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Vertical Farming Does not Save Space

If the electricity for a vertical farm is supplied by solar panels, the energy production takes up at least as much space as the vertical farm saves.

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Urban agriculture in vertical, indoor “farms” is on the rise. Electric lights allow the crops to be grown in layers above each other year-round. Proponents argue that growers can save a lot of agricultural land in this way. Additional advantages are that less energy is needed to transport food (most people live in a city) and that less water and pesticides are required.

Which crops?

The vertical farms that have been commercially active for several years all focus on the same crops. These are agricultural products with a high water content, such as lettuce, tomatoes, cucumbers, peppers, and herbs. However, these are not crops that can feed a city. They contain hardly any carbohydrates, proteins, or fats. To feed a city, it takes grains, legumes, root crops, and oil crops. These are now grown globally on 16 million square kilometers of farmland - almost the size of South America. 1

Growing wheat vertically

An art installation currently presented in Brussels - The Farm - explores what it would take to grow wheat in a vertical farm. For the experiment, 1 square meter of wheat was sown in a completely artificial environment. By measuring the input of raw materials such as energy and water, the project shows the extent to which natural ecosystems support our food production. When wheat is planted in the ground next to each other, instead of above, the sun provides free energy and the clouds free water.

A loaf of bread for 345 euros

The experiment shows that growing 1m2 of wheat in an artificial environment costs 2,577 kilowatt-hours of electricity and 394 liters of water per year. The energy required for the hardware production (such as lighting) is not included in these results, so this is an underestimate. The building’s energy cost is also not taken into account, and that concerns both the construction and its use, for example, for heating, cooling and pumping water.

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The cost calculation does include the price of the equipment (1,227 euros). The lifespan of the infrastructure is estimated at 8 years. Converted, the production of 1 m2 of wheat in an artificial environment costs 610 euros per square meter per year (including infrastructure, electricity, and water). Of this, 412 euros goes to electricity consumption and only 1 euro to water consumption. This calculation may be an overestimate because the installation is set up in an exhibition space.

The “farm” produces four harvests per year. With every harvest, enough wheat is grown to make one loaf of bread (580 grams), which has a cost of at least 345 euros. Each loaf contains 2,000 kilocalories, the amount that an average person needs per day. As a result, 91 m2 of artificially produced wheat is necessary for each person, with a total cost of 125,680 euros per year.

The paradox of vertical farming

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. 2 In that case, there’s not much sustainable about it.

Calculated at a yield of 175 kilowatt-hours per square meter of solar panel per year, the indoor cultivation of 1 m2 of wheat requires 20 m2 of solar panels. This is a underestimate because the calculations are based on the average yield of a solar panel. There is much less sunlight in winter than in summer. In reality, the vertical farm requires many more solar panels to keep operating all year round. There is also a need for an energy storage infrastructure, which costs money and energy too. Finally, solar panels’ production also requires energy, which would demand even more space if the production process itself were to run on solar panels.


All this criticism also applies to vertical farms where lettuce and tomatoes are grown. In this case, there is a significant reduction in water use. These companies are profitable, but only because the process relies on a supply of cheap fossil fuels. If solar panels supplied the energy, the extra costs and space for the energy supply would again cancel out the savings in terms of space and costs. The only advantage of a vertical farm would then be the shorter transport distances. Still, we could just as well make transport between town and countryside more sustainable.

The problem with agriculture is not that it happens in the countryside. The problem is that it relies heavily on fossil fuels. The vertical farm is not the solution since it replaces, once again, the free and renewable energy from the sun with expensive technology that is dependent on fossil fuels (LED lamps + computers + concrete buildings + solar panels). Our lifestyle is becoming less and less sustainable, increasingly dependent on raw materials, infrastructure, machines, and fossil energy. Unfortunately, this also applies to almost all technology that we nowadays label sustainable.

Kris De Decker

More info: Solar Share (The Farm), by (Maria Roszkowska, Nicolas Maigret) and Baruch Gottlieb.

Proofreading: Eric Wagner


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You are ignoring nuclear energy, in which case a vertical farm is both space saving and sustainable.

kris de decker

Conference paper that argues along the same lines:

How sustainable is the smart farm?

Rob Lee

Wow I didn’t know solar panels were the only way to produce electricity for vertical farming! I sure am stumped at finding out what other methods exist to produce electricity that doesn’t involve on-site power production through solar panels. I hope someone invents something soon.


This oversimplifies the issue a bit, but most of the energy in the solar system is nuclear energy, unless I seriously misunderstand stars.

I’ve never understood the big problem with earth based reactors. Sure nuclear disasters are bad news, but when you put them up against all the other industrial pollutants that get leached into environments from petrochemicals, I’m way more willing to take the risk.

If we had spent the last 30 years using our technological prowess to build safer and better traditional reactors, the world would be a much better place.


It looks like a static analysis ignoring the fact that solar power efficiency is increasing every year.

If those companies are already profitable now by innovating, they will be ready to scale when we will need them the most.


This criticism relies upon the false dichotomy of power coming from either solar or fossil fuels. Wind, tidal, or even nuclear avoids that issue. Furthermore even if powered with solar panels those panels do not need to be placed on fertile farmland, so there need not be a substitution.

Pertaining to the selection of crops, vertical farming does not need to grow every crop to be valuable. Farmland currently growing tomatoes or cucumbers could be switched to growing grains as those fruits are grown in vertical farms. Vertical farming would allow growing more grains and legumes on cropland currently devoted to cucumbers and peppers, significantly increasing the amount of land available for staple crops even if staple crops cannot currently be grown in vertical farms.

Distance is not the only consideration in transportation. Bulk goods like grains are not as perishable as cucumbers - logistics becomes much simpler when costly refrigeration and rapid transport is no longer a significant concern. If delicate perishables are grown in cities while only shelf-stable bulk goods are shipped in then the savings goes far beyond simple distance.

On a more speculative note, I would not expect staple crops to ever be grown in cities even in vertical farms. If bulk food production needs to be shifted into urban areas it would likely be in the use of large bioreactors for nutrient production while crops in vertical farms will still only be high-value fruits and herbs.

Brian Horakh

Wheat has a horrible photosynthetic utilization rate compared to other crops, it is only comercially viable with free energy. Potatoes can be grown indoors successfully.


People don’t seem te be aware that nuclear energy is much more expensive then fossil and solar.


Once the initial capital costs paid they will be amortized out over thousands of cycles. The costs that mater are the inputs of power and mineral.

Hydroponics excels at leafy greens. I have grown lettuces in a tower using led grow lights, 10 gallon mixing tubs, blue dow insulation, netpots, master blend, CaCO3, and epsom salt, grow plugs and net pots. (If I followed BA Kratky’s method with even less). The output in leafy greens has paid for itself in less than a year when comparing it to Aldi’s lettuce.

The reason why we continue to grow greens this way is because of pest pressure and the limited growing season. It allows us a continual supply of nutrients not calories. Microgreens are also economical to grow this way. I am considering making something akin to the FarmTek fodder system 3.0 (They have an excellent manual.) which only requires water and heat (solar, compost, animal BTU) To convert barley into a more effective feed.

I don’t think that wheat is a good representation of vertical farms. It is an interesting experiment all the same. But the costing and longevity is poorly calculated.

Ginny Newsom

The author does not take into account areas where the growing season is very short, land is not arable and so may be put to better use with solar panels etc. The article is basically a jumping off point to compare net productivity gain with the least energy inputs. Otherwise … what’s really the point?


this is insanely stupid.

Nobody thought that vertical farming would save space INCLUDING the energy infrastructure. But if you want to make a lot of food on the north pole, HOW ELSE DO YOU DO IT.

Meaning, vertical farming is already choosing a tradeoff. You are criticizing the tradeoff without even realizing it, thus coming off as insanely stupid.

Thomas M Idzikowski

What an incredibly stupid “hit"piece. Do more research before embarrassing yourselves.


Solar panels could be on rooftops, or at sea or lakes/reservoirs.

And where land is used, what kind of land? Solar can be put on barren and desert land, leaving fertile soils to revert to forest/prarie, etc.

Plus of course there’s wind, nuclear, geothermal.

And vertical farming isn’t just about land size, but also efficiency, transport, freshness, and so on.


Gaia, since Italy is very densely populated place, it takes more people to adjust to your wishes and at least to me considering other options is only logical. If I need a solution to something, I prefer to do something that gets result and as soon as possible. Taking hostages and making demands or throwing tantrums also is an long lasting option, and it all depends on when you’d rather have those few people around.

As for wheat growing indoors - since wheat price on Mars costs more, than on North Pole, it suddenly makes sense to grow wheat in indoor condition. Vertical/indoor farming is not really limited only to Earth or growing on land - it could be as well applied to grow food on ship or sea platform or even under the sea(sunlight can still reach plants to some depth). If it is something that you don’t want to use and instead want to stick to more traditional ways, it is your choice to do so, but you have no say if someone else will see this technology as an opportunity to them and will use that technology. Simple.

As a dweller of North, I definitely see decent life where I can grow anything - including tropical fruits. It sure will make joy in achieving this goal and fun(and not sustainability) is most important part of life. I also think, that it is better to grow exotic fruits locally, than spend fuel by transporting and keeping those fruits refrigerated from other side of the globe. I sure do want to have naturally grown bananas, that are not soaked in chemicals so they can endure that travel.

My ancestors were so sustainable, that they burned some part of crops after the harvest or drowned 50% of valuables, they plundered. The way I see it - sustainability has nothing to do with nature or past of how those starving farmers lived and it is very modern thing - clearly to force others how to live and even how to think. Traditional ways are most damaging to nature and indoor farming is sure more ecologically friendly than current farming methods that involves use of pesticides.

When you are selling something on market, both buyer and seller are happy about a deal, because each of them are gaining something that is more valuable to them than to other person. There are no trade-offs and both parties are winners. To some pain is something they need - it could have been figure of speech, but I was just slightly curious if that was something that is your preference in trade.

James Simpson

This is a thoughtful and provocative article which has male, pro-capitalist, technophile readers fuming with rage. Obviously, solar is not the only technology which is classed as renewable to supply vertical farming. But every energy source is dirty in different respects and fossil fuels had the huge advantage of being more energy-dense than pretty much all alternatives. Why else did our 19th-century ancestors abandon wind power in favour of coal and then oil?

Solar farms might not take up land currently used for growing humans’ food but it is used for other purposes, including habitats for other forms of life which are largely excluded from it. This technology relies on extractive, polluting industrial systems, if not so much as any fossil fuel, and is not really sustainable.

Gaia Baracetti

Foldi-One, though it makes sense to try and grow some food near sources of natural light in existing buildings, the higher the building, the longer of a shadow it casts. So, whatever you gain in terms of light, you take it from the surroundings; you either reduce the natural light falling on nearby land, damaging agriculture or natural ecosystems, or you reduce the natural light falling on other buildings, so that THEY will then need artificial light for people who live or work in them.

Not to mention that building vertical greenhouses would require enormous amounts of energy, materials and maintenance, whereas agricultural land is already there. There are places that have to import even sand for construction having run out of their own (causing erosion, ecosystem destruction, etc).

There are no miracles, only finite sources going around.

David Bourguignon

Dear Chris, thanks for yet another thought-provoking piece. We need more debate in general, informed by science to move together forward towards a desirable future. And artists can help ask relevant questions.

To me, vertical farms are a bit like electric cars: there is something inherently strange at trying to change the “core engine” without changing also the “form factor” (ie. mass/speed/shape/etc. which is related to energy service/efficiency/etc.)

As pointed out by current cars are only 1%-energy efficient, therefore producing EVs with the same “form factor”, as heavy and matter/energy intensive as cars, make little sense from a sustainability point of view. This is the first iteration, and this will inevitably change very quickly, given the harsh constraints we will be facing soon.

IMHO we should see the current attempts at designing vertical farms the same way: they try to keep afloat, in front of a changing climate, the 10,000-year old agriculture/food system, based on cereals and cattle (in many parts of the world), while in fact its “form factor” is no longer right for the time we live in.

According to many authors such as fighting climate change and biodiversity loss will require ecosystem restoration and rewilding on a large scale, that is turning current cropland back to primary biomes (eg. forest, prairies). This will require in return that we start growing new kinds of food from micro-organisms in an entirely new way.

In comparison with the vertical wheat farm your just described, check the environmental impacts of for an example of what could be around the corner.

All the best.

Gaia Baracetti

Yanis, that’s why you should always put human population density into the equation. Of course certain ways of life only work (but work very well) when there aren’t too many people.

I’d rather have fewer people moving herds over a vast landscape than cram people so much that they need to rely on intensive animal farming and problematic (as this article shows) agricultural techniques like we do in most of Europe. I don’t think you can innovate your way out of the overpopulation problem without damaging the environment in some way. Overgrazing or not, with its low population density the area inhabited by the Saapmi is still much better in terms of wilderness than the Netherlands.

I am Italian, I live in the Alps, and would say the same about us both ways, I only mention the Netherlands because you did.

(And no, we don’t need to kill people to reduce the population, low fertility can do that for us much less painfully)


Vertical and indoor farming will feed cities when people accept surviving on algae and fungi.

Jose Amador Silva

One of the many issues to note here is the lack of multi calculations for the product being grown.

Case in point: Most of the lighting and hence, energy requirements can be eliminated if one used vertical growing for mushroom production in cities. Old, abandoned skyscrapers could be reasonably retrofitted to do this and minimal light needed. This would also reduce the distance to farm for the nutrient stream to return to the farm.

A second case is new construction that takes advantage of natural solar light for growing, and raising the ceilings of each growing floor. Instead of a square building stacked up high, imagine a thinner rectangular structure with a larger base (which might be used as a seed starter for the higher floors). Most of the floor space could get sufficient light to grow and orientation could supply adequate solar heating. Water is recycled in the building, minimizing the need for additional rainwater and minimizing runoff into rivers.

Older buildings, which can’t be retrofitted easily, can be used to create multilevel aquaculture facilities. These do not need much light as well, and floors could be used to grow insects for feeding the fish directly from city waste.

Light well buildings can also be created using a stacked donut method of skyscraper construction. Smaller thinner donuts at the top. Trees lining the bottom layers. Vines for grapes and cucumbers high up on the edges.


Gaia Baracetti, you are quite correct there are ’no miracles, only finite sources’… Doesn’t mean we can’t be more efficient in how we build and use the sources. The tips of many skyscrapers are thin and under utilised anyway - and being thin and tall can capture sunlight to grow crops while not casting anything else much in shadow - the shadows move rather far in a short time.

Also most of these tall buildings need to pump lots of water to the top anyway for sufficient water pressure so its not new hardware, if you can recycle the grey water from the upper floors for the plants as well -probably not worth pumping it from the bottom floors that high…

Agricultural land is never going to go away with this population level, but again that should be better managed - we don’t need massive mono-cultures of crops over vast areas, or to be pumping the centuries of slow filling groundwater dry watering cattle.

There is no one ‘fix’ that does everything, but properly done many little tweaks to our lifestyles can make a massive overall change. And vertical farming is certainly a better use of energy and water than the Burj Khalifa’s very impressive water fountains in the middle of a damn dessert…


It’s incredible seeing everyone up in arms over the simple fact that we will never be more efficient than what nature provides. Any attempt to bypass this is going to create a gap somewhere. How many people in these comments are farmers or gardeners? Or actively work in nature? Do you know anything about the reality of how things functions or just an abstract ideal that you’re pulling from? I can spend a couple hours prepping a space, plant some seeds, and with that, I have a secure source of food for months. Because I choose the right plants, I do not water, fertilize, or provide anything other than occasional pest management with my hands. If I were to grow mustard greens in my house, the amount of energy I would put into it versus getting out, I would always run a deficit. You cannot avoid that. If it’s not a deficit in energy to power lights, it will a deficit in energy from gather materials to pot it, to water it, to provide amendments, etc. Not to mention, you cannot pull out a chunk of soil and expect to provide nutrients for ever. The earth builds fertility, when disconnected, it atrophies. Simply put, you cannot ‘beat the system’. So when you ask stupid questions like “How do we feed a large number of people in the North Pole?” Maybe a better question is, why are we inhabiting spaces that require us to attempt to bend nature to our will, just waiting for it to snap back and destroy the fragile supply chains society relies upon. The amount of people upset over this article just goes to show how entrenched we are as a world where we have to continue living how we have been within the last century and deviation of that spells the end of mankind.


It’s said, that there were 2,577 kWh per year used.

2577 kWh / 365 d / 24 h = 0.294 kW = 294 W of constant power.

That seems a lot for 1 sq meter. Even if you use not the best technology, should be about half of that. But even cutting power in half or even 4 times does not change the main idea, that such endeavour is hardly sustainable. This explains why locally grown cucumber costs three times more than imported from warmer climate.

Michał Kolbusz

Most commentators focus on the technical side of vertical farms, completely ignoring the economic side. For a technology to catch on, it is not enough that it is technically possible, it must also be economically viable. If it is not, it will most likely be out compete by a cheaper alternative. The Farm’s calculations show that even if electricity and water were free, one loaf of bread would cost around 120 euros - 100 more than from traditional farming.

This happened with many technologies that were to change the face of the world, and due to their high cost, they only inhabit modest niches: 3D printers, cargo drones, ultrasonic passenger planes, flying cars, nuclear energy, corn ethanol, bio diesel, are all mature technologies with decades long research put into them. They have been try many times to scale up but stopped at some point due to high cost. This is true with nuclear energy which stopped growing few years after Chernobyl and in “stasis” since then ( High cost of nuclear power plants makes them affordable only for rich countries.

Same thing applies to much simpler and more common technologies. Lets take for example asphalt roads. When price of oil hit historic high between 2008-2016 (above 100 dollars) many counties in USA started to turn asphalt roads into gravel roads because they couldn’t affords oil derived asphalt - few hundreds of thousand miles where turn into gravel. High oil prices didn’t make bitumen roads technologically impossible, just made them economically nonviable.

Same thing is true with vertical farming. It can’t compete with traditional farming (organic, primitive, high-tech) which is why we still eat bread that comes from the “countryside”.

In this article Kris points at very crucial problem with indoor farming, shared with most today “sustainable” technologies. If the technology is dependent on non-renewable resources it will continue to exist until they are exhausted. Because they eventually will be exhausted, technology has limited shelf life. This is true with most high-tech technologies and even ten coats of green paint will not hide it.


LOL @ all the tech-bro types getting all offended at this article.

Let’s do some simple math:

  • Crop land covers 15 million km^2 on Earth.

  • Sunlight, averaged throughout the day & night, contains 200 watts per square meter. (peak = 1000 watts per square meter)

Therefore, to recreate that much light in vertical farms, we need at least 3 million gigawatts.

That’s over 1000 times the world’s electricity consumption!

You really think you have a way to generate that much power in the near future? Nice try.

“But thats a strawman bro! I never said we have to replace ALL farming with vertical farms!”

Ok fine, try replacing 0.1% of farming with vertical farms - you’ll STILL need the entire world’s power grid.


What about windows combined with solar panels ?

Emily Rasmussen

Most vertical indoor farming concentrates on short growth time, fresh to market produce.

While wheat is not practical for this technology, other produce can be.

Farming wheat uses large machines. It does not seem that the cost of these was calculated.

It is cheaper to transport electricity for long distances than farmers produce.

Large hydro power plant would be more economical than solar cell farm.

Since vertical farming is indoors, it would be fairer to compare it to greenhouses.

There is less damage to produce during shipping if distances are shorter. Meaning less waste.


  1. Smil, Vaclav. “It’ll be harder than we thought to get the carbon out [Blueprints for a Miracle].” IEEE Spectrum 55.6 (2018): 72-75. ↩︎

  2. Atomic power and wind turbines are other options. See the comments. ↩︎