On the way to feed the city!

– Week 3 –

PlantaSymbioSystem

When we look at the trend of the urban population from 1960 to 2014, the urban population had increased 34% and it’s forecasted to increase approximately 5 billion by 2030 (1). The great question is how can we feed more over 5 billion urban population with sustainable and healthy food?

Growing vertically in skyscrapers could be a practical solution that may strengthen issues of food security in modern society.

In the third week, there was a Polish film production team who came to make a documentary film of Plantagon vertical farm in the Linköping City, Sweden. Even though, the Plantagon skyscraper farm is on the way to build in the near future. We had a great chance to see how the vertical plant is going to happen!

So, here is components of PlantaSymbioSystem for Plantagon vertical greenhouse.

Plantagon vertical greenhouse is one growing system in a larger system, since growing plants and vegetables inside the greenhouse need fundamental components that are light, water, air, proper temperature and energy (the important driver of the greenhouse). Plantagon and Swedish cleantech industry have collaborated “PlantaSymbioSystem” which they believe that it could feed the city in the sustainable way (2). PlantaSymbioSystem is a closed loop system which can be divided to two subsystems: greenhouse system and greenhouse supporter system.

Plantagon vertical greenhouse will use high technologies to produce the highest productivity. Due to the climate conditions in Sweden that has a long day in the summer and a very long night in the winter. It’s impossible to use natural light growing plant. Therefore, this Plantagon greenhouse will use artificial lights to grow plants. Moreover, climate environmental agriculture (CEA) will be used in this greenhouse as well such as evaporation collectors, dehumidifiers, ventilation controller and heating/cooling system. Hence, they don’t have to depend on fluctuated climates and light. That’s why a vertical greenhouse can produce crops locally all year round. The technical details of the Plantagon vertical greenhouse will be explained later in the next week after I interviewed Joakim, the technical manager of Plantagon International AB.

The most crucial part, which is a main driver of the Plantagon vertical greenhouse, is “energy”. The energy component is generated from the greenhouse supporter system. As can be seen in Figure 1, energy will be generated from renewable energy plants such as bioenergy, wind and/or solar power as primary sources. Then, it will be converted to electricity and heating/cooling systems to use in the greenhouse. The Plantagon vertical greenhouse will be located between the Linköping Biogas plants (Figure 2). Both biogas power plants will provide heat and electricity to utilize in the greenhouse. Furthermore, plant residuals from the greenhouse can be used as biogas materials (3).

The Linköping City can produce total energy from renewable sources such as biogas. We had a chance to interview Stafan Jakobsson – Head of Department, Business Development, The Linköping Biogas plants how waste can turn into bioenergy. He explained that all waste is separated to landfills, reuse, material recycling and organic waste. Organic waste is delivered to a biogas power plant and generated to biogas and biofertilizer. The residual left over after reuse and recycling in the waste procedure are sent to the combined heat and power plant to generate heat and electricity. Electricity power is sold to Nord Pool Spot which is the leader of power market in Europe. Some part of heat from the combined heat and power plant and other producers is distributed to households and commercial buildings.

References:

(1) http://www.citymayors.com/statistics/urban-population-intro.html

(2) http://plantagon.com/urban-agriculture/industrial-symbiosis

(3) http://www.tekniskaverken.se/om-oss/in-english/waste-to-energy/