Using conventional agriculture techniques to feed the megacities will be massively inefficient in many aspects:
- Inefficient use of water: Globally, agriculture is the largest user of water and highly inefficient!
- Inefficient use of land: in the year 2000 about 37 percent of Earth's land area was agricultural land
- Pollution: Livestock produces around 7.1 gigatonnes CO2-eq. yearly, representing 14.5 % of human-induced emissions
- Inefficient Distribution: the food is produced far away and must be transported which is cost-intensive
The Solution: Aquaponics and Vertical Gardening
Aquaponics is the combination of aquaculture (raising fish) and hydroponics (the soil-less growing of plants) that grows fish and plants together in one integrated system. The fish waste provides a food source for the plants, and the plants naturally filter the water for the fish. Additionally, microbes convert ammonia from the fish waste first into nitrites, and then into nitrates. Which is the form of nitrogen that plants can use to grow. The only water lost in this closed system is the water absorbed by the plants and the water which evaporates in the air, making it the most water efficient food production method!
AND: we can do the whole thing vertically!
When space ran out in the cities, what did we do? We build taller buildings!
Now we need to do the same with our food production. Utilizing the 3rd Dimension will drastically decrease the amount of land we need to produce our food, and also we can now produce the food where it's needed! Plan our food production as part of our megacity or build a big fabric close by? We can even build the whole complex underground and use artificial light to grow our plants. All that gives us the flexibility to produce our food where its needed.
Connecting the Factories:
Furthermore, by connecting and organizing various aquaponics-factories of a megacity together and using trends , sales and order data, we can also produce the right amount of food just in the time it's needed! Reducing the amount of food which will be wasted. This works only because we have eliminated the long travelling time of the product to the market, allowing us to react dynamically to the needs of the customer.
IoT + farming = Aquaponics:
An aquaponic system is essentially a man made ecosystem, which needs to be regulated in order to work. For regulation we will use a whole bunch of sensors, evaluate the measured data in a central server and increase/reduce the concentration of a (chemical) component, if needed.
The most important sensors to ensure the stability of the system are:
- Dissolved Oxygen
- ammonium ion (NH4+)
- nitrate ion (NO3-)
But only producing food is not enough; we need to guarantee the nutritional quality. To do that, we need to ensure acceptable concentrations for the most important nutrient ions. Therefore we need to measure:
Potassium, Phosphorus, Calcium, Magnesium, Sulfur, Iron, Zinc, Copper, Manganese, Boron, Molybdenum, Chlorine, Aluminum, Titanium, Cobalt, Sodium, Vanadium, Lithium
Regulating all these parameters is a challenging task, but definitely doable. Furthermore there are already sensors for the most important ones.
Challenging the world's #1 consumer of fresh water, Aquaponics in combination with vertical gardening has a huge potential for improving the efficiency of megacities and societies around the globe.