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Vertical farming does not save space

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Re: Vertical farming does not save space

#341

Post by Retric »

sir_bearington wrote: post #236
Retric wrote: post #225

Earlier quoted context omitted.

Try running the numbers for actual lifespan. Callaway is 1,190 MW on 2,767 acres at 87.70% over it’s useful lifespan, but that’s ignoring permits + construction = 10 years and decommissioning which takes ~30 year. Even a generous 55 year operating lifespan is still reduced to 87.7 * (60 / (60 * 10 + 30)) = 48% capacity factor. Using a 20% capacity factor for solar (aka non tracking in a good but not great area). That…

30 year decommissioning is a very pessimistic assumption. Also most new nuclear plants have operating lifetimes closer to 80 years than 55. You also have to adjust for the overproduction necessary to make intermittent sources a reliable primary provider of electricity. In far north or southern latitudes, angle of inclination is such that solar panels collect ~70-50% less energy than near the equator. This gets worse…

30 year decommissioning is somewhat optimistic average based on current plans.

https://en.wikipedia.org/wiki/SAFSTOR “For nuclear power plants governed by the United States Nuclear Regulatory Commission, SAFSTOR (SAFe STORage) is one of the options for nuclear decommissioning of a shut down plant. During SAFSTOR the de-fuelled plant is monitored for up to sixty years before complete decontamination and dismantling of the site, to a condition where nuclear licensing is no longer required. During the storage interval, some of the radioactive contaminants of the reactor and power plant will decay, which will reduce the quantity of radioactive material to be removed during the final decontamination phase.”

For example, Crystal River 3 (Florida) “Duke Energy announced in Feb-2013 that the Crystal River NPP would be permanently shut down.” “Systems Removal & Building Remediation(2070–2072)“ and that’s if things go well. https://en.wikipedia.org/wiki/Nuclear_decommissioning

As to indoor farming.

“It’s not just that the 4 billion tons of uranium in seawater now would fuel a thousand 1,000-MW nuclear power plants for a 100,000.”

That sounds like a lot, but of you want ~100w of power per m2 that’s 0.1GW of power per km2. So your 1,000 GW power plants are only replacing 10,000km2 of farm land. Meanwhile agriculture takes 51,000,000km2 worth of land. In other words replace 20% of global farmland and you got ~100 years worth of uranium from all the worlds oceans, it’s replaced by rocks.

But, “And those rocks contain 100 trillion tons of uranium.” gives you 2,500 years which is not bad, but that’s not going to be replaced.

PS: You might be able to beat 100w/m2 indoors, but remember this is also for 20% of farmland.

Re: Vertical farming does not save space

#342

Post by trickstra »

TheCoelacanth wrote: post #322
jobe_br wrote: post #279

Earlier quoted context omitted.

Nevermind that land used for energy often isn’t suitable for farming, so … even with the hypothesis, limited as it is, it’s flawed.

Less suitable than empty air 10 feet above the ground? How is vertical farming powered by solar panels better than building the same artificial growing environment at ground-level and powering it with sunlight?

Because you can put the solar panels above a parking lot. You can't directly compare land area for growing with land area for solar panels, qualitatively, they are two very different lands. We have more of the latter.

Re: Vertical farming does not save space

#343

Post by trickstra »

Ekaros wrote: post #85
bee_rider wrote: post #68

Earlier quoted context omitted.

The cost of transporting the conventionally grown plants would have to be accounted for as well, but I'd be pretty surprised if that got anywhere near tipping the scale over to vertical farming.

I wonder if that could be solved more easily. Build sufficient rail network and hydrogen/electric/other zero-carbon trucks to move produce from production to there and then train it in. And this is really a sector we could fully automated almost already.

Switch hydrogen for methane and produce that methane in a bioreactor from the food scraps. These technologies are already here, no need to wait for a future hydrogen car.

Re: Vertical farming does not save space

#344

Post by matkoniecz »

perl4ever wrote: post #316
skissane wrote: post #126

Earlier quoted context omitted.

> If we look into the relatively near future, fusion energy is going to account for a rapidly increasing share of energy production by the end of this decade. I really don't think by the end of this decade there will be any commercial fusion production. I'm sure we will be closer but it is still some decades away. ITER proposes to follow up their current research reactor with a successor (DEMO) which they plan to sta…

When I read that timeline, it doesn't sound serious to me. If you're planning to do something in 40 years, then you don't have the faintest clue how to do it now, which means you don't know when you will know how to do it. It could be 5 years or 1,000 or never. You don't know what you don't know.

"First commercial fusion power station will start construction between 2050 and 2060" is mostly guess, but it is an educated guess based on some trends/predictions/achieved work.

But compare it to "First commercial perpetum mobile power station will start construction between 2050 and 2060" or "First FTL spaceship will be launched in 2050s".

Re: Vertical farming does not save space

#345

Post by sir_bearington »

strken wrote: post #317
sir_bearington wrote: post #263

Earlier quoted context omitted.

No, it's not "worst case we spent a bit more". Total global lithium ion battery production amounts to less than one hour of storage for the United States alone . Things like pulleys and synthetic methane remain in the prototyping stage. By this logic why not just use fusion? It's possible. We don't know which exact approach we'll use (lasers, magnets, etc.). We don't know how cheap it'll be, but hey it'll happen even…

You or I could go out today and buy off the counter parts, build a scale model of a pulley system, and use it to store power. We could have done that a century ago. To the best of my knowledge, fusion only demonstrated net-positive energy production this decade, and hasn't yet reached ignition in a man-made device. They're not the same.

Yeah you and I could built a simple pulley system and store gravitational potential energy. Physics works, I know I'm not surprised. But we couldn't use it to store moderately enough energy to be useable to decarbonize our energy footprint. And building them at scale is a gamble on unprecedented application of technology.

It's like trying to be carbon neutral through burning biomass. Yeah, it works as a general principle. But the energy density just isn't there. The US consumes about much energy each year as we'd get from clear-cutting the entire country over the span of a single year. And the plants take longer than that to grow. Sure, we could try more exotic things like dumping iron into the ocean and harvesting algae blooms. But as a general principle, biomass energy source doesn't scale well.

Same with energy storage. Nuclear isotopes are a great store of energy. The best we know how to tap into in term of energy density, that's why we use it on submarines. Chemical energy like methane is good, but the sabatier process isn't that feasible and it needs a pre-existing source of carbon dioxide. Electrochemical storage like batteries is great for systems that need to store a relatively small amount of energy, like cars and electronics. But it isn't available at nearly the required scale. Hydroelectricity storage is better for scale, but still not good enough. And I'm sure you can name other proposed systems like pulleys, hydrogen, compressed air, an d more. But the point is that until they've demonstrated commercial viability let alone beaten competitive solutions it's a big assumption to factor these into solutions to climate change.

Are people accepting contracts to store X GWh of electricity in pulleys, or or compressed air and operating those projects successfully? Until then, these do not represent presently available solutions to climate change. I'd be happy to be proven wrong, but until then saying we have a realistic plan to provision enough energy storage to decarbonize through renewables is counterfactual - at least save for places like Norway or Iceland that have dispatchable sources of renewable energy nearby in the form of geographically dependent hydro and geothermal power.

Re: Vertical farming does not save space

#346

Post by bpodgursky »

wainstead wrote: post #306
modriano wrote: post #301

Judging vertical farming based on the performance of wheat is not valid. When I saw the test crop was wheat, I scrolled to see if there were any other crops, saw that there weren't, and abandoned the article because wheat has among the worst yields per area (in terms of kg of edible product per sq meters). Since the pandemic started, I started experimenting with hydroponics and I've been growing basil, kale, mint, ch…

> Judging vertical farming based on the performance of wheat is not valid. When I saw the test crop was wheat, I scrolled to see if there were any other crops, saw that there weren't, and abandoned the article because wheat has among the worst yields per area (in terms of kg of edible product per sq meters). I want to stress this point. Crops like wheat, rice, and corn are not suitable for vertical farming. No vertic…

> Water from precipitation is a fraction of the water needed in areas like the American central plains where the Ogallala Aquifer has been pumped out for decades

This isn't true. Much (at least a couple of years ago, most) corn in the midwest is not irrigated. Rainfall is common enough over the summer that it almost always works out OK, and if it doesn't, you write it off to crop insurance.

Edit: double checked, still confident. Check out the page 4 map of the midwest and % of irrigated corn fields https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=2...

Re: Vertical farming does not save space

#347

Post by jbm »

modriano wrote: post #301

Judging vertical farming based on the performance of wheat is not valid. When I saw the test crop was wheat, I scrolled to see if there were any other crops, saw that there weren't, and abandoned the article because wheat has among the worst yields per area (in terms of kg of edible product per sq meters). Since the pandemic started, I started experimenting with hydroponics and I've been growing basil, kale, mint, ch…

Hey, I was hoping you could share some resources about this subject! I always have a hard time finding any useful information about hydroponics and would love to learn more.

Re: Vertical farming does not save space

#348

Post by pilord8 »

This article makes a mistake by assuming that an installation (TheFarm) represents the best we can do with vertical or indoor farming. Of course an exploratory art installation isn't going to be particularly cost conscious - it's not designed for that, not really.

Instead, the obvious counterpoint is to look at currently vertical farming installations. The one I'm most aware of is Plenty, which has 350x the yield of standard outdoor farming. At that level, it's leafy green products are organic and cost competitive (i.e., the same price) as other organic spinach/kale/arugula brands.

This is really substantially understating the case for Plenty, but I don't think I can say much more and I would encourage anyone interested to just go look up what they and other vertical farming operations are doing.

Re: Vertical farming does not save space

#349

Post by godelski »

tux1968 wrote: post #74
maxharris wrote: post #59

Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. The vertical farm is a paradox unless fossil fuels provide the energy. In that case, there’s not much sustainable about it. This entire piece is based on the assumption that the only sources of…

The other thing to remember is that there is a lot of land that isn't suitable for farming for one reason or another that can be used for solar.

This is a surprising concept missed by many, especially in energy. Since places solar is the best. Some wind. Some hydro. Some nuclear. The world isn't homogeneous. I see the same thing with farming. Indoor and vertical farming allows you to farm in the middle of the dessert. In Africa where hippos eat your crops. Closer to population centers where you reduce emissions from transportation and increase food security (longer roads mean more chance of food trucks getting stopped, due to accidents, climate, whatever). You can't compare these things on singular metrics. You have to look at the whole picture. In some instances things will be better, other instances worse. You have to balance complex equations.

Re: Vertical farming does not save space

#350

Post by officehero »

matkoniecz wrote: post #344
perl4ever wrote: post #316

Earlier quoted context omitted.

When I read that timeline, it doesn't sound serious to me. If you're planning to do something in 40 years, then you don't have the faintest clue how to do it now, which means you don't know when you will know how to do it. It could be 5 years or 1,000 or never. You don't know what you don't know.

"First commercial fusion power station will start construction between 2050 and 2060" is mostly guess, but it is an educated guess based on some trends/predictions/achieved work. But compare it to "First commercial perpetum mobile power station will start construction between 2050 and 2060" or "First FTL spaceship will be launched in 2050s".

The educated guess for the last 50 years was 20-30 years away
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