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Vertical farming does not save space

lowtechmagazine.com

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Re: Vertical farming does not save space

#211

Post by manfredo »

Retric wrote: post #167
mytailorisrich wrote: post #150

Earlier quoted context omitted.

That's the whole land belonging to the site, most of which is nature, not the plant itself, which looks like less than 200 acres, including the car parks. In any case, it's not close at all either for that specific example or in general, not least considering that a nuclear plant can produce 24/7 and that solar often does not reach peak production because of the weather. " A solar PV facility must have an installed c…

Look through several nuclear locations and ~1000 acres is fairly typical. In theory they could be more compact, but security concerns etc means nobody puts 2GW of nuclear on a 200 acre site. 1,000 acres, https://en.wikipedia.org/wiki/Beaver_Valley_Nuclear_Power_St... 1,782-acre, https://en.wikipedia.org/wiki/Byron_Nuclear_Generating_Stati... 2,767 acres https://en.wikipedia.org/wiki/Callaway_Nuclear_Generating_St...…

To put this in comparison, a solar farm would need 50,000 to 100,000 acres to match the net output of those nuclear plants. Plus the land used for energy storage, which would typically involve damming rivers which has its own set of ecological effects.

And it's possible to build much denser plants. The Shin-Kori facility in Korea is massive energy relative to the land it uses. Nuclear power is far more energy dense than solar or wind. This is just thermodynamic fact.

Re: Vertical farming does not save space

#212

Post by pfdietz »

benjaminjackman wrote: post #188
gh02t wrote: post #165

Earlier quoted context omitted.

I'm a nuclear engineer working at a laboratory known for fusion research. Commercial fusion power at any scale is not happening by 2030. 2040 or 2050 are more realistic and may still be a stretch.

That's interesting, do you think that SPARC and HTS advancements like for example VIPER cables point towards a faster path to market for fusion than ITER?

No, because the fusion reactors using HTS still have horribly lower power density. The ARC design has a power density 40x worse than a PWR primary reactor vessel, and involves far more difficult engineering. How is this going to be cheaper than fission, which itself is not competitive?

Re: Vertical farming does not save space

#213

Post by pfdietz »

cosmodisk wrote: post #186
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…

Don't know how old you are but it's very likely that your children or their children will get old before fusion energy becomes reality.

I don't think competitive fusion power will ever be a reality, unless one is talking about fusion in the core of the Sun.

Re: Vertical farming does not save space

#214

Post by pfdietz »

manfredo wrote: post #207
dale_glass wrote: post #144

Earlier quoted context omitted.

I don't see how nuclear can win over the long term. Solar and wind are simple and very amenable to mass production. Many parts of them are usable for other purposes -- we need generators for things other than windmills, inverters for things other than solar powerplants, etc. This means we're not making things as a one off, but doing mass manufacturing, and the different users all reap benefits. They're easy to produc…

Nuclear's non-intermittency is why it wind in the long run. Once intermittent sources fulfill demand during peak production hours, the actual cost of adding each usable watt goes up dramatically. If your goal is to run a primarily fossil fuel grid, supplemented by renewables that's fine. That's what Germany is doing. But if your goal is to actually eliminate carbon emissions, you need to factor in the cost of storage…

Storage solutions are advancing fast enough that your argument cannot succeed. What you are saying used to be sort of plausible, but the sell by date on it passed long ago.

Re: Vertical farming does not save space

#215

Post by pfdietz »

shuckles wrote: post #193
dale_glass wrote: post #171

Earlier quoted context omitted.

Why bother? What reason is there to believe a generator with blades attached to it is going to lose to a generator with a containment building and reactor attached to it?

Isn’t the issue that the windmill also needs a large battery to meet demand?

Storage is needed, but storage has finite cost, and the cost is falling rapidly. Nuclear's window of opportunity is now closed.

Re: Vertical farming does not save space

#216

Post by rini17 »

ampdepolymerase wrote: post #38
kibwen wrote: post #7

> 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. This doesn't have to be the case. Plants don't use all the sunlight that hits them, because available light isn't generally the bottleneck in plant growth. Note how most plants are green, whic…

Depending on the geography and building design, you can carry light to the plants via optic fiber. They act as a light pipe/optical waveguide. No need for any photovoltaic solar panels. However this design necessitates a skyscraper in the middle of the desert with nothing else blocking line of sight. Great if you are in the Middle East. Not so great for New York or Seattle. For the latter cities, a permanent barge on…

Are there any systems that can actually capture close to 100% of sunlight falling on the roof and carry it somewhere else? All the systems you link are only for replacing illumination for humans. They don't provide anywhere near light flux sufficient for plants.

Re: Vertical farming does not save space

#217

Post by _carbyau_ »

shuckles wrote: post #193
dale_glass wrote: post #171

Earlier quoted context omitted.

Why bother? What reason is there to believe a generator with blades attached to it is going to lose to a generator with a containment building and reactor attached to it?

Isn’t the issue that the windmill also needs a large battery to meet demand?

Yes-ish.

Although there are other options like pumped hydro (pump the water back up the hill) though clearly that has logistical limits.

Re: Vertical farming does not save space

#218

Post by pfdietz »

cbmuser wrote: post #66
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…

Yeah, don’t bother with reading articles that exclude the largest source of clean energy in US. Such articles have an ideological bias.

Yeah, ideologically biased like the President of Exelon (quoted from December 2018):

“The cost of new nuclear is prohibitive for us to be investing in,” says Crane. Exelon considered building two new reactors in Texas in 2005, he says, when gas prices were $8/MMBtu and were projected to rise to $13/MMBtu. At that price, the project would have been viable with a CO2 tax of $25 per ton. “We’re sitting here trading 2019 gas at $2.90 per MMBtu,” he says; for new nuclear power to be competitive at that price, a CO2 tax “would be $300–$400.” Exelon currently is placing its bets instead on advances in energy storage and carbon sequestration technologies.

Re: Vertical farming does not save space

#219

Post by dicroce »

e_y_ wrote: post #184
dragontamer wrote: post #113

Earlier quoted context omitted.

> lot of land that isn't suitable for farming We're talking about powering a hydroponic greenhouse. The alternative to "Solar Powered LEDs" isn't "plant things in the ground". Its "make a glass window on your roof". -------- "Plant things in the ground" is also cheaper, though it does suffer from potentially poor soil conditions. Still, it seems to me that spreading fertilizer across soil (and conditioning the soil i…

Or maybe something like what's being investigated for greenhouses on Mars (which gets less than half the sunlight that Earth receives) using mirrors and optical fiber cables to redirect light.

Yes! I wonder if there is a way to make a light battery? :)

Re: Vertical farming does not save space

#220

Post by pfdietz »

mannerheim wrote: post #86
hctaw wrote: post #61

Earlier quoted context omitted.

The greater problem to solve is maximizing nutrition for communities while minimizing the carbon costs of providing it. Vertical farms fit into that equation by moving production closer to the people that eat the produce, and making it more available to food/nutrition deserts in urban areas. Extending growing seasons or returning farmlands to wildlands miss that point. The bigger problem in the latter is livestock an…

Most of the carbon costs of providing food comes from the process of growing it, not transporting it. Most of the carbon costs in transportation also come from consumers driving to and from grocery stores. See: https://www.salon.com/2012/06/16/eating_local_hurts_the_plan...

In the US, we use more energy cooking food than we do growing it. Agriculture is only about 1% of total energy demand.
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