclear power plant."

I always wondered if that is really true?


This idea is being pushed hard right now. I see it everywhere.

You can't grow most crops under solar panels. And the crops you can grow will probably have a lower yield.

This is an idea that's meant to push replacing farmland with solar arrays. I don't necessarily think that's a bad idea for low yield soils, but in my area they are trying to replace high-yield soils (former orchards, vineyards, market gardens) with solar arrays. It doesn't make sense.

What would make sense is arrays that are semi-portable that can be used for re-establishing topsoil. With the right crops, good topsoil can be reestablished in as little as 5-10 years.


I just added this comment below: https://news.ycombinator.com/item?id=35101717

A lot of farming NEEDs sun protection for better yields. Currently farms that don’t have sun protection over compensate by over watering (also could reduce yields).

Not to say every farm should have solar panels but it’s very likely a double digit percentage of farm land would benefit from agrovoltaics.


I'd imagine a significant majority of mass-produced lettuce is grown with some sort of shading to prevent bolting.


Let me introduce you to El Ejido, Spain. A region dominated almost exclusively with greenhouses that block out significant amounts of sunlight

https://en.wikipedia.org/wiki/El_Ejido

https://www.google.com/maps/@36.7520281,-2.7656489,22159m/da...


True, however I think the point is to put more shade tolerant crops under the panels. A lot of the crops we grow are not grown directly for human consumption.

Consider the corn grown for the production of ethanol: why not just harvest the energy directly with solar panels there and grow lettuce or carrots? It would be good to explore other uses for the space as well, like using the panels as shade or cover for livestock.


I mostly agree. As an aside, growing maize for ethanol in the US is only really viable because of subsidies and tariffs. Otherwise, Brazilian ethanol would be cheaper.


Ethanol in the USA is a scam that representatives from states that benefit from the subsidies keep alive.


There are plenty of crops that grow well in or even prefer partially shaded conditions, particularly if there's a significant amount of reflected light as well as there likely would be around a solar array.


> You can't grow most crops under solar panels

What sort of crops and how long are the panels blocking sunlight for?

For some crops there is such a thing as too much sunlight (or too much heat).


I think the idea is to use this on the handful of crops that prefer the shade. Think small artisanal alfalfa farms with minimal mechanization.

But all in all I agree that it adds considerable complication for little gain. At least in the US we are in zero danger of installing so many solar panels that there is not enough acres left for food. That kind of concern is orders of magnitude away from reality. Especially if you start displacing corn-for-ethanol acres with solar panels used to charge electric vehicles. In that case you actually increase the available acreage for food crops because the solar panels are so much more efficient than corn ethanol.


Not just alfalfa, but crops where what's eaten is the stems, leaves and other parts of the plant more than the fruits/seeds. Leafy greens, some root vegetables both starchy and wet, asparagus, some brassicas, etc. Not nearly as broad a list as full sun, but I'm also sure there are a lot of things being grown in southern California now that needed a lot of breeding to deal with as much sun as they get there.


Exactly. This idea is so dumb, it reminds me of solar powered roads or solar power on the roof of your car.

There’s no shortage of land out there that can’t be used for agriculture. The American southwest is full of empty land that just happens to be very sunny. There’s no need to comprise the productivity of farms and solar farms alike to try and squeeze them into the same space. Wind turbines on the other hand can work beats they don’t get in the way as much, especially on grazing land.


> There’s no shortage of land out there that can’t be used for agriculture. The American southwest...

Maybe not in the US, but in more populated parts of the world there very much is a shortage of land of any kind.


The article says that having crops under panels might help them through cooling. Options are worth investigating if it makes the whole system more viable.




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