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 Post subject: LFTRs and Food
PostPosted: Oct 11, 2014 8:39 pm 
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This site has stories about cheaply manufacturing molten salt reactors in a factory per a standard design. This site has posts about desalinating water. I would presume that some of the water will be used for agriculture. Having irrigation from this water means you no longer have to depend upon the randomness of rain.

I did a quick search and didn't see the exact topic which follows.

For those of us who have lived in lands of short growing seasons when you can barely grow sweet corn and barley may be your best bet for grain we know that another important variable is the sun. Molten Salt reactors may mean cheaper electricity. Could it be of low enough cost that hydroponics could become more prevalent? People today are in favor of locally grown produce. Farmer's markets are quite popular. Well, folks, there are some places that pineapples and bananas just won't grow and so aren't locally grown.

Could the LFTR make it possible to grow these crops anywhere? Large heated greenhouses and grow bulbs could coax these tropical plants into feeling right at home. The long shipping distances from banana republics and the interference in their politics would be a thing of the past. Fresh locally grown lettuce and other locally grown vegetables could be readily available all year long. Good food is an enhancer to good health. This food would be grown in a controlled environment and should be less subject to insect and crop disease problems.

If LFTRs are cheap enough and regulations are made reasonable, couldn't a group of farmers form LFTR co-ops to build LFTRs for agricultural use? What do you think? Will the capital costs of the bulbs, greenhouses, pumps, etc always be too high to compete? Some people pay a premium today for organic food. Could this hydroponic food be "sold" in a similar manner?


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 11, 2014 9:00 pm 
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All true. This is the pinnacle of all nuclear training, which cheap energy solves water and food shortages that solves population growth, while giving people the health advantages that cheap and abundant electricity does helps reduce population growth.

And that nuclear is the only very low CO2 emissions energy source that provides reliable baseload energy to achieve that without climate change.

I don't mean to rain on your parade. The benefits are clear. But how we solve the radiophobia, regulatory and funding issues is a far more effective usage of our time.

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 Post subject: Re: LFTRs and Food
PostPosted: Oct 11, 2014 9:38 pm 
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While it might not be feasible to use it for hydroponic use there is another way to get food from very cheap electricity.
First use fire calcium carbonate to produce lime and pure carbon dioxide (this works out as a very cheap way to produce it as a matter of fact as it requires no huge collection infrastructure, and the lime can just be dumped at sea if necessary to counteract ocean acidification).

Then you use yet more electricity to put the carbon dioxide and some steam from the reactor through a gas-phase electrolysis cell that produces a syngas stream (such electrolysis systems being available today).
This syngas is then fed to a fairly standard methanol plant that will produce high grade methanol.

This methanol, after distillation to ensure it contains no significant contaminants like DME or similar, is used inside an air-lift fermenter to grow cultures of bacteria such as Methylophilus methylotrophus or Methylococcus capsulatus.
These bacteria are then harvested and processed using yet more steam and electricity from the reactor to produce a product which can be used as a very very high protein content animal feed. It can also be used to manufacture materials similar to Whey Protein which can be useful in a human diet for supplementing otherwise nutritionally weak foods.

I have run variations on those numbers numerous times and if electricity prices can get into the 1-2 cent/kWh range it becomes highly competitive for use in a variety of animal feed applications (displacing Soybeans).
Even at 5 cents/kWh it can probably compete with high grade fishmea which is increasingly short supply.

So while you might not be able to grow things under artificial light, you can certainly raise livestock without having huge fields of protein feeds. I came up with figures that suggested something like one square kilometre of reactor and factory complex replacing a hundred thousand square kilometres of land under cultivation.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 12, 2014 12:09 am 
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E Ireland wrote:
While it might not be feasible to use it for hydroponic use
I've often thought that a monochomic LED source could drive photosynthesis efficiently. Just a thought.

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 Post subject: Re: LFTRs and Food
PostPosted: Oct 12, 2014 2:43 am 
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The basic problem is the "big" foods, the staple foods such as potatoes, rice, and grains. These must be produced very cheaply. The cost structure of hydroponics is so high it would be difficult to do even with 1 cent/kWh electricity.

Smaller volume foods and fruits can make sense in a hydroponic arrangement, but that's not where the "food" problem is.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 12, 2014 7:42 am 
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Displace Soybean and fish meal for animal feed and you drastically cut the amount of land required to support the human population.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 13, 2014 1:24 am 
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IAEA has a food and agriculture program involving many aspects but not hydroponics.
http://www-naweb.iaea.org/nafa/fep/index.html
Indian DAE has similar programs the most impressive of which to me have been mutational plant breeding and food preservation. It is nice to have ideas floating around some of which cold work in future. Water desalination is already developing constantly, both for drinking and agriculture.
http://dae.nic.in/writereaddata/gc2014_0.pdf


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 29, 2014 5:01 pm 
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I ran some numbers on this when I first read about vertical farms, Despommier's answer to a farmland shortage.
Given nuclear power, if interest rates are near zero, vertical farming is a great idea.
The issue is that the interest costs multiply all through the project: the structure, energy, and other infrastructure.
Another issue is that in some of the early vertical farm project descriptions, the farm appears to be a perpetual motion machine, generating mor eenergy than it uses.
This can only work if it uses sunlight, and if it does, then most of the land use and cost advantages are lost.

The main cost is the building. The interest can easily reach 5x that, depending on the rate.
Another big cost is the cost of electricity.

LED lamps do indeed help a lot with energy prices; Only about 10% of sunlight is nutritious for plants, and LEDs can make just nutritious wavelengths, and do so more efficiently than other lamps.

When I made pessimistic assumptions, e.g. union labor, market interest, market electricity, equivalent fertility to dirt farming, normal fraction of meat in the diet, I got costs near $35 per meal. This is the cost of the raw food, by the way, not a restaurant meal.

When I made optimistic assumptions, e.g. market labor, subsidized government loans, nuclear electricity at cost, a modest 4x improvement in fertility, and a vegan diet, I got costs down around $1.20 per meal. This seems high for raw food (market rates are near $0.35), but not impossible.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 29, 2014 8:49 pm 
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If you are growing grains you would use the super-dwarf strains like 'Perigee' or 'Apogee' Wheat, developed by NASA for use in spaceflight.
They are optimised for continuous-light growing, have less non-crop biomass and also have the benefit that since they are so short 'trays' can be stacked several high per story - which reduces building costs.

Methanol raised bacterial feeds would replace all grains and beans in livestock feeds I would imagine.
Additionally you can feed ruminants surprisingly crude feeds like triacetin or even ethylene glycol in significant quantities without much issue.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 30, 2014 4:32 am 
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Synthetic hydrocarbons and vitamins are already in use. Amino-acids could be conceivably be synthesized. Synthetic nitrogenous fertilizers are also in widespread use. Energy for manufacturing them could be nuclear. Things could always be taken further.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 30, 2014 12:37 pm 
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Food skyscrapers are currently for dreamers only, they may make sense in the future for high end foods like high end fruits and vegetables, but that is not where the "food problem" is. It is in the field of staple foods that big gains must be made, and the cost structure of sky scrapers isn't in the same realm as conventional agriculture.

Likely conventional agriculture, no LEDs or food skyscrapers or other such fancy things, will be good enough. Continued improvements in crops, terra preta/soils and the like will be good enough to make enough food for 10-12 billion without needing much more land.

Its amazing how much land is being used for extensive agriculture, no fertilizer, no irrigation, totally inefficient.


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 Post subject: Re: LFTRs and Food
PostPosted: Oct 30, 2014 8:38 pm 
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"Likely conventional agriculture, no LEDs or food skyscrapers or other such fancy things, will be good enough."

Sounds like the building is the most expensive part of this alternative way of producing your dinner. Get rid of the building. Install the facility in an old mine. There will be plenty of storage and perhaps the nuclear reactor could also be in the mine. It will not feed the world, but may produce fresh crops for a local area throughout the year.

Every place has certain advantages. The Pacific Northwest has hydro electricity. California has sunshine. Perhaps the people who have "worked out" underground mines have an advantage that hasn't been utilized. This is an industry that is both sustainable and sustains its customers. :P


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