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Vertical farming does not save space

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Re: Vertical farming does not save space

#171

Post by dale_glass »

Andrew_nenakhov wrote: post #160
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…

To make nuclear energy successful you need to stop fear mongering, and invest in improving technology. With scale, it will make far cheaper and reliable energy source than anything on earth. But it will hardly happen when politicians tirelessly promote solar & wind, while increasing the regulation of nuclear energy. And politicians act this way because of said fear mongering, which affects the public deeply.

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?

Re: Vertical farming does not save space

#172

Post by ryder9 »

falcolas wrote: post #78
kibwen wrote: post #63

Earlier quoted context omitted.

> plants are more efficient at capturing energy from the sun than solar panels -> light bulbs -> plants are This is a counterintuitive misconception that I mention elsewhere in this thread. Plants aren't optimized for raw sunlight utilization, because that's not the bottleneck for growth or survival. Plants deliberately reflect away 90% of the sun's energy ( https://en.wikipedia.org/wiki/Photosynthetic_efficiency ) b…

> deliberately reflect away 90% of the sun's energy They'll have that same efficiency with artificial lighting too… At least until our grow lights stop emitting light in the green spectrum (not something I expect to see anytime soon).

almost like the people who designed growlights knew that and the technology that limits spectrums useful to plants has existed for at least a decade or more

with LEDs now they're even more efficient

Re: Vertical farming does not save space

#173

Post by tshaddox »

mytailorisrich wrote: post #150
Retric wrote: post #116

Earlier quoted context omitted.

Commercial nuclear takes up a lot of space, to the point where replacing it with solar is surprisingly close. For example the the Brunswick nuclear power plant in North Carolina, covers 1,200 acres or 4,860,000 square meters for 1,858 MW = 382 w/m2. It’s stated lifetime capacity factor is 75% which is much higher than solar, but that’s ignoring the long construction and decommissioning process afterwards. You can fin…

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…

But surely they don’t just own the “nature” land for the fun of it. I assume it could not be used for other things, like housing, or another nuclear power plant!

Re: Vertical farming does not save space

#174

Post by kristopolous »

kumarski wrote: post #111
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…

Way overshooting the confidence on fusion here.

It's placing something that quite literally simply does not exist on the balance sheet.

A physicist who died 55 years ago said it'd be commercially deployed by 1975. 1954 was the "too cheap to meter" claim by an investment banker who worked for the Truman administration. That's still quoted today, said 2 years before Elvis debuted on Ed Sullivan.

We're all supposed to treat it like it's a valid opinion. While instead, 46 years after the predicted free energy for all bonanza, rate payers are getting hit with taxes to keep nuclear going. It's in practice, in actual reality, a more expensive option.

Continue to research. March on with science, sure. But as a matter of public policy and planning, relying on it is pure fantasy.

I don't know why hn is so koolaid-drunk on this stuff. It's a cult with 70 years of failed predictions. It's apparently like any other cult where wrong predictions make the true believers even more fanatical.

We're amidst planet altering climate change, this is really not the time to fuck around.

Re: Vertical farming does not save space

#175

Post by falcolas »

kibwen wrote: post #143
falcolas wrote: post #78

Earlier quoted context omitted.

> deliberately reflect away 90% of the sun's energy They'll have that same efficiency with artificial lighting too… At least until our grow lights stop emitting light in the green spectrum (not something I expect to see anytime soon).

Grow lights are quite good at only emitting light in certain parts of the spectrum, and have been for some time now.

Just looking at some spectrum charts for grow lights... They certainly vary, but not in any uniform fashion.

There is an exception to this: there is a standard LED graph which shows up quite frequently, identified by it's peeks in the deep reds, yellow, and dark blue, with a marked trough at cyan.

Re: Vertical farming does not save space

#176

Post by pier25 »

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…

Woah great video. Thanks for sharing!

Re: Vertical farming does not save space

#177

Post by hansvm »

dragontamer wrote: post #140
hansvm wrote: post #123

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". I think what they were getting at is that you can take land wholly unsuitable for farming or greenhouses (e.g. severe slopes), apply solar panels, and then funnel that energy to a vertical farm. Since t…

> Since the vertical farm does save space in the abstract (just not necessarily once accounting for space needed for electricity generation) I severely doubt that. Solar panels are maybe 30% efficient. So 10-acres of glass-roofs need to be replaced by 30-acres of solar panels just to account for this inefficiency (let alone other inefficiencies: such as wiring, inverter, batteries, and LEDs). Maybe 50-acres of solar…

I'm not sure if you noticed, but your argument is that I'm not doing a good enough job accounting for the space needed for solar, and the thing you're trying to counter is that if you _ignore_ the space needed for [solar] then vertical farming makes sense. Those are two completely logically independent ideas which can't be used to refute each other regardless of their respective veracities.

Re: Vertical farming does not save space

#178

Post by notatoad »

marshray wrote: post #80
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…

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?

Re: Vertical farming does not save space

#179

Post by msla »

dragontamer wrote: post #113
tux1968 wrote: 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.

> 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…

> "Plant things in the ground" is also cheaper, though it does suffer from potentially poor soil conditions.

"Poor soil conditions" to include "soil" that is alkali dust, sand, dry for eleven months out of the year, frozen solid and under multiple feet of snow for more than half the year, and so far from either a river or reliable groundwater that any and all water used must be trucked in. In tanks. On trucks.

Plus, you only get to dump more fertilizer in the water if you filter it back out again.

Re: Vertical farming does not save space

#180

Post by notriddle »

Misdicorl wrote: post #31
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…

Even more to the point- solar panels live quite easily on roofs, deserts, highway medians. Quite a bit tougher to put functioning agriculture in these places!

Green roofs are a thing, though. https://en.wikipedia.org/wiki/Green_roof
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