Vertical farming does not save space • Hacker News Board

Re: Vertical farming does not save space

#441

Post by pfdietz » Sat, Feb 20, 2021, 2:54 PM UTC

cecilpl2 wrote: post #410

officehero wrote: post #350

Earlier quoted context omitted.

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

This is mostly because it has not been funded to the level required for that timeline to be accurate. https://upload.wikimedia.org/wikipedia/commons/a/ab/U.S._his...

Funding at the level in that chart would not have given us fusion. That chart is based on a crash program to develop tokamaks, but assumed tokamaks work better than they actually do. The main product of that crash program would have been tears and frustration, not practical fusion.

One can turn this around and say that fusion not getting the funding in that chart is evidence it was not seen as a promising place to invest. One cannot simply presume it's a good investment and ignore any evidence to the contrary.

Re: Vertical farming does not save space

#442

Post by pfdietz » Sat, Feb 20, 2021, 2:58 PM UTC

SECProto wrote: post #412

matkoniecz wrote: post #344

Earlier quoted context omitted.

"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".

> But compare it to [perpetual motion or faster-than-light space travel]. That's a completely inaccurate comparison - perpetual motion and faster-than-light violate fundamental physical laws as we understand them. Net-positive power from fusion is fully within the laws of physics – we've got an example in the daytime sky, and trillions in the nighttime sky. The difficulties with fusion come with shrinking it to a sca…

What fusion does is come close to ignoring the laws of engineering and economics. That's not quite the same as ignoring the laws of physics, but either of those is capable of rendering a technology a nonstarter.

Specifically, for fundamental reasons DT fusion will have much lower power density than a fission reactor, and so have to be much larger, and therefore have to be much more expensive.

Re: Vertical farming does not save space

#443

Post by pfdietz » Sat, Feb 20, 2021, 3:00 PM UTC

exporectomy wrote: post #226

benjaminjackman wrote: post #157

Earlier quoted context omitted.

I don't know about commercial by 2030 but leap frogging ITER doesn't seem far fetched at all because of the all signficant advances in superconductors achieved after ITER was planned out. Also, if the new superconductors do work out, it's very likely that all other forms of energy generation and grid level storage will become almost immediately obsolete and any additional focus moving forward would be only on improvi…

What makes you think fusion power will be cheaper than solar, wind, fossil fuels or fission? Efficiency isn't really a good metric when the fuel is free. We see that in solar power where expensive high efficiency devices lose out to cheaper less efficient ones. It's more about capital cost and operating cost per unit of energy.

Efficiency is also a bad metric if the inputs are different.

Usually when I see "efficiency" used in a pro-nuclear argument it's not used in any rigorous way, though. It's just a vacuous cheer word.

Re: Vertical farming does not save space

#444

Post by [deleted] » Sat, Feb 20, 2021, 3:03 PM UTC

selectodude wrote: post #409

southerntofu wrote: post #399

Earlier quoted context omitted.

> But is it more expensive than... Like you, i don't believe price to be an argument of concern. I'm merely stating this because over and over, both in French media and on HN, i've seen stated that nuclear is the cheapest energy which is a blatant lie. > We can reprocess the waste to make more energy with. Source? From my limited understanding, all nuclear research that produced either less-dangerous waste or re-usab…

>Source? From my limited understanding, all nuclear research that produced either less-dangerous waste or re-usable waste was shut down decades ago because there was no foreseeable way to turn that into weapons. The nuclear industry is deeply tied to the military industrial complex and (neo)colonial extractivism (see Françafrique networks for references). The existence of La Hague site in northwest France has been ve…

[deleted]

Re: Vertical farming does not save space

#445

Post by Andrew_nenakhov » Sat, Feb 20, 2021, 5:17 PM UTC

pfdietz wrote: post #428

Andrew_nenakhov wrote: post #406

Earlier quoted context omitted.

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 maturi…

For the past 40+ years there was an non-stop ongoing attack on nuclear energy. See "china syndrome" for more info.

Fear-mongering is _the reason_ for the absence of progress and rising prices, not some technical obstacles.

Re: Vertical farming does not save space

#446

Post by exporectomy » Sat, Feb 20, 2021, 9:17 PM UTC

pfdietz wrote: post #443

exporectomy wrote: post #226

Earlier quoted context omitted.

What makes you think fusion power will be cheaper than solar, wind, fossil fuels or fission? Efficiency isn't really a good metric when the fuel is free. We see that in solar power where expensive high efficiency devices lose out to cheaper less efficient ones. It's more about capital cost and operating cost per unit of energy.

Efficiency is also a bad metric if the inputs are different. Usually when I see "efficiency" used in a pro-nuclear argument it's not used in any rigorous way, though. It's just a vacuous cheer word.

Yes. Even fossil fuels contain far more nuclear energy than chemical energy so the engines we use are ~0% efficient if you actually count that as part of the input, even though we could, in principle, build an engine which does use it. How then do you compare two different nuclear fuels for efficiency?

Re: Vertical farming does not save space

#447

Post by Aeolun » Sun, Feb 21, 2021, 1:22 AM UTC

a1369209993 wrote: post #311

Aeolun wrote: post #266

Earlier quoted context omitted.

Wait, are you saying we know how to build a World Wonder that produces infinite energy, but we’re not doing it? What’ll we do if Ghandi builds it first?

Because we don't have enough energy demand to make it worthwhile. Even if we had enough money (and political will) to fund it, we'd be better off spending it on a space elevator, since we can actually use that enough to cover the costs.

With the only issue being that we don’t actually know how to build a working space elevator yet. Last I heard anyway.

Re: Vertical farming does not save space

#448

Post by pfdietz » Sun, Feb 21, 2021, 1:25 AM UTC

exporectomy wrote: post #446

pfdietz wrote: post #443

Earlier quoted context omitted.

Efficiency is also a bad metric if the inputs are different. Usually when I see "efficiency" used in a pro-nuclear argument it's not used in any rigorous way, though. It's just a vacuous cheer word.

Yes. Even fossil fuels contain far more nuclear energy than chemical energy so the engines we use are ~0% efficient if you actually count that as part of the input, even though we could, in principle, build an engine which does use it. How then do you compare two different nuclear fuels for efficiency?

You don't compare them for efficiency. That's a useless thing to do. You compare for other metrics that actually matter, like cost.

Re: Vertical farming does not save space

#449

Post by pfdietz » Sun, Feb 21, 2021, 1:28 AM UTC

Andrew_nenakhov wrote: post #445

pfdietz wrote: post #428

Earlier quoted context omitted.

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 maturi…

For the past 40+ years there was an non-stop ongoing attack on nuclear energy. See "china syndrome" for more info. Fear-mongering is _the reason_ for the absence of progress and rising prices, not some technical obstacles.

Fear mongering must be incredibly powerful, if it has universally stopped nuclear from getting much (or at all) cheaper, everywhere in the world, in multiple cultures.

Much more plausibly, the technology itself is to blame.

Re: Vertical farming does not save space

#450

Post by sir_bearington » Sun, Feb 21, 2021, 1:32 AM UTC

dale_glass wrote: post #427

sir_bearington wrote: post #415

Earlier quoted context omitted.

> 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 real…

> If you simply impose a carbon tax, private enterprise will just go and build solar.

Depends on how high the carbon tax is. Put it at a high enough rate that the country needs to go 100% carbon-free and people will build nuclear because that's the only solution (besides geographically limited things like geothermal and hydro) that can feasibly bring carbon emissions to zero.

Renewables are cheap when going from a mostly fossil fuel grid to a 50/50 renewable and fossil fuel grid. But bringing fossil fuels below 50% without the help of nuclear or hydroelectricity is extremely difficult. Any plan to do so basically assumes that some future breakthrough will make storage cost a fraction of what it does today.

> We have no storage? Those companies won't care. It's not their problem to solve.

Yeah, that's why there's no plan to actually decarbonize with renewables.

And if we actually want to stop climate change, yes it absolutely a problem that needs to be solved.

> 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.

Pass a carbon tax such that building a nuclear plant is less expensive than running solar during the day and natural gas at night. Renewables depend on fossil fuels until we make a breakthrough in storage.