Design of a Modified Shipping Container as Modular Unit for the Minimally Structured Modular Vertical Farm

摘要

The specific aim of this study was to advance the development of the Minimally Structured & Modular Vertical Farm (MSM-VF), an original concept developed at The University of Arizona, by designing a specific modular unit made of a transparent-walled modified standard shipping container for use in climate locations represented by Los Angeles and New York City. The conclusions of the study included: (1) A workable range of temperatures (15 to 30°C) for cultivating tomato in Los Angeles and New York City could be achieved in a transparent-walled MSM-VF shipping-container modular unit by using a cover material of low density polyethylene (LDPE) and a heating, ventilating and air conditioning (HVAC) system with an airspeed of 2 m/s, inlet angle at 60° and outlet position located at the top of the back wall; (2) A workable range of temperatures (15 to 27°C) for cultivating lettuce in Los Angeles and New York City could be achieved by using a cover material of LDPE and an HVAC system with an air speed of 4m/s, inlet angle at 60° and outlet position located at the bottom of the back wall; (3) The annual energy demands of the plastic-walled MSM-VF shipping-container modular unit were far less than those for the opaque-walled control plant-factory unit in all cases, except in the one case of growing tomato in New York City. Still, in this one exception, the annual energy demand of growing tomato in New York City in the plastic-walled MSM-VF shipping-container modular unit of 557.65 kWh/m² (versus 325.34 kWh/m² for the opaque-walled control plant-factory unit) was significantly lower than that of 711.91 kWh/m², which was the average for 164 greenhouses occupying a total of 16444 m² operated by the Cornell University Agricultural Experiment Station (CUAES) in the state of New York (CUAES Greenhouses); and, (4) The annual energy demands of the plastic-walled MSM-VF shipping-container modular unit were either significantly lower or for one case approximately the same (773.84 kWh/m²) as that of the 711.91 kWh/m² for the New York greenhouses. By contrast, the annual energy demands of the opaque-walled control plant-factory unit significantly exceeded that of the 711.91 kWh/m² for the New York greenhouses by 170% for Los Angeles and by 126% for New York City, both for growing lettuce. The foregoing results provided significant and reasonable basis for the practicability of Minimally Structured & Modular Vertical Farms made of plastic-walled shipping-container modular units in Los Angeles and New York City as well as in many other mega-cities around the world with similar climates.