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Japanese firm to open world’s first robot-run farm

theguardian.com

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Re: Japanese firm to open world’s first robot-run farm

#81

Post by lhopki01 »

vectorjohn wrote: post #30
thescriptkiddie wrote: post #20

Earlier quoted context omitted.

If the electricity for the grow lights is produced locally via solar power, it is actually more efficient than using sunlight directly (provided LED grow lights are used). This is because the grow lights provide only the narrow bands of wavelengths that plants absorb most efficiently. Only about 45% of visible sunlight is usable by plants, compared to around 95% for photovoltaics, which more than makes up for convers…

I don't know if that actually works in practice. Aren't photovoltaics (commercially feasible ones) like 20% efficient? Sure, its 20% of a bigger spectrum, and plants aren't perfectly efficient either, but I don't know if the math quite works as well as you make it sound. The other benefits are awesome though. And our fusion future will make the photovoltaics issue moot anyway :)

Plants are around 2% efficient.

Re: Japanese firm to open world’s first robot-run farm

#82

Post by dwc »

lhopki01 wrote: post #80
ValleyOfTheMtns wrote: post #31

Earlier quoted context omitted.

>and the decision to use grow lights indoors instead of sunlight This is the part of indoor automated farming I don't get. You have this free, abundant source of energy needed to grow plants, and you don't use it... why? Seems like a massive inefficiency. Indoors is fine to protect the crops and control the environment, but why not above ground with a clear roof to let sunlight in?

Most plants photosynthesise on a very narrow band of light. It's actually more efficient to generate electricity using solar panels and reemit using specific wavelength leds. Plants are around 2% efficient while solar panels are around 20%. Also as has been said below it allows you to stack plants in a way that would be impossible if you were using sunlight. Additional thoughts are that greenhouses are terrible at re…

People still do good things with greenhouses. I recently watched a video from a guy growing veggies through the winter in his greenhouse. He did have a non-glass southern wall but it wasn't the type for storing heat. Instead, he was using drums of water inside the greenhouse as thermal mass, which kept the temperature up during the night.

Re: Japanese firm to open world’s first robot-run farm

#83

Post by Retric »

lhopki01 wrote: post #80
ValleyOfTheMtns wrote: post #31

Earlier quoted context omitted.

>and the decision to use grow lights indoors instead of sunlight This is the part of indoor automated farming I don't get. You have this free, abundant source of energy needed to grow plants, and you don't use it... why? Seems like a massive inefficiency. Indoors is fine to protect the crops and control the environment, but why not above ground with a clear roof to let sunlight in?

Most plants photosynthesise on a very narrow band of light. It's actually more efficient to generate electricity using solar panels and reemit using specific wavelength leds. Plants are around 2% efficient while solar panels are around 20%. Also as has been said below it allows you to stack plants in a way that would be impossible if you were using sunlight. Additional thoughts are that greenhouses are terrible at re…

First, sugar cane converts 8% of the light absorbed by the plant is preserved as chemical energy.

Second, photosynthesis is actually fairly efficient, the issue is plants are living organisms and we only care about energy stored not energy used. Net result, plants still need about 45% of sunlight even if you stick with the 'perfect' bands.

Re: Japanese firm to open world’s first robot-run farm

#84

Post by agumonkey »

rorykoehler wrote: post #77
ValleyOfTheMtns wrote: post #31

Earlier quoted context omitted.

>and the decision to use grow lights indoors instead of sunlight This is the part of indoor automated farming I don't get. You have this free, abundant source of energy needed to grow plants, and you don't use it... why? Seems like a massive inefficiency. Indoors is fine to protect the crops and control the environment, but why not above ground with a clear roof to let sunlight in?

You can stack fields so you grow 20X the amount per square meter/foot/whatever than you would with sunlight. True there are vertical solutions that use mirrors but these become unwieldy to design and maintain (cleaning the dust off the mirrors etc) so it's simpler to just go with the led shelf solution. Adding to that, this allows you to grow vast amounts of food in urban environments meaning that it is a cheaper/sho…

I could see a more distributed food production, avoiding the production madness on natural soil. So country side could be countryside again, farmers could get a healthier life style while cities get cost less food with less pesticides too. I also wonder if this would be interesting on a per-house basis.

Re: Japanese firm to open world’s first robot-run farm

#85

Post by lhopki01 »

Retric wrote: post #83
lhopki01 wrote: post #80

Earlier quoted context omitted.

Most plants photosynthesise on a very narrow band of light. It's actually more efficient to generate electricity using solar panels and reemit using specific wavelength leds. Plants are around 2% efficient while solar panels are around 20%. Also as has been said below it allows you to stack plants in a way that would be impossible if you were using sunlight. Additional thoughts are that greenhouses are terrible at re…

First, sugar cane converts 8% of the light absorbed by the plant is preserved as chemical energy. Second, photosynthesis is actually fairly efficient, the issue is plants are living organisms and we only care about energy stored not energy used. Net result, plants still need about 45% of sunlight even if you stick with the 'perfect' bands.

Sugar cane is very much the exception. Most crop plants (which have over the years been selected for efficiency indirectly) manage 1-2%. No one is suggesting growing sugar cane indoors yet, just purely on the basis of it's height you won't gain much by stacking it.

Also you haven't addressed stacking, heat retention or for that matter nighttime light.

Re: Japanese firm to open world’s first robot-run farm

#86

Post by lhopki01 »

dwc wrote: post #82
lhopki01 wrote: post #80

Earlier quoted context omitted.

Most plants photosynthesise on a very narrow band of light. It's actually more efficient to generate electricity using solar panels and reemit using specific wavelength leds. Plants are around 2% efficient while solar panels are around 20%. Also as has been said below it allows you to stack plants in a way that would be impossible if you were using sunlight. Additional thoughts are that greenhouses are terrible at re…

People still do good things with greenhouses. I recently watched a video from a guy growing veggies through the winter in his greenhouse. He did have a non-glass southern wall but it wasn't the type for storing heat. Instead, he was using drums of water inside the greenhouse as thermal mass, which kept the temperature up during the night.

And people still grow plants by hand. The future is still going to be automated farms just as the present day is mechanised farms.

The advantages that automated warehouse farms give will be too great to not do. Faster grow cycles, no need for fertiliser, pesticides, or herbicides, closer to consumers, space efficiencies and so on.

Re: Japanese firm to open world’s first robot-run farm

#87

Post by ramy_d »

gozur88 wrote: post #74
ramy_d wrote: post #69

Earlier quoted context omitted.

Yes the transport issue is a big one for the US, however I'm talking globally. It's myopic to simply look at the US when talking about things that affect the US. The US doesn't grow its own food, and we should keep that in mind when reading stuff like this. Rather, I'm trying to take a look at these percentages of farming workforces by country: http://data.worldbank.org/indicator/SL.AGR.EMPL.ZS and trying to see what…

>The US doesn't grow its own food, and we should keep that in mind when reading stuff like this. Not sure what you mean by that. The US is a net food exporter by more than 70 million metric tons. Yes, other countries have more people in farming by percentage. But those people will be pushed out of farming by automation whether or not there are robotic farms.

> Not sure what you mean by that. The US is a net food exporter by more than 70 million metric tons.

you're right, http://www.fdaimports.com/blog/how-much-of-u-s-food-is-impor... but it doesn't change the matter of concern: what happens to those other countries' economic development when a large percentage of their workforce is rapidly made non-existent.

Re: Japanese firm to open world’s first robot-run farm

#88

Post by Retric »

lhopki01 wrote: post #85
Retric wrote: post #83

Earlier quoted context omitted.

First, sugar cane converts 8% of the light absorbed by the plant is preserved as chemical energy. Second, photosynthesis is actually fairly efficient, the issue is plants are living organisms and we only care about energy stored not energy used. Net result, plants still need about 45% of sunlight even if you stick with the 'perfect' bands.

Sugar cane is very much the exception. Most crop plants (which have over the years been selected for efficiency indirectly) manage 1-2%. No one is suggesting growing sugar cane indoors yet, just purely on the basis of it's height you won't gain much by stacking it. Also you haven't addressed stacking, heat retention or for that matter nighttime light.

The important point was Sugar cane is not better at photosynthesis than other plants. It simply 'wastes' less energy on growth and 'life'.

Break even would take 50% efficient solar collectors and 90% efficient lights including transmission and conversion losses. Clearly, we are nowhere near that point.

PS: The only reasonable option would be solar collectors that focus on different parts of the spectrum and let light through to the plants under them.

Re: Japanese firm to open world’s first robot-run farm

#89

Post by lhopki01 »

Retric wrote: post #88
lhopki01 wrote: post #85

Earlier quoted context omitted.

Sugar cane is very much the exception. Most crop plants (which have over the years been selected for efficiency indirectly) manage 1-2%. No one is suggesting growing sugar cane indoors yet, just purely on the basis of it's height you won't gain much by stacking it. Also you haven't addressed stacking, heat retention or for that matter nighttime light.

The important point was Sugar cane is not better at photosynthesis than other plants. It simply 'wastes' less energy on growth and 'life'. Break even would take 50% efficient solar collectors and 90% efficient lights including transmission and conversion losses. Clearly, we are nowhere near that point. PS: The only reasonable option would be solar collectors that focus on different parts of the spectrum and let light…

You don't need 50% efficient solar collectors. That'd be the case if 1 meter squared of plants had 1 meter squared of leaves. Even at full growth there are large gaps and for most of the growing time there are even larger gaps. 1 meter squared of solar panels is always going to be 1 meter squared. Also plants can't use light above 10,000 lux while solar panels will just generate more power.

And again how do you stack plants? How do you keep them warm enough? How do you grow them during the night?

Re: Japanese firm to open world’s first robot-run farm

#90

Post by Retric »

lhopki01 wrote: post #89
Retric wrote: post #88

Earlier quoted context omitted.

The important point was Sugar cane is not better at photosynthesis than other plants. It simply 'wastes' less energy on growth and 'life'. Break even would take 50% efficient solar collectors and 90% efficient lights including transmission and conversion losses. Clearly, we are nowhere near that point. PS: The only reasonable option would be solar collectors that focus on different parts of the spectrum and let light…

You don't need 50% efficient solar collectors. That'd be the case if 1 meter squared of plants had 1 meter squared of leaves. Even at full growth there are large gaps and for most of the growing time there are even larger gaps. 1 meter squared of solar panels is always going to be 1 meter squared. Also plants can't use light above 10,000 lux while solar panels will just generate more power. And again how do you stack…

Your solar collectors are not operating at night either. Break even means having 10 square miles of solar farm and 1 square mile of dense indoor farming needs to be more efficient than 11 square miles of farming and that extra needs to cover infrastructure costs.

You can play with the arrangements of plants in a greenhouse just as easily as a factory. EX: Stacking plants using clear trays and nutrient bath allows for using more light in the same space.

Anyway, the reason why this 'works' is crazy subsidies in Japan which actually has quite a bit of farm land, plus a market for ultra premium lettuce for decorative reasons.

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