Modeling production and energy needs of a vertical farm

Vertical farming represents a promising practice in the agricultural field with clear advantages in water savings and no need for pesticides, but it generally requires a relevant amount of energy in terms of lighting and internal conditioning. For this reason, the trade-off between yield and energy consumption needs to be evaluated. In order to do so, in this study, a transient model capable of evaluating both energy consumption and plant production as a function of internal temperature and light intensity was developed. Plant growth is a function of internal environment parameters as well as energy consumption. In the model both these two aspects were accounted for: building physics behavior (0D model including wall inertia and resistance thermal bridges and external ambient conditions in terms of air temperature, humidity and solar irradiation), conditioning plant (air treatment unit and internal heating/cooling units) and plant growth as a function of internal conditions. The model was realized in Simcenter AMESim, a multiphysics software allowing the development of 0D and 1D models of various physical systems. Results showed the production capacity of the vertical farm for two sizes of buildings and for various combinations of internal temperatures and light intensity, thus energy consumption. The study is performed for Boston (USA), representative of a humid continental climate, densely populated town with a high cost of life.