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Vertical farming does not save space

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Re: Vertical farming does not save space

#421

Post by Misdicorl »

macspoofing wrote: post #396
Misdicorl wrote: post #325

Earlier quoted context omitted.

A green roof is pretty. It has plenty of upside. It isnt a productive farm which is the appropriate comparison here

>It isnt a productive farm which is the appropriate comparison here Why would 'vertical farming' be more productive then?

Because productive farms require lots of expensive maintenance/equipment. A vertical farm lets you optimize for that use case since its the only use of the infrastructure and you can align everything towards maximum use of those scarce resources.

Random roofs don't optimize for that usage pattern, and so you need to use them in an application where the primary cost is the install cost rather than an upkeep cost. Solar panels are a perfect fit. Farms are a terrible fit.

Re: Vertical farming does not save space

#422

Post by AtlasBarfed »

The headline seems poor, the article not well structured.

Space isn't necessarily the major conservation of vertical farms. As stated in the article, water, soil, transport are all concerns in the total cost compensation, as are the current externalized costs in traditional agriculture loss of biodiversity destruction, soil erosion, and pesticide introduction.

Finally... they're growing crops totally indoors? Um... windows?

Solar panels can be placed on unused land (rooftops, deserts, etc), the false conclusion is that solar would be used on farmland or high biodiversity.

And there's wind.

What a train wreck. Almost a hit piece.

Re: Vertical farming does not save space

#423

Post by abandonliberty »

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.

Musk somehow got a bunch of those right. Not as complex, but still filled with unknowns.

Re: Vertical farming does not save space

#424

Post by perl4ever »

gh02t wrote: post #405
perl4ever wrote: post #320

Earlier quoted context omitted.

>barring investment on the scale of the Manhattan project The Manhattan project cost about $30 billion in today's dollars, I believe. We have IPOs that raise close to that amount of money these days (e.g. Alibaba). It's half a percent of federal spending in 2020 (admittedly not a normal year). GameStop has lost over $30 billion from its peak valuation. Your matter of fact claim that there's not enough capital in toda…

Comparing the raw numbers in terms of cost I don't think quite gives the right picture, you have to think about scale of investment. Whole (large) towns and biggest-in-the-world facilities were raised and the brightest minds committed. And it would likely take longer. Maybe a better comparison would be to the Manhattan project and the atomic weapons research apparatus in the decades that followed. Current input to fu…

>you have to think about scale of investment

That's what I was doing...

>currently fusion is not an appealing private investment outside of philanthropy. There are a lot of up front costs and uncertainty for a payoff that is way down the road

As opposed to the Mars rocket business? As opposed to money-losing biotech? Bitcoin, now representing around $1 trillion in total? Is the disinterest in long term investments why the US government is thinking about issuing 50 and 100 year bonds, as well as the 30 year that already exist?

In 2021, saying that significant capital is only available to non-speculative investments with short term payoffs sounds like something from another dimension. One without the GameStop hearings.

Elon Musk isn't literally the sole litmus test of whether fusion is feasible; he just represents the general zeitgeist. If a few billion dollars would make it happen in the near future, how could it be that everyone is disinterested? Especially now that taking climate change seriously seems to be snowballing.

Re: Vertical farming does not save space

#425

Post by perl4ever »

abandonliberty wrote: post #423
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.

Musk somehow got a bunch of those right. Not as complex, but still filled with unknowns.

My gut tells me that fusion power is better analogized to a space elevator than reusable rockets.

But you're suggesting what I already alluded to as a reason for doubting that economic fusion power will ever happen - he's the type of person who would be pursuing fusion if it seemed feasible. It's not that he's the only one, or that he knows about nuclear physics, but it's the sort of risk he would plausibly take if he didn't know of a good reason why it can't be done. Also, of course, you need power for Mars bases.

Re: Vertical farming does not save space

#426

Post by perl4ever »

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".

I would compare it to a space elevator (for earth, not the moon). Do you think we can attach a timeline to that?

Re: Vertical farming does not save space

#427

Post by dale_glass »

sir_bearington wrote: post #415
dale_glass wrote: post #382

Earlier quoted context omitted.

"Last time I checked France was a democratic nation. So was Belgium. Both of those have achieve majority nuclear power generation, and France over 70%." That was the past. The dynamics have changed, and renewables are much more competitive now. Nobody is building more nuclear right now. True, there's paranoia, but there's also economics. And I'm not talking about fossil fuels either. Here's what I expect to happen to…

> That was the past. The dynamics have changed, and renewables are much more competitive now. Nobody is building more nuclear right now. Uh... https://en.wikipedia.org/wiki/Nuclear_power#/media/File:Nucl... > Here's what I expect to happen today with a carbon tax: it'll kill fossil fuels, and give a huge boost to renewables. Nuclear won't benefit nearly as much, because renewables can sell each GW/h cheaper and are m…

That map isn't particularly meaningful. Sure, stuff is being built technically. But as far as I know, the main places where it's being done for real are China and India.

The UK for instance has one powerplant actually in construction and it already got a bad rap because it's a bad deal economically.

Besides that, I think you're missing my point. My point is that you have to deal with reality, and reality doesn't really align with the way you want things to work. For instance, you said:

"So why not just build the nuclear plants and skip the renewables?"

My question is: "Who 'we'"? In a lot of countries, there's no "we" that applies. There's a government that sets the rules, and private enterprise that builds the plants. If "we" is the government, then they don't build powerplants themselves. They may allow them to be built, but a company still has to want to.

And if "we" is the commmercial enterprise, then nuclear is far too big for anybody to build it out of sheer altruism or good PR. That's big money territory and it must make a profit.

If you simply impose a carbon tax, private enterprise will just go and build solar. We have no storage? Those companies won't care. It's not their problem to solve. They'll build whatever makes the most money, which is almost definitely not nuclear.

If you want nuclear to happen you'll have to force it somehow, and I'm not seeing any particularly attractive ways of doing so. You want to be the politician who runs on a campaign of forbidding or heavily taxing solar and wind at the same time as dumping billions of $ into nuclear construction? Yeah, that'll go great, I'm sure.

Re: Vertical farming does not save space

#428

Post by pfdietz »

Andrew_nenakhov wrote: post #406
pfdietz wrote: post #215

Earlier quoted context omitted.

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

Far from it. After years of promotion, investment and development, wind and solar energy prices dropped 10-20x in the last decades. Same cost reduction can very well happen with nuclear power, and it'll take far less space than solar and wind, will disrupt the nature less, and will be much more reliable and predictable, capable of producing energy on demand and not requiring any storage.

Nuclear had many decades in which its cost could drop. That failed to happen. Unlike with renewables, nuclear never had relentless cost decline. Its learning curve has even shown negative learning, with costs rising with time rather than falling. There's something about nuclear that just keeps it from getting cheaper. The scale and complexity of nuclear plants probably has something to do with it, and also the maturity of the non-nuclear side.

Re: Vertical farming does not save space

#429

Post by pfdietz »

sir_bearington wrote: post #277
pfdietz wrote: post #274

Earlier quoted context omitted.

No, it is "worst case we spend a bit more". We absolutely know that storage is possible. Pumped thermal electricity storage, for example, uses only well understood technologies. We solve climate change by raising CO2 costs high enough. Again, this is not a go-no go thing, it is just haggling over the price. > We're already at the point where markets are starting to see saturation with renewables. This just means CO2…

No, pumped storage is not feasible. It's both geographically limited, and it's not available at the appropriate scale. Estimates for how much storage would be necessary for renewables to work range from 12 hours to weeks of storage depending on the solar and wind mix. The US has ~25GWh of hydroelectric storage. There are no active hydroelectric storage projects at the moment, only proposals [1]. This is why proposals…

Pumped THERMAL storage. This is not pumped hydro. Rather, it involves a heat pump, for example compressing argon near-adiabatically, transferring the heat to a hot store (cooling the argon in the process), then expanding the argon back to the starting pressure. The argon is now around at mildly cryogenic temperature, and the cold is transferred to a cold store (liquid hexane, perhaps).

To recover energy, this is reversed, with the temperature difference driving the cycle in the other direction. Detailed calculations with inefficiencies show an overall round trip efficiency of 60% or better could be achieved. All the temperatures are below the creep limit of ordinary steel, so this system would require no exotic materials whatsoever.

It's also possible to design a thermal storage system without the cold store, using the ambient environment as a heat sink when running the generator. In that case, adding a backup heater (burning hydrogen, say) would make the store double as a backup generator at extremely low extra capital cost.

Re: Vertical farming does not save space

#430

Post by pfdietz »

sir_bearington wrote: post #345
strken wrote: post #317

Earlier quoted context omitted.

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 princ…

Biomass has low energy density, but that has nothing to do with non-biomass renewable sources, or with storage. The implication that the low density of biomass carries over is a deception.

The argument that nothing that hasn't been commercialized can be considered is a double standard. Nuclear on the scale needed to replace fossil fuels is also currently impossible. The infrastructure to build it isn't there, and the breeder reactors that would be needed to fuel it aren't commercially available either.

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