Growing crops under solar panels
fastcompany.com
fastcompany.com
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/...
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.
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.
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.
> 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?
> 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.
Hyperbole much? The polar night is a lot further north.
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.
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
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”.
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.
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.
What’s in OPs image is a greenhouse. The sides can be closed if low temperatures are coming in at night.
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 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.
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.
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 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.
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.
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.
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.
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.
And also, the degradation that you see on sun-damaged clothing is mostly on the dye, not the underlying fabric itself.
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.
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.
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
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."
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.
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.
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.
I don’t understand “don’t disturb the desert” - why? It’s not just useless to us… it’s useless to most living things.
Engineering feasibility is not the same as economic viability.
desertification is the destruction of arable land, not the expansion of healthy desert ecosystems. Healthy desert ecosystems are disappearing, not expanding
Just because deserts appear barren doesn't mean there isn't an ecosystem there that isn't important.
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.
Yes, like the places I mentioned in my comment
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.
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...
"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.
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.
Maybe they could combat algae blooms at the same time too
It's more that we want cheese
And the places where it does make sense it makes sense only for running goats around in the PV sites to keep weeds down.
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.
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.
edit: I apologize if this is difficult to hear.
We don't yet have enough renewable energy.
1 acre of corn produces 11 million kcal. 1 acre of solar panels produces 300 million kcal.
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 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.)
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.
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.
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.
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.
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.
"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?
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.
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.
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.
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.
Maybe not in the US, but in more populated parts of the world there very much is a shortage of land of any kind.
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.
https://en.wikipedia.org/wiki/El_Ejido
https://www.google.com/maps/@36.7520281,-2.7656489,22159m/da...
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).