Farm grows vegetables in a desert using sun and seawater | Hacker News Reader

Farm grows vegetables in a desert using sun and seawater

newscientist.com

543 pointsrmason184 comments

From OP:

> Sunshine and seawater. That’s all a new, futuristic-looking greenhouse needs to produce 17,000 tonnes of tomatoes per year in the South Australian desert

> The $200 million infrastructure makes the seawater greenhouse more expensive to set up than traditional greenhouses, but the cost will pay off long-term, says Saumweber. Conventional greenhouses are more expensive to run on an annual basis because of the cost of fossil fuels, he says

From the #1 google result for "cost of a ton of tomatoes" http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=15889:

> Processors agreed to pay growers $83 per ton in 2014, up from $70 per ton last year.

So assuming 100% profit margins (ie the tomatoes grow themselves, no human labor needs to be paid, nothing needs repairing or replacing, tomatoes deliver themselves to processing plants, etc, etc), the 17,000 tonnes produced would yield ~$1.4M annually. That's an awful (0.7%) annual return on $200M. Much less than you could get by investing the $200M in an index fund.

Which is to say there's a 0% chance it will "pay off in the long-term".

Well, it's in Australia...

> Average costs of production were up sharply for tomatoes to $843 per tonne

http://www.ausveg.com.au/resources/statistics/financial-perf...

wow, 10x more expensive? Well, 7% ROI isn't awful for them, though that's still assuming a 100% profit margins. If margins are less than 50% they're again losing to just investing in index funds.

It's also not unreasonable to assume that the cost of traditional ways to grow tomatoes will go up further, due to water becoming even scarcer, fossil fuel use being heavily regulated, etc.

But more importantly, the second of these plants will probably be cheaper than $200m, and the 50th will be a lot cheaper.

When the Ogallala Aquifer runs dry, America's vast everythingbasket will be finished. Even without fossil fuel regulations or even climate change itself, our unsustainable consumption will inevitably require solutions such as these.

Well the US also has some of the largest fresh water lakes in the world. I happen to live in Chicago right next to Lake Michigan (as a simple example). The Romans didn't have near the tech we have no a days and managed to create some impressive aqueducts. Given the extreme need, we would figure something out.

The Ogallala Aquifer has more water than Lake Huron and Canada has a rather large stake in the great lakes. So yes, it may add decades, but it's not a long term solution.

...but the rational, sensible solution would be ruined by NIMBYs and political corruption and horribly exploitative rent-seeking.

You almost have to fix the problem before anyone even realizes it is a problem to get it done at a reasonable cost.

There is one thing an index fund doesn't give you: food. So it seems logical to compare it to conventional greenhouses instead of comparing it to financial investments.

The food is the return on investment, so it is completely appropriate to compare it to a standard financial instrument. An index fund gives you money, which you can use to buy food.

You can only buy food if someone made that food, no?

There are a lot of tomatos grown is places that are not Australia.

Putting money in a financial investment ultimately means lending it to other people so they can make stuff, and it's perfectly logical to compare it against a production investment where you make stuff on your own.

Of course, if all tomato growers closed shop and put their money in index funds, we wouldn't have tomatoes any more. But that would make the price of tomatoes shoot up and the return on index funds crash down, making tomatoes a better investment than index funds.

> Of course, if all tomato growers closed shop and put their money in index funds, we wouldn't have tomatoes any more. But that would make the price of tomatoes shoot up and the return on index funds crash down, making tomatoes a better investment than index funds.

Unless, of course, angry hordes murder you because they tend to dislike people who watch famines as a normal market mechanism and suggest diversifying into cakes.

It seems a dick move to murder someone for not growing tomatoes when it's pretty easy for the mob to just grow the tomatoes themselves.

I thought the gist of the article was that it isn't easy to grow tomatoes in a desert.

Pretty sure it was a reference to Marie-Antoinette and the french revolution.

Yes, just poking a bit of fun at the detached-sounding wording.

I'm having a soft brain day it seems!

Funny, but unlikely. Farmers moving on to better-paying jobs is a process that takes decades, as we saw during the 19th and 20th century. It takes a sudden drop in the food supply to cause a famine.

Well, you're looking at the average cost to produce a ton of tomatoes. The average price received was 1,443 AUD (http://www.ausveg.com.au/resources/statistics/financials.htm).

How Sundrop Farms compare to the average production cost at 843 AUD/ton would be interesting though.

There seems to also be huge regional differences, in 2008 the price received for a ton of tomatoes was 224 AUD in Victoria and 1809 AUD in Queensland. (http://ausveg.com.au/LiteratureRetrieve.aspx?ID=86338)

There is also significantly less risk of the Tomato market crashing, and the potential to sell carbon credits if that becomes a thing in Australia.

Or, you know, the ideal notion that having a planet to spend $10 in is better than having a ruined hellscape to spend $11 in.

Don't just look at tomatoes, sea salt is very rich in minerals and that could also be extracted. If you where to locate closer to the sea in say the west coast of Africa it could be combined with aquaculture. I have been thinking about this for a long time actually

You'll also notice how they're premising stuff on realities that don't yet exist e.g. improvements in the design will make it fully independent from using the grid, or that it's a backup plan for when global warming makes current tomato growing areas unproductive.

There's a 0% chance that it will pay off in the long-term is true only if you assume that the current method of agriculture is sustainable in the long term, an assumption which I think is a bit of a stretch given the growing challenges we'll have to face. Of course, "long term" is not a very precise measuring unit, but it's still one I'd place my money on.

But the infrastructure cost of $200M can go down drastically on subsequent iterations, think how the cost of solar evolved past 5 years.

I'm thinking at this as proof of concept. If it works, there are many rich areas of the globe where fertile soil is at a premium and cannot grow much. Basically, transform oil dollars into local grown food.

Or places that lack oil dollars, but have plenty of land ruined due to desertification, a real problem in some parts of Africa.

> But the infrastructure cost of $200M can go down drastically on subsequent iterations, think how the cost of solar evolved past 5 years

So my $200M inestment will struggle to compete with a $40M investment in 5 years? That is a reason not to invest.

I find it weird this comment was downvoted but my post (GP) wasn't. I completely agree with you here MarkMc.

It's a $200M investment to own the company which will be taking $40M off someone else in a few years time to design and build their farm for them.

You should count those $200 millions as a sunk cost ... Sure you could buy index funds, but then, what do you have, more then a piece of paper ? If you have lots of money, it's much safer to buy "hardware".

Does it really works like that? If I invest 200 million in an Australian Index funds I''m exposed to all risks/rewards that the Australian economy faces.

If I invest 200 million in a greenhouse then I'm less exposed to all risks and rewards in the Australian economy (assuming that there's a weak correlation between the state of the economy and amount of Tomato's consumed, which seems reasonable) + all the risks in the Tomato business.

Now, it might be easier to insure against Tomato specific risks but I still don't think that the Tomato business (as awesome as this greenhouse sounds) is a clear winner here.

I imagine that the people funding this consider it a strategic investment with potential upsides beyond making as much money as possible over some arbitrary time period

Perhaps their long-term analysis accounts for reduced infrastructure costs due to economies of scale, increased food prices due to prevalent drought, and consulting / IP royalty fees due to having pioneered such useful technology.

> That's an awful (0.7%) annual return on $200M.

Is this really surprising in the world of agriculture? You get big loans to get a big lot of earth and pay it over multiple generations.

Those prices are for processing tomatoes. Not the kind of tomatoes you'd find at the grocer, rather the kind that will go into a bottle of heinz ketchup or a can of tomato paste.

They are grown differently and treated differently because appearance basically doesn't matter. They're also not required to be available for retail year round. They'll be processed within days of harvest in the fall.

Greenhouse in the desert can't compete with processing tomatoes. What they can compete is with the green house tomatoes sold in grocery store in the middle of winter.

Sometimes things are worth doing even if they don't represent a fantastic investment opportunity that will certainly outperform the market. Perhaps if you take into account the negative externalities of growing food in a desert - or worse, shipping it in from another part of the world - the cost benefit analysis reads a bit better.

You're assuming that this method is the final product. This is pretty clearly a research effort that can be built on, adjusted, etc.

That's for bulk field-grown tomatoes. Canadian greenhouse tomatoes sell for around USD1-3/kg (depending on variety, size, season &c.) which is $1000-3000 per metric ton, or 17-51M USD gross.

Also the article is unclear if the $200M investment is in USD or AUD, which makes a fairly significant difference.

200M is probably including a lot of research. I expect a duplication of this place to be much cheaper.

Seems like this idea is couple of decades in making..

A seawater greenhouse is a greenhouse structure that enables the growth of crops in arid regions, using seawater and solar energy.

The technology was introduced by British inventor Charlie Paton in the early 1990s and is being developed by his UK company Seawater Greenhouse Ltd.

The technique involves pumping seawater (or allowing it to gravitate if below sea level) to an arid location and then subjecting it to two processes: first, it is used to humidify and cool the air, and second, it is evaporated by solar heating and distilled to produce fresh water. Finally, the remaining humidified air is expelled from the greenhouse and used to improve growing conditions for outdoor plants. https://en.wikipedia.org/wiki/Seawater_greenhouse

Making Namibia’s desert green using seawater https://www.newera.com.na/2016/07/08/making-namibias-desert-...

> On a sunny day, up to 39 megawatts of energy can be produced – enough to power the desalination plant...

They don't appear to be using evaporation and distillation, but instead generate electricity and run the desalination plant with that... I'm guessing, by pressured osmosis, as used elsewhere in Australia.

My question is: why don't they do it as you assumed? Whatever a solar still might lose in efficiency, it must surely make up in the reliability and simplicity of no moving parts.

During the pilot project Sundrop decided to simplify the design. The equipment for the distillation of the hot humid air proved to be complicated to produce with the resources available at the time and they decided to go with a more conventional method.

Personally I think the original design could be made to work, but it needed more R&D than Sundrop was prepared to spend at the time.

Indeed, trying too many new processes all at once would be setting yourself up for failure. Now this works, the other parts can be addressed and further efficiencies made.

There's a great video on youtube about the Advanced Passenger Train in Britain in the 80s where they tried a few too many new things with predictable results.

I can't help but imagine this technique being handy when settling on or terraforming certain planets.

Certain planets with an abundance of salt water?

Or flooding them with such, first? Not that I know which currently-known planets we could do that on.

Thermonuclear bomb the Mars ice caps. I think I read that in a scifi book.

Mars is really cold. At the equator the thin atmosphere can heat up reasonably at noon, but it still hits minus 100f at night even at the equator.

There are subterranean brine rivers on mars so large that they can be seen from orbit.

https://www.nasa.gov/press-release/nasa-confirms-evidence-th...

Not quite. Here is a link that's probably easer to understand.

https://science.nasa.gov/science-news/science-at-nasa/2000/a...

We are not looking at underground water in those pictures we are looking at evidence of likely very short term water causing a tiny amount of erosion in just the right situation. However, it's long been known there is actually quite a lot of ice on Mars.

Slam a shitload of comets into it, like in Seveneves.

If you include moons, plenty of water on Europa, though don't know if it's salt water. Generally I'm against terraforming though, especially because we've not shown we can be good custodians of our home planet.

  Generally I'm against terraforming though, especially because we've not shown we can be good custodians of our home planet.

Which to me doesn't logically follow. Send a few politicians to some $%^# hole of a terraformed moon and see how long it takes before they decide taking care of the earth is important. Second, we are basically terraforming earth, the problem is that we don't really have a clue what the outcome will be. Its the equivalent of giving a 5YO a soldering iron and a laptop and letting them play.

Just because we can and do terraform doesn't mean we should. I'm a big believer in appreciating nature for what it is rather than seeking to dominate it. The Sahara Desert is a great example... Imagine we could cheaply and effectively green the Sahara desert, why would we not want to do that? Perhaps because it adds to the diversity and richness of our world. If you only consider this practically then it makes no sense, as very little grows in the desert, so it's less useful than more fertile land, but when viewed as a cultural asset it absolutely makes sense to keep it relatively untouched by human influence.

This is a stark example, but it applies across the board. As I hinted at before, dominating something is less interesting than working with it.

> I'm a big believer in appreciating nature for what it is rather than seeking to dominate it.

Is a termite mound any less "nature" than some random patch of earth and rock? What about bird nests, beehives and beaver dams?

We are nature. The Universe is one continuous stream of change.

> "We are nature. The Universe is one continuous stream of change."

Sure, but we're not the only expression of nature that exists. By optimising a planet for the desires of one type of organism you do not necessarily optimise it for all living organisms. If we want to be good custodians of a planet we share with other organisms we should seek to balance our needs/desires with those of other organisms we live alongside. Due to our position on the planet at the top of the food chain due to our abilities gained through tools/technology we have a greater ability to influence the quality of life of fellow Earth inhabitants. Whilst nature can be seen as indifferent, humans are not indifferent about the world they inhabit. If it makes it more straightforward to understand, see it as selfishness... I want to live in a world with a rich diversity of life that can thrive alongside humanity because it makes life more interesting for me.

Where are the nutrients for plants coming from?

They say plants are grown in coconut husks instead of soil. Does the coconut husk act merely as a plant holder, or is it the one that provides the nutrients that the plant would otherwise obtain from soil (with/without fertilizer)? That part is not clear to me.

Edit: "There is no need for pesticides as seawater cleans and sterilises the air..." What does this even mean? Do we normally use pesticides to clean and sterilize the air? Are the pests that we fight with pesticides eliminated when the enclosed air in a greenhouse is cleaned and sterilized in this manner?

See comment here about the pesticides. The article is badly worded. https://news.ycombinator.com/item?id=12658321

Nutrients are added to the irrigation water.

But where do the nutrients come from? The things supplied by fertilizer are not free, which presumably is why the article made such a big deal out of not using fertilizer or soil.

Once the farm's in operation for a while, I'd assume they could compost a lot of the waste material picked up during harvesting. I'm not sure about tomatoes; are the plants destroyed during harvest and grown from seed each season? Some crops are certainly handled that way.

The plants will survive for more than 1 season but as practical matter they would be culled at the end of their productive period.

The stems and such are mostly water and a little bit of carbon, I guess other sources of nitrogen would have an excellent ROI (a modest amount of fertilizer vs high capital and labor costs).

I don't think hydroponics is a completely closed cycle, so there still has to be a source of nitrogen/ammonia

https://en.wikipedia.org/wiki/Nitrogen_fixation

which is ultimately very energy intensive

https://en.wikipedia.org/wiki/Haber_process

That was an enlightening read! I had no idea that humanity was so dependent on one process for so much of its essential existence!

If you think about the context in which we are operating though (desert with a lot of sunlight) it might be possible to colocate a solar powered reactor producing all the ammonia required for the hydroponic farms in the desert. This is just handwaving though: it seems like apart from electricity, the next biggest input is natural gas. While this may not be a problem in, say, Saudi Arabia, probably would be in Namibia.

With cheap enough power you can just tear the nitrogen out of the air.

https://en.wikipedia.org/wiki/Birkeland%E2%80%93Eyde_process

Hmmm I wonder if there would be a way to also grow green beans / soy beans, which always deposit nitrogen as a byproduct of their own growth. I have a mini urban farm in my teensy Chicago back yard and Rotate beans, cucumbers, and tomatoes to ensure the soil contains the right nutrients.

Have a look at this link, which I think I found on HN sometime ago. Hydroponics and fish working together in Detroit. www.modeldmedia.com/features/indoorurbanagriculture052014.aspx

or add an aquaponic cycle to solve the nitrate side of the equation (and yield fresh fish, to boot)

I added this link earlier which is following this idea, its a great story www.modeldmedia.com/features/indoorurbanagriculture052014.aspx

I love Detroit :D (btw Tilapia are illegal in Australia, they're extremely invasive, but there must be a local anlog)

In general the plant is discarded once a year. The growers normally get seedlings from a specialist that grows from seed.

The tomato plan contain mild toxic content, and is quite smelly so not even goats seem happy to eat it. Not sure what they actually do with composted tomato plants.

https://en.m.wikipedia.org/wiki/List_of_poisonous_plants

Leave it long enough to grow it into more tomatoes.

Tomatoes are ridiculously easy to grow from seed. If you let any tomatoes fall to the ground you are guaranteed to spend every year forever after dealing with hundreds of tomato plants.

Until you've got enough leaves and other detritus, there won't be any ground.

I hobby garden and also grow greens hydroponically. Greens are > 95% water weight. I think tomatoes aren't far behind.

when I first started with hydroponics I was amazed at how little fertilizer/nutrients needed to be added to the system to produce the volume I was producing.

I think with traditional farming a lot of fertilizer is lost to the environment which isn't so in closed hydroponic systems.

> I think with traditional farming a lot of fertilizer is lost to the environment which isn't so in closed hydroponic systems.

Do you have a cite on this for further reading?

https://en.wikipedia.org/wiki/Dead_zone_(ecology)

Among other factors, fertilizer runoff is a studied cause of substantial ecological effects. There's a huge rabbit hole to start you off.

I'm looking for something more quantitative.

I am also looking for someone to spoonfeed me information on random topics that momentarily take my fancy. Let me know if you find someone like that. I want to be their friend.

Most of the nutrition comes directly from seawater if they're smart, see SEA-90. I use it for most of my hydroponic plants.

I doubt the title is 100% accurate. They are definitely using outside fertilizers.

I have seen strawberries grown in coconut husks in Malaysia, apparently they do work like soil, with some extra advantages. The need of more or less fertilizer probably depends on what plant you're growing and which productivity targets you have.

> They say plants are grown in coconut husks instead of soil. Does the coconut husk act merely as a plant holder, or is it the one that provides the nutrients that the plant would otherwise obtain from soil (with/without fertilizer)?

The coconut husk is just an inert medium which has good water retention rate. The nutrients are supplied via water by irrigating the plants frequently or submerging the roots. The whole method of growing plants like this is known as hydroponics[0].

[0] If you are interested in hydroponics, this guy has a lot of amazing videos that explain various aspects of it - https://www.youtube.com/user/Just4Growers .

Also, if you're interested in hydroponics (especially indoor) and live within the US, be careful how you buy the materials needed to start. The police are known to profile these customers and raid the houses several months later [0].

[0] http://www.kansascitycriminaldefenselawyer.com/when-gardenin...

Looks like a reliable source to me!

That was just one of the more succinct sources I could find at the time. Here is an article from the Washington Post which details the subsequent lawsuit against the police department (which they lost).

https://www.washingtonpost.com/news/the-watch/wp/2015/12/28/...

sun, seawater .... and fertiliser.

As made clearer in other articles [1], they are adding nutrients to the water.

In response to delbel: As mentioned in [1], the farm has a 10-year contract with Coles, one of Australia's big supermarkets, and that was what enabled the farm to be funded. Consequently, you can go to Coles and buy these tomatoes for about A$7 per kg. [2]

[1] http://www.abc.net.au/news/2016-10-01/sundrop-farms-opens-so...

[2] https://shop.coles.com.au/online/SearchDisplay?storeId=10601...

Which ones are they? There's only one type of tomato not labeled 'product of Australia' on that page, and it's $23/kg. I'd love to pick some up when I go home tonight, just to try.

> sun, seawater .... and fertiliser. As made clearer in other articles, they are adding nutrients to the water.

Yes, that is how plants work.

Why so smarmy? The article specifically says "using only sun and seawater", so it's worth mentioning that they're also adding nutrients to the water. There are three necessary ingredients.

If the title was "using only sunlight and nutrients" or "using only seawater and nutrients" it would make sense to mention the third ingredient, so I'm confused at why you jumped straight to condescension.

Well if you want to get technical it also involves tons of pumps, solar panels, glass, etc. Obviously they weren't planting seeds in a puddle of seawater.

I was able to figure out it was a hydroponic setup from the headline and that the novel part was that they were powering desalination with solar power, not that they have figured out how to grow plants without any nutrients.

IDK, I am with jonkee here. Femto seems like the smarmy one to anyone who has some knowledge of biology.

It's really weird to be on a HN thread where most of the people don't know much about the topic, you get really weird pedantic posts seemingly out of nowhere. Biology and space seem like the most common ones, where people who are very smart point out missing details, the kind of missing details that are handwaved by the actual professionals and the kind of details that would turn an article like this into a textbook chapter.

A realistic possibility was that they are using the cheap energy to manufacture nutrients, such as ammonia, on-site, which is an energy intensive process [1].

[1]https://www.scidev.net/global/agriculture/news/solar-ammonia...

Another alternative is the seawater they're getting comes loaded with nitrates already from fertilizer runoff or naturally-occuring sources of nitrate leaching.

Aquaponics (fish + plants) is a more closed cycle, where the plants can feed the fish, and the fish byproducts can add plant nutrients to the water, if the right fish/plant combinations & balances are used.

If this greenhouse system did not require an external nutrient supply, that would also be a noteworthy innovation. Note that people are asking if the nutrients are coming from the coconut husks, or from composting leftover tomato plant matter, specifically because it only said sun & seawater are used. Anybody who grows anything is interested in reducing inputs to their plant systems, and greater feedback interactions among their biodiversity.

For those interested in these matters, the books by Masanobu Fukuoka (1) are a must. They may challenge some of the HN crowd views on progress, technology and religion, as they did definitely challenge mine, but they carry significative scientific truths. His focus on fighting desertification was both genius and ahead of his time.

(1) https://en.m.wikipedia.org/wiki/Masanobu_Fukuoka

The One Straw Revolution has been very inspiring for me. Highly recommended to anyone who wants to learn about natural farming.

Inspired me so much that I flew to Tokyo, caught an overnight ferry to Shikoku and then hitch-hiked across the island to visit his farm. Met the man and spent the day looking around the farm/orchard. It was very beautiful. Unfortunately he was then too old for me to stay longer (I'd had dreams of living and working on the farm). This was back in 1990.

Beautiful! If you have pictures and one day blog a few lines about this encounter, I'd be delighted to read it!

Thanks for your interest. I should write it up. I also visited an organic mikan farming co-operative not far from Fukuoka's farm on Shikoku and stayed there a few days. Actually he suggested it to me.

There are several things which aren't covered well in the article. I have spent quite a lot of time looking at the feasibility of the Seawater Greenhouse in multiple locations, including a visit to this Australian location a few years ago. [1] I haven't been involved since the pilot installation in Port Augusta, so they may have changed a few things described below.

The Seawater Greenhouse design is not a conventional greenhouse. It cools rather than heats a crop, it is an open design, rather than a conventional "closed" design.

The system, as designed by Charlie Paton, uses evaporative cooling in the greenhouse. Essentially they have a cardboard wall, sort of like a thick honey comb with holes through it, over which they pour seawater. The air is pulled through the wall by large relatively slow fans. When the air moves through the "honey comb" wall, the air changes direction (30 degree angle channels). Particles and insects in the air essentially get stuck in the seawater. Seawater is particularly bad for insects and other small pests as the salt clogs up the exoskeleton and the breathing channels when the water evaporates.

Even though the greenhouse was standing in an area of vegetation with a significant insect population outside, we hardly saw any insects on the inside. But you could often find quite a few insects in the seawater tanks used to hold the water for the evaporators. The stable climate created in the greenhouse and the seawater "barrier" created by the evaporators means the pest insect pressure is lie and you can easily control it with natural enemies (bio control). (There where poisonous spiders in the canopy of the crop but they don't affect the crop, but act as biocontrol. Just don't let them bite you.)

Plants grow much better in a cooler and high humidity environment. The plants don't have to put so much effort into transpiration to keep an acceptable temperature for photosynthesis. The evaporators with seawater handles both of those things.

The temperature during my visit peaked on Christmas Day at 43 C, but inside the greenhouse it was a much more acceptable 35 C. (We had our Xmas dinner just behind the evaporators, the most pleasant place in Port Augusta at that point.) The energy used for this cooling primarily comes out of the water and the surrounding air. Some energy is used for pumping water. Without the evaporative cooling the temperature in the greenhouse would have been at a level which would have killed the plants. During my visit the plants and crop grew so fast that we had to help harvesting to keep up.

The evaporators are also covered by sea salt, which is hydroscopic (absorbs water) which means that when the temperature drops at the end of the day you don't get water (dew) collecting on the plants. This is important as dew on the plants and produce allows botrytis (mold) to grow and potentially destroy the produce. This also avoids having to burn sulphur in the greenhouse to kill the mold.

[1] pictures from my wife during the visit https://www.flickr.com/photos/ankertje/7044271777/in/album-7...

Great comment, thank you (and thank your wife for the photos, fantastic to see some of the workings!)

Do you know how often the cardboard needs to be replaced?

It seems that it lasts a long time, at least several years. But, no, I don't really know.

Thank you very much for telling this story. I love HN for being filled with intelligent and interrested people from around the world. It feels very cool to be part of this community every time I read an insider story like yours!

Very cool.

P.S. The Wikipedia page for seawater greenhouses really needs some better photos. I've contributed to Wikipedia in the past but now lack the time/motivation, but if you or anyone has the motivation and permission, you could make the world a better place by adding some of these photos to Wikipedia.

What happens to the concentrated sea water at the end of the cycle? Does it get pumped back to the ocean? Deposited into the ground?

100% natural, environment friendly, organic non-GMO locally produced Australian salt!

How would one even make genetically modified salt? The most you could do is to add additional genetically modified compounds to the salt, but salt in and of itself cannot be genetically modified.

Could I check, is this gluten free?

Like with most desalination plants I presume they mix it back with seawater and deposit in the ocean.

Wow, that is a good story. BTW I liked the spider part -- can't have anything in Australia without deathly poisonous spiders? Check :)

Can you please tell us about the nutrition for the plants - is there some soil involved, or fertilizers?

The add fertiliser to the irrigation water. That is IMHO a mix of science and an art form to get that right in new conditions.

When I saw the headline I knew instantly how they did it. But the one thing unexplained in the story was their claim that the seawater piped in eliminated the need for pesticides.

I would bet it was the desert climate that reduced the need for pesticides. I am willing to predict that they will eventually need to use pesticides.

if the plants are inside a greenhouse, i think this is a major barrier to most pests.

Greenhouses can amplify pest problems as they are a closed system where things can get crazy very quickly with no natural checks and balances. They are some of the biggest consumers of pesticides.

Growing tomatoes one time under cover had a huge problem with white fly, not an unusual infestation, but a very stubborn one. While using the natural kinds may be better, pesticides are often a necessity in that situation. Your comment was completely on target for many commercial producers.

This may turn out to be a silly question, but how does a pest infest a closed system in the first place? Do they arrive in the soil? Do they fly in the door?

Could there be ways to mitigate or prevent the mechanism of infestation in the first place?

I imagine it boils down to a question of expense.

Pests can probably arrive through:

  - People's boots/clothes.
  - The water.
  - The soil/fertiliser.
  - The air.

Each of those inputs would need to be filtered. And the cost of filtration (or the entry/exit protocols for the workers) would need to be balanced against the cost of losing a crop.

Fungal spores are everywhere. And in hot humid high CO2 environment where there are no other kinds of fungal spores to compete with, and a big giant buffet of the kind of food they like...

Nom nom nom nom.

Same thing goes for insects.

Nature is constant warfare. Farming is like picking a side and arming it.

You also must contend with diseases. Mono cropping something like tomatoes is a good way to amplify them.

That's a problem if you re-use the same land again and again, but probably not so much when planting in regularly replaced coconut husks.

This comment explains it: https://news.ycombinator.com/item?id=12658321

Thank you, that really does explain a lot. If the economics are good I am surprised that this hasn't been tried in other places in the world.

Saudi Arabia installed center pivots in the desert to grow wheat back in the seventies. I believe at the time the US price of wheat was $3.00 per bushel and the Saudi's production cost was $12 a bushel but they still thought it was worthwhile to have some home grown wheat.

In case you missed the article from yesterday, which was also posted here, named "The Dizzying Grandeur of 21st-Century Agriculture":

http://www.nytimes.com/interactive/2016/10/09/magazine/big-f...

So, this is a hydroponic greenhouse. It would be neat if they went one step further and made it an aquaponic greenhouse. The use of salt water means they could consider growing saltwater fish (or shrimp, or fish for caviar). The only caveat is whether it would be easy to separate the salt from the water while keeping the other nutrients (nitrogen, etc) in the water for the plants.

I don't think it's been settled whether aquaponic setups are any more efficient overall than hydroponics when you consider all the inputs. A lot of it would depend on the local environment, the scale of your operation, and the availability of whatever you're feeding the water critters. It's more variety, though, which in itself is a nice thing.

Since this is a commercial enterprise, the question is not one of efficiency, but of potential profit. You're right that there are a lot of factors that would play into profitability.

If this catches your interests, please research greening the deserts using permaculture.

Here is one example but there are many examples and projects:

https://www.youtube.com/watch?v=D4Nb-rqGfWI&spfreload=10 | Reversing Desertification With Sticks, Rocks, and Ancient Wisdom

Permaculture is more practical in the long run, doesn't require much tech.

This. Looking at the headline I half expected this to be a permaculture installation.

>I think if we could get Earth in a living and stable state, not a constantly degrading and dying state caused by our actions, then we have won some right to go to the stars. But at present I don't think we'd be welcome anywhere else in the universe. You wouldn't welcome anybody who'd laid waste to their house and wanted to live in yours, I'm sure. -- Bill Mollison, Co-founder of Permaculture (4 May 1928 – 24 September 2016)

Perhaps we could colonize the deserts on earth before Mars.

When the next comet strikes, solar powered desert farms will be wrecked just as much as everywhere else on Earth.

Unless a Mars colony is completely self-sustaining it'll be just as wrecked as anything on this planet without the support of Earth. Considering the lack of raw materials available there, that'd be effectively impossible.

Elon Musk disagrees with you, for what it's worth: http://www.spacex.com/mars

Elon Musk doesn't even have a proof-of-concept for how we can set up a sustainable, closed biosphere-in-a-bubble on Earth - let alone Mars.

If he wants to put people on Mars in 8 years, this should have been a top priority a decade ago.

Sure, but comet can strike Mars just as easily as it can strike Earth. Maybe even more easily - gravity, lack of atmosphere, etc.

That's an interesting idea... I think the thin atmosphere and lack of ocean might actually make comet strikes on Mars less devastating than on Earth. Less frictional heating during the impact, no global tsunamis caused by an ocean strike, much less wind and shockwave around the impact site, faster settling of post-impact dust and debris. You wouldn't want to be near the impact site on either planet, but if you're far away on Mars you might barely notice it, while on Earth you could be on the opposite side of the planet and still be killed by a tsunami or shrouded in darkness until all the plants around you are dead.

The relevant issue is whether two comets could strike both Earth and Mars within the interval required for either one to recolonize the other.

I think that's one of the reasons Mars Colonization would be a great thing for humanity overall. The technology we would have to perfect to survive on Mars would be very useful back on Earth.

> no soil, pesticides, fossil fuels or groundwater

What about fertilisers? I would assume they still use conventional ones made from fossile fuels. Anybody got more information, did I miss sth in the article?

So it's basically a desalination process in a greenhouse powered by solar? I'm not sure why this is better than leveraging existing infrastructure to get freshwater and electricity. Also, farming somewhere other than a desert, then transporting the food to the population (if they live in a desert).

I guess it makes sense in places like SA, NT or WA, where, in 90% of their territory, all the alternative resources you mentioned are hard to get by.

There are plenty of economically unproductive coastal deserts in the world where this could be used.

Combine with this and we're golden

http://www.independent.co.uk/news/science/japanese-plant-exp...

For a headline that explicitly excludes the 3rd essential component of growing (light, water, nutrients), the article mentions nothing about how these plants are getting nutrients.

I assume they're supplementing liquid nutrients, as they're growing hydroponically in coco husks? If so, that makes the headline seem ridiculous...

The coolest thing in the story for me is using salty air to repel pests. Though I wonder about the longevity of that solution. I've never seen a bullet-proof solution to pest control, and especially in self-contained environments, it's usually just a matter of time. Nevertheless, makes me wonder about a saltwater humidifier....

Salty air is highly corrosive. Unless you want rust in every bit of iron in your furniture, that may not be the best idea.

The headline claim is demonstrably poorly researched and as others point out the project seems to be incredibly poor value.

There's a lower tech approach that's been extensively proven and in production since 1998, it produces not just veg, but firewood/biomass, shrimps, fish, fresh water and more:

http://articles.latimes.com/2001/jan/06/news/mn-9169 https://www.youtube.com/watch?v=_P1rPnVUME4

This would be awesome for Israel!

And if they could only fix their political problems (to put it mildly) Gaza as well. It could make a real difference in their future.

Israel has already made huge investments into desalination and has now more water than it needs.

More drinking water than it needs, but not more agricultural water - they could grow a lot more with extra water.

This method could help them do that.

Wow, simply wow.

Humanity is turning the world into farms, destroying natural forests but then engineering new types of habitats.

I wonder what the Earth would look like in 200 years.

What I am worried about is the rapid growth of the human population and its energy use. You can't have exponential growth forever. Most of the issues come from that. Farms and monocultures sound nice, but are they sustainable? Are the resources being recycled somewhere, or are we going to be plugging holes with bacteria digesting plastic and producing plant food?

Our problems come with growing consumption per capita than our number per se.

> You can't have exponential growth forever.

We don't. Look at the more developed nations.

> “It’s a bit like crushing a garlic clove with a sledgehammer,” he says. “We don’t have problems growing tomatoes in Australia.”

that's an epic way to miss the point completely.

This is fascinating. I grew up about 30 miles from the Salton Sea, which is in the middle of the desert of Southern California. We get tons of sun. I'd be very interested if these researchers are communicating with those investigating how to best clean up the Salton Sea. While those efforts are still in their infancy, there could be some overlap in application of the research.

Or instead of wasting energy trying to remove the salt, you could just use diluted seawater.

https://www.google.com/amp/s/amp.theguardian.com/science/201...

Well... you still need to have ready access to fresh-water to dilute seawater. This experiment is being done in a desert area where fresh-water is likely a high premium.

I wonder what they're doing with their desalination outflow? The prine produced during desalination can be nasty, toxic stuff: https://en.wikipedia.org/wiki/Desalination#Environmental

Why do they use concentrated solar power? Isn't that much more expensive and risky at current prices?

That's a good question. Also kind of an interesting side note: the company behind the solar technology here is not Sundrop, but they're not mentioned at all. Which I find really curious. I may have worked for that company 4 or 5 years ago. 100 points for whoever can name them!

...and most importantly, fertilizer

(this is covered in the article, but the headline forgets that part)

They built themselves a prime bird frying machine. Insects like heat, the birds follow them and voila, instant cooked meat! Extra bonus for this type solar.

Solar mirrors need to be extremely clean to be efficient. And that requires a lot of soap and clean water. Could it be a deal breaker in that kind of systems?

"The $200 million infrastructure makes the seawater greenhouse more expensive to set up than traditional greenhouses, but the cost will pay off long-term"

It's really nice experiment, but I don't see how that's gonna pay off. You need to sell a hell lots of tomatoes to earn $200 million back.

Rebrand it as a "Neural-network-AI-assisted seawater greenhouse". And VCs will fund your 200M$ in a minute.

You could've said the same about anything related to "web" in nineties and we know how it ends, sooner or later. That doesn't make something economically viable on the long run. I'm all up to self sustained, "green" farming in impossible places, but 200M$ for a moderate size greenhouse seems way too much to be something more than an experiment.

>First farm to grow vegetables in a desert using only sun and seawater

And Coconut Husks.

Just becomes something looks like a tomato, it doesn't make it one! In order to have nutritious produce, you need a lot more than just macro ingredients!

This should definitely be tried in the UAE!

To pay for the infrastructure, they will probably need to sell the tomatoes for $100 a pound for twenty years.

The beginning of most major scientific breakthroughs have high starting costs.

Well, the articles states the greenhouse is expected to yield 17,000 tonnes per year or 37.47 million pounds of tomatoes. The infrastructure costs 200 million dollars. So if they sell the tomatoes for $5.34 per pound they will pay off the infrastructure in a year. 53.4 cents per pound and they will pay off the infrastructure in 10 years. I expect it will be somewhere in between.

Pretty close though.

The video states they have locked in an exclusive agreement with a national grocery chain to provide tomatoes for 10 years at a fixed price. My guess is its a win-win for the respective companies.

Edit: Is my price right??? After posting I began to doubt it and I am having terrible problems trying to find out what the current market prices for tomatoes is...

Commodity prices are usually expressed in tonnes. It seems at the moment the price is between $70-$80 per tonne. At $70 per tonne, the price would be about $1.2 million. You also need to pay operating costs. If the infrastructure is $200 million, I don't see how they will possibly pay it back. Even at current low interest rates, I don't think you would be able to pay off your loan.

And yes, commodity prices for food are ridiculously low. All of the money goes to distributors. Fix that and we can have nice things like this.

But they aren't selling processing tomatoes for commercial use (pizza sauce, ketchup, etc), they have a contract with a grocery chain for fresh consumer sales. Amazingly enough it sounds like they ran the numbers before spending $200,000,000.

I just figured they had government subsidies. But immediately after posting I decided that the price seemed wrong. There are some references to California producers accepting a contract for that amount, but I have to think it is an error. I can't find a single link for commodity prices of tomatoes.

Maybe as you imply they aren't sold as commodities because the shelf life is too low.

Did they spend $200M of their own money?

I mean, how much of that is government subsidies.

The USDA claims tomatoes cost from $0.92/lb (canned) to $3.29/lb (grape and cherry tomatoes) on average at retail [0]. No idea what retail produce margins are like, but even if we assume they purchase at 10% of retail cost, that's approx $200-740 per tonne revenue to the grower.

If you assume its towards the higher price, and the grower sells at 10% of retail, that's over $1 billion over 10 years (the length of their contract).

[0] http://ers.usda.gov/datafiles/Fruit_and_Vegetable_Prices/Veg...

Generally distributors (including the final shop) take upwards of 80% the final price. Unfortunately I don't have time to get you a better link but just to give you an idea: http://westernfarmpress.com/management/food-dollar-going-whe...

I think they are taking the worst case there, and the amount going to distributors is highly variable depending on the the food itself. If you google around, you should be able to find graphs of various products (probably including tomatoes).

Those are US prices. Australian prices are much higher. And as you cannot store fresh tomatoes, importing them is costly so that prices vary a lot. As said in another comment, they'll sell them at CostCo for A$7 per kilo, which seems to be a competitive price in Australia.

7AUD/kg is 2.41USD/lb.

Fix it? Are there artificial reasons for food prices to mainly go to distributors or are they just the most expensive part? It wouldn't make sense to distort the market to enrich farmers and encourage inefficient ways of growing. When we can't grow enough food on arable land, prices for production will go up themselves and open the door to new technologies.

Nature does a pretty good job of producing food mostly by itself. We may as well take advantage of that where we can before playing in hard mode.

Here in Australia, we trade tomatoes by the kilogram.

They could be a bit more innovative with infrastructure building, like creating glass from the desert sand using solar: https://vimeo.com/25401444 Not sure if it would do clear panes but could be used for pipe work and scaffolding perhaps.

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