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Vertical farming does not save space

lowtechmagazine.com

251–260 of 464 posts

Re: Vertical farming does not save space

#251

Earlier quoted context omitted.

Nuclear's cost is almost entirely in the infrastructure, and it's paid over a very long time period. The business plan for nuclear is to spend a decade or two paying back your loans, after which you make big $$$ because the plant costs relatively little to run. The ideal plan for nuclear is to pump out power at 100% 24/7. You save nothing by being idle, and you want to pay off your loan as soon as possible. All that…

Yes, nuclear hardly costs any more to run at 100% capacity than it does at 50% capacity. That's why decarbonization with renewables as a primary source doesn't make much sense. Solar and wind are both intermittent. Wind is dependent on the weather and experiences situations with near zero production for long stretches of time. Solar is also weather dependent, and has day-night cycles on top of it. This is fine if you…

The issue as I see it is that pretty much nobody is looking at decarbonizing a grid, money be damned.

Unless your power production is run by the government, generation is done by companies looking to make a profit. Solar and wind companies don't mind in the slightest that they're screwing up the business model of nuclear. The fact that their production is intermittent isn't important to them -- it's already accounted into their business model, and nuclear's lack of ability to deal with that and grid stability is somebody else's problem.

If you think nuclear is the solution here you must be prepared to pour many billions of tax money on supporting its existence even though it's currently unprofitable. China can do that, because China's government has the long term control and lack of concern about public opinion to get such things done.

Politicians in democratic nations in general lack such a luxury. They know that they can get kicked out of power before their first plants get built, and then the successor either pulls the plug on the project entirely, or keeps whatever got built, but almost definitely nowhere near close to the full capacity needed.

You'd have a hard time skipping the renewables, because you'd essentially have to forbid them. You'd have to go there and make a law that you can't build solar even though it would produce power that's twice as cheap, or take craploads of tax money and subsidize nuclear. I suspect neither is going to look very good in the news.

Re: Vertical farming does not save space

#252

Vertical farming will almost certainly not generate the mass of calories to feed the world. But that doesn't mean it cannot be useful. Many vegetables are already grown under very controlled conditions and it doesn't take much fantasy to consider, e.g., tomatoes from a nearby vertical farm more environmentally friendly than their counterparts grown in some remote sunny place. But of course, logistics might get cheape…

Why can't large grocery stores be built taller to grow vegetables horiz/vertical airoponically on an upper level? No need to raise disgusting "pretty" vegetables that are picked green, artificially-ripened, and driven thousands of miles.

Re: Vertical farming does not save space

#253
i think one thing the author is missing is that power is much easier and cheaper to transport than either food or water. the best places to grow food are not always near people and a lot of unused land has reasons for its state. installing solar power to create production in the desert is vastly cheaper then pumping water there, and then transporting the food back to populated areas.

i can think of about 50 other inputs the author failed to include, i don't think it's as simple as comparing square footage efficiency.

Re: Vertical farming does not save space

#254
post #82
post #74

Earlier quoted context omitted.

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.

It's such an important point that's the core value proposition of vertical farming. Arable.land is unlikely to keep up with the combination of population growth and climate change. That's the whole point of the exercise! Solving that problem!

World popolation is around 7.8 billion, and is projected to peak around 11 billion. Given that of all agricultural land only 23% is used for non-feed crops (producing 82% of global calorie supply) that doesn't sound like an existential problem, even if you assume that climate change makes much more land unarable than it makes arable.

Re: Vertical farming does not save space

#255

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…

> 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…

One problem with ITER is that it’s only point is to demonstrate ignition. It’s completely unfeasible as an actual power plant. I’m not saying it’s not useful, but rather it has a close to 0% chance of producing a scalable power plant, whereas some of the other smaller scale operations are less likely to reach ignition, but if they do so more likely to result in a viable design at scale.

Re: Vertical farming does not save space

#256
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.

What signs do you see that it might work at all (and that it's not a hopeless endeavor)? As a layman it's so hard to understand how something so hot and so confined could ever be made to react reliably with continuous fuel and energy production to produce power on a large scale.

I don't think anyone is proposing continuous fuel (even fission reactors typically don't work like that - you have to shut them down to swap out the fuel rods periodically). The idea is that you inject (say) some deuterium into a blast chamber, it explodes like a miniature thermonuclear bomb, and you gather the explosive energy in vaguely the same way a internal combustion engine (like in cars) gathers energy from fuel-air bombs in its engine cyliders.

And we already know (roughly) how to build that, it's just that the version we know how to build is so ridiculously, impractically huge that you could fit a small city in its blast chamber... because it runs on actual, non-miniature, thermonuclear bombs. The difficulty is scaling that down to something that doesn't have a upfront cost measured in multiples of the world GDP before it starts generating power (in quantities measured in multiples of current global electrical consumption, and likely multiples of global energy consumption period).

Re: Vertical farming does not save space

#257

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…

A lot people miss this point, so thank you for bringing it up. It drives me nuts that it's so prevalent out there!

Re: Vertical farming does not save space

#258

Earlier quoted context omitted.

Yes, please include the cost of nuclear power in the considerations. (The joke here is that the true cost is undefined because we here in the US have no method to store the long-term hazardous waste it produces. Current cleanup costs for just the military reactor waste are estimated at $500B, for civilian reactors the costs are said to be higher.)

the US has 80000 tonnes of spent nuclear reactor waste. SpaceX launch cost in 2017 was $2700/kg. presumably lower now. by my math, that's $215bn to launch all our nuclear waste into space. Is there a reason that's not a viable option?

I still think that declaring that waste is a waste.

That is potential future fuel.

Re: Vertical farming does not save space

#259

Earlier quoted context omitted.

> Right, as evidenced by the extensive storage infrastructure being deployed /s. Invalid argument. > The US has 25 GWh of storage, as compared to an hourly electricity consumption of 500 GWh. Literally less than ten minutes of storage. Almost all of it hydroelectric, which is a big infrastructure project on par with building nuclear power plants Irrelevant point. Storage was marginal in the past because there wasn't…

California has already saturated the daytime energy demand on sunny days. So does Hawaii. The market forces already exist. But people aren't building storage. Because it's not feasible, short of a decisive breakthrough in storage technology. Maybe one of the proposed storage solutions will pan out. But building out trillions of dollars of infrastructure projects on the hope that a future breakthrough will make storag…

> The market forces already exist.

And that is a recent thing there. The global market is still developing, and technologies don't materialize instantly. CO2 taxes are still low (or zero) just about everywhere.

But hey, I hope you are also not going to claim nuclear will be cheaper in the future, because I could reflect that argument right back at you. And I could observe that, unlike with renewables and storage, nuclear has a horribly bad historical experience curve.

> Maybe one of the proposed storage solutions will pan out. But building out trillions of dollars of infrastructure projects on the hope that a future breakthrough will make storage feasible is very risky.

It's only a $$$ risk. We absolutely know the storage is possible, we just haven't confirmed how cheap it will be. Worst case is we spend a bit more. This is fine. Investments are not guarantees; one is always gambling.

Re: Vertical farming does not save space

#260

Earlier quoted context omitted.

What signs do you see that it might work at all (and that it's not a hopeless endeavor)? As a layman it's so hard to understand how something so hot and so confined could ever be made to react reliably with continuous fuel and energy production to produce power on a large scale.

I don't think anyone is proposing continuous fuel (even fission reactors typically don't work like that - you have to shut them down to swap out the fuel rods periodically). The idea is that you inject (say) some deuterium into a blast chamber, it explodes like a miniature thermonuclear bomb, and you gather the explosive energy in vaguely the same way a internal combustion engine (like in cars) gathers energy from fu…

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