The Science of Vertical Farming: Why Farm Vertically?
Why farm vertically?
Even in comparatively open landscapes with large areas of agricultural land, such as South Australia, there are benefits to this style of farming. Despommier lists these advantages as:
- Year-round crop production with no weather-related crop failures, eg. floods, drought
- No use of herbicides, or fertilizers and within a closed, controlled system possibly pesticides as well
- Use of 70-95 percent less water
- Less agricultural runoff
- Transport of food and consequently carbon footprints are reduced significantly
- In a closed system, more control of food safety and security
- New employment opportunities
- A constant supply of animal feed made from post-harvest plant material
Vertical farms can also produce more than two dimensional farms because; crops can be grown 24 hours a day, year round; 1 indoor acre can be equivalent to 4-6 outdoor acres, or more, depending on the crop; and in closed systems crop failure due to the impacts of pests, diseases and weather (droughts and floods) can be greatly reduced.
In some respects vertical farming might be viewed as a fancy innovation; nice but not necessary, particularly if the costs of establishing a farm are considered. But along with agricultural production, vertical farms can:
- convert waste water to drinking water
- convert methane gas to energy, and
- free existing farmland to be returned to natural systems.
The positive impact of reducing fuel use and carbon emissions through eliminating the need for transport, including tractors and ploughs, is also a significant benefit.
Downsides include construction that is potentially high in initial material and energy supply and high ongoing power consumption due to artificial lighting, particularly where it is used round the clock. However, with careful design and enforced standards farms could be built out of unused and available building structures with reliance on renewable energy (wind or solar) from the outset.
To us in Australia it may seem foreign to need urban-based agriculture when viable and productive land is nearby. But with ongoing population growth, space will not always be an option and we must be knowledgeable about alternative agricultural practices. With innovative concepts such as vertical farming, which bring together the best of our knowledge from many fields of science, perhaps urban-based farming could follow behind the plough, Haber-Bosch process, drip irrigation, herbicides and pesticides as the keys to the latest agricultural revolution.
By Heidi Alleway