Kinkajou : Do you have any other concerns about the viability of vertical farming?
Erasmus :Absolutely yes. I think many people are designing or dreaming about vertical farms , and are only concerned with the building or construction process . In the long-term, vertical farms must economically compete with existing farm production outputs and costs. The concept could very easily come to grief on problems that no one is even mentioning.
People talk about multistorey buildings becoming vertical farms. However, let’s just look at the economics of an existing condominium or multiunit building. Getting access to such a building requires an elevator. Servicing and maintaining an elevator could easily cost somewhere in the region of $30-$50,000 per year. If the condo is what we call a six pack in Australia, (a building with six separate habitation units), the cost of the elevator must be shared amongst the six units. This gives a cost of $5000 to $8000 per year per unit.
This is paid as body corporate fees levied on each unit within the building. This adds a lot to the expense of living in such a unit. For a vertical farm, the farm has to generate this much money to break even on costs. So cost of access to your farm layers/ stories becomes a cost issue. For a vertical farm, this could easily be a make or break issue.
A similar issue is the mixing of multistorey buildings made of concrete or concrete steel composites, with the presence of free water. Water can penetrate concrete and is significantly accelerate rusting of steel reinforcing. In Australia we call this “concrete cancer”. Your wet building used for farming will literally fall apart, as the steel corrodes, rusts and expands.
Most multistorey buildings can guarantee longevity because they keep water away from the steel. This will not happen in a vertical farm, as plants need to be watered and water leaks will invariably occur. Water will invariably penetrate past paint barriers. However for most condominiums all six-pack units, simple painting is quite adequate to minimise corrosion and enhance building longevity. Vertical farms will require much more serious efforts to waterproof them to protect their structure.
Vertical City Urban Farm
So our building construction codes, are currently not adequate to the needs of vertical farming. If you have to you replace your vertical farm every 30 years as it rusts and falls apart, the whole vertical farming concept becomes unviable.
There is another issue with building construction codes. Building vertical farms will require a huge culture shift for how we build our cities. Vertical farms need light and natural light must be maintained as much as possible to reduce maintenance costs. So a typical vertical farm, may only be able to be 5 m wide and may require a height of 3 to 4 m per story, in contrast to most residential buildings requiring a height of 2.4 m per story in Australia. You cannot just use a normal residential building as a vertical farm.
Vertical farms can be built on the tops of tall city buildings. However, to provide a commercially viable space may require an additional 8 to 10 stories on the tops of said buildings, used for farming only. Farms need to be oriented to maximise light access. This means it is likely that the farm orientation may differ from the orientation of the building underneath it. This means building design must be modified to allow the weight of the upper stories to be carried on the structure below. Farms will also need a specific critical separation to maximise light. (They cannot be too close to each other.)
Kinkajou : So summarise your thoughts about building vertical farms.
Erasmus : Currently we are not doing it.
We are not “urban planning” to do it. We have no experience with vertical farming in urban areas. We do not have the commercial model for profitable farm usage. We do not possess the technologies for efficiently generating the right sort of light. The energy we use is too expensive.
City Urban Farming
It looks like vertical farms need to be long and thin. But we can’t afford to have an elevator to a tiny little farm, even a multistorey vertical farm on every building. We may have to share one elevator in a multi-story vertical farm which spans a number of urban buildings. This means there could be saying six buildings forming the base of a single vertical farm. We just don’t build them that way, because every skyscraper owner builds their building as unique structure, not designed to interface with the buildings adjacent or next door to it.
We do not have a cropping model. (That is, what crops in what rotation over what time in what space add up to a productive enterprise)? Our crops may need to be genetically modified to improve yields in this sort of the growth environment.
Our energy inputs are unlikely to make this type of farming economic at this time. Fossil fuel power sources are likely to be too expensive.
In short we have a long long long way to go.
Kinkajou : Enough of the bad things. Tell us about some of the advantages of vertical farms.
Erasmus : Vertical farms would create a seismic shift in how we produce our food.
Environmentalists alone should be trying to further this idea with every ounce of effort they have. The vast Quantities of pesticides and herbicides would no longer be required, instantly eliminating agricultural pesticide and herbicide runoff.
Caterpillar
Kinkajou : Rubbish. As I see it vertical farms only make it difficult for crawling insects to proliferate. If a city is full of urban farms flying insects would have no difficulty at all in spreading from building to building. So we will still be using pesticides. We could perhaps limit the spread of flying insects by a enclosing a vertical farm with glass. However this will reduce light entry (float glass is actually a faint blue or green colour), may increase the cost of climate control, and generates maintenance costs in terms of cleaning.
What we are also likely to face is a proliferation of insects that use humans as a vector. Why waste time and energy getting to your pasture when humans can carry there.
Erasmus :Well okay. The next advantage would be that Soil erosion wouldn’t be an issue anymore, not to mention deforestation.
Kinkajou : Yes but many of our current plants are perhaps not able to thrive in a hydroponic environment. More time and effort needs to be spent in developing strain suitable for this type of growth environment.
Insects affect Farms Good and Bad
Erasmus : The traditional “supply chain” would be completely removed along with all of the fossil fuels burned and money spent in the process. No longer would your wheat get shipped in from Australia and your corn from America to you in Europe. Rather all your vegetables, fruit and even some things like chicken (think any small animal) would be grown only a short distance from your front door. It gives a new meaning to the words farm fresh and farmers’ market.
For pretentious eaters such as myself I’d have some of the freshest produce I’ve ever consumed. The vegetables are grown and within hours could be available for sale after harvesting on my local stores shelves or at the farm market.
Kinkajou : Again most of the energy in food production is not in the transporting of foodstuffs. In a vertical farm most of the energy requirement will reside in the need to supplement available light.
Erasmus : Notice we still have a professional production model here for the vertical farm. I have heard some idiots suggest that people can wander outside, pluck their fruit and vegetables and eat them on the spot. You need to have people with skills to produce food skillfully. This means they need to earn money to enable their work to be sustainable. If someone does something you need to pay them to keep doing it.
Kinkajou : Yes I can see is unlikely that vertical farms based in cities will have city dwellers ambling around harvesting food at random. It’s hard to believe that anybody could seriously propose such a thing. Some of these idiots probably deserve a Darwin award for even thinking that such a process could be viable.
Backyard HYDROPONIC SETUP
Erasmus : From a more economical point of view the list of pros continues unabated.
Costs of distribution? Gone.
Produce spoiling during transport? Gone.
One huge plus is the ability of farms to produce crops year ‘round. Climate “mitigation” delivers expanded growth seasons and cropping.
Kinkajou : I haven’t heard the concept climate mitigation before. Tell me more.
Erasmus : I am not advocating” climate control”. It is probably more economically viable to produce a good growing environment for plants with a few energy inputs, than a perfect growing environment for plants with extensive control of temperature humidity and other environmental factors requiring a much higher energy input. Hence the word “mitigation”. The weather, or season, is likely to still be important in vertical farming. Despite the numerous benefits, the costs of tailoring the temperature, humidity, lighting, and airflow 24/7 is extremely expensive. So these factors need to be mitigated to improve plant growth, but at minimised cost.
Kinkajou : what about the energy?
Erasmus : Renewable energy, of which solar is the leading candidate, bypasses this issue, or would if it weren’t for the cost of installing these systems. I don’t personally think this will be an issue for long due to the exponential nature of technology. Eventually, and it is eventually, the price of the systems will drop while their effectiveness and efficiency will increase. As soon as this happens we’ll hopefully start seeing mainstream acceptance of vertical farming.
Then we may see something quite interesting. Solar voltaic panels collect solar light energy across a range of frequencies. This electrical energy is then converted by LEDs into a narrow range of light frequencies able to be utilised by chlorophyll. A clean green, light and food making machine, our vertical farm.
Plant Light Bulbs
Erasmus :In any case, never forget supply and demand. More people need more food. Even if it costs more, you still need to eat. You have to get your food from somewhere. The reality is that broadacre farming will not continue to deliver the gains in food production that we require. Changes in food production must continue to allow the burgeoning human population to survive.
Kinkajou : Having to feed all those people really does worry me.
Erasmus : Yes. I understand your concern about the impact of huge populations. I have been hearing about a theory whereby civilisations grow to a point to where they must inevitably collapse. Civilisation is a process of increasing optimisations and increasing efficiencies. These are essential since as the population grows, more food, water, power and shelter must be produced to sustain them.
Inevitably a point is reached where the system is optimally efficient. Then a failure in some critical subsystem causes a chain of collapse in interlinked systems, bringing about a catastrophic collapse in the entire civilisation. Billions starve and die. Civilisation could rebuild itself at this point, but if you add war and conflict into the equation, there may not be a lot of upside for recovery for hundreds of years.
Terrace Farming Asia East
Kinkajou : You’re a worry wart, Erasmus. You know that.
Erasmus : Someone needs to worry about us all. And that includes those species on the planet that are at the mercy of humanity. As population increases the demands on our planet increase as well. Humanity in seeking to sustain itself, is denying this opportunity to almost every other species on the planet.
Kinkajou : I’ll add something else to your doomsday scenario. If what that doctor says about Paill Spectrum is correct, improved health would easily translate into improved longevity. If people lived longer the population would explode and resource requirements (Food, power, shelter) would increase exponentially. That just the sort of situation that would set up the basic conditions for a catastrophic collapse.
Erasmus : Yeah! I forget about the implications of the Paill Spectrum model. The way it looks it’s too close to call whether the human race calls Dr Xxxxx a saint or just burns the dumb bastard on a stake.
Kinkajou : The Paill Spectrum doctor is an Innovator true. But sadly sometimes our greatest successes can at the same time form our greatest failures. The future awaits.
Kinkajou : So what have you learnt, Goo?
Goo : Vertical farming is something that just has to happen. However, there are other choices. If humans can learn to extract glucose from plant feedstocks, (composed of cellulose, hemicellulose and lignocellulose materials), the average farm could increase its usable or harvestable energy production by a factor of 10-20. That’s probably enough to increase the number of people on the planet by a factor of ten to twenty. Imagine a world of 70- 140 Billion people. An awesome place!
There are a large number of changes and technologies required before this dream can become reality. Legislative changes for building codes to allow farms to span multiple high rises, to make buildings water resistant and to allow altered property rights and usage access rights are a long way from allowing this reality.
Technologies such as photosynthetic light generating LEDs could completely revolutionise the process of growing food.
I think the Pham Nuwen acclamation that civilisation is a process of increasing optimisation and adjustment of circumstances to requirements that continues until a point is reached when the failure of a single critical subsystem could trigger the collapse of an entire world , is frightening. Even if humanity could build and feed a world of 140 Billion, should it? The acclamation is only relevant when the pressure of the needs of population subsistence causes excess demands on a system. If a system always has a layer of “fat” or a reserve, such critical events can most likely be avoided.
Vertical Stacking of Starter Plants