More than just food… Part 2

Vertical Farm Produce: More than just food

In part 1, which you can read here, we took a look at the by-products of food production, either of the food directly by way of the parts of the plant that aren’t for consumption or by way of other products that form part of the process toward food production, such as fish in an aquaponics system. We also looked at growing plants not for food but rather for medical purposes. Today we’ll continue looking at what other produce vertical farms can produce.

Algae

Algae is an informal term for a group of photosynthetic organisms, that are polyphyletic in nature, meaning that they are scientifically grouped but don’t necessarily share a common ancestry or biology. The Algae group of organisms ranges from single-celled organisms like Phytoplankton all the way through to multicellular forms, like seaweed. Much like bees and plant byproducts, Algae have a lot of uses.

  • Agar – is a multi-purpose gelatinous substance, that can be used as a laxative, a gelatin alternative, a thickener, but perhaps its most commonly known use is as a culture medium.
  • Alginates, also known as Alginic acid is used in the fields of biotechnology as well as in medical dressings and as a gelling agent in food.
  • Fertilizer – Algae can be very nutrient rich, and as a result, some types of Algae, like seaweed, have been used as fertilizer, as far back as the 16th century.
  • Nutrition – because Algae are so rich in nutrients, they are often used in food, particularly in Asian cultures. Some of the nutritional types include:
    • Vitamin A
    • Vitamin B1
    • Vitamin B2
    • Vitamin B6
    • Vitamin Niacin
    • Vitamin C
    • Iodine
    • Potassium
    • Iron
    • Magnesium
    • Calcium
  • Pollution Control – Algae absorb nutrients from the mediums in which they grow, an ability which can be turned toward controlling pollution. As such, Algae can be used for treating sewage, capturing fertilizer runoff (and the fertilizer filled Algae used as fertilizer themselves), and filtering water sources.

Algae has another use as well, which leads to the next product type.

Biofuels

Biofuels are fuels that are produced through biological processes, in contrast to geological processes, like those involved in the creation of fossil fuels.  Biofuels can be produced from ethanol, which often comes from crops like corn, from biogas, which comes from sources like manure, sewage, and refuse. The other main source is Biodiesels, which are produced from animal fats and plant oils. It’s Biodiesel that can be produced from the oils extracted from Algae.

Biofuels role in a vertical farm could be that given farms sole purpose is to produce a biofuel producing crop, such as ethanol-producing corn, or as a product produced by Algae crops. The reasons for producing Biofuels can be twofold – both as a power-source for the vertical farm and as fuel to be sold. There will be more on power generation later.

Food Waste

I really big problem in the world is a lack of food for the growing population of people, and running out of options for increasing that production. In fact, that is why we are exploring vertical farmings – as a means to grow more food in less space. However, there is another big problem that doesn’t help meeting those food requirements, and that is food waste.

It is estimated that roughly a third of all food produced globally goes to waste, which is approximately a staggering 2.3 billion tonnes. The food that is lost covers a wide range of food type, as seen below:

  • 30% Cereal Foods
  • 20% Dairy Foods
  • 35% Seafoods
  • 45% Fruit & Vegetable Foods
  • 20% Meat Foods
  • 20% Oilseeds & Pulses Foods
  • 45% Roots & Tubers Foods

Imagine how many people could be fed with that amount of food. This waste stems from food lost during transportation, food that is lost in preparation, food that is lost because of expiry dates, and food that is simply thrown away. Some of these issues need to be solved at a legal level, such as the rules surrounding the usage of ‘expired’ foods, and others, such as food loss during transport could be solved by localized production, something you see with vertical farms. Despite any nations best efforts, it is very unlikely that a country could have zero food waste, however, that doesn’t mean that we can’t be better with our food waste.

While there are different ways of managing food waste, one that could be applicable to vertical farms would be the production of Bio-liquid fertilizers made from food waste. With the use of bio-digesting technology, which uses enzymes to break down the food. The main result of this process is a nutrient-rich Bio-liquid which is perfect as a fertilizing agent for plants. Not only could a vertical farm recycle its own food waste, particularly if its lowest floor was a restaurant or supermarket, but it could offer food waste processing to the surrounding city. For a brief look at this technology, watch the video segment below, from 19:25 to 20:50 (timestamp)

Energy Production

One of the predicted issues with large scale vertical farms is energy consumption. Particularly for production arrays that make use of LED lighting, vertical farms become a very energy intensive exercise. In a world where rapid global warming is very much an issue, you don’t want energy-hungry farms using energy that is produced by non-renewable sources. Without viable energy production, vertical farms would very quickly lose their viability as an idea, let alone as a practical implementation. Yet some of the answers have already presented themselves and others are on the horizon.

  • Biofuels and bio-gasses could be a readily available power source. Either as a product of Algae or food waste, the vertical farm could produce renewable energy sources that contribute to the energy consumption of the structure.
  • Solar panels could be built on the roof of a vertical farm, again contributing to the farm’s energy consumption.
  • Solar windows – now while you may have heard of solar panels, you might not have heard of solar windows. The basic principle is that transparent windows have a built-in layer that captures sunlight just like solar panels do. While the technology is a few years away from being efficient, a multi-story vertical farm could have its sunward face be covered with these solar windows, instead of regular windows, again contributing to the overall energy usage.
  • Wind Energy is another option for vertical farms, much like solar panels, they could be built onto the rooftops of these buildings.
  • While not strictly part of the vertical farm, depending on where a farm is built, they could also tap into hydroelectricity from nearby rivers or tidal energy from the ocean.

Depending on the efficiency of the vertical farm and how many energy production mechanisms it has built-in, conceivably vertical farms could not only meet their energy requirements but also exceed them, thus providing renewable energy to the cityscape surrounding them.

P.S.

Interested in today’s topics? Watch the full video above for a look at rooftop farms in Singapore, or check out the links below.

Turning Algae into Biofuel

Global Food Waste Statistics

Solar Windows

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