Growing Food for Space and Earth: NASA’s Contributions to Vertical Farming

Perhaps one of the first demonstrations of vertical farming was carried out by NASA with the Biomass Production Chamber at Kennedy Space Center, FL.  Plants were grown on four circular shaped shelves stacked vertically in a closed chamber, with lighting provided with 96, 400-W high pressure sodium lamps.  All the plants were grown using a recirculating nutrient film technique, and transpired humidity was condensed and returned to the hydroponic systems.  Crops tested included wheat, soybean, potato, lettuce, tomato, rice and radish.  This allowed validation of basic protocols developed by university researchers but on a larger scale, and inside a tightly closed atmosphere.  The closed atmosphere allowed tracking of volatile organic compounds produced in the system, including ethylene gas, which was chemically scrubbed for some tests.  Subsequent testing using standard growth chambers expanded to include LEDs as a light source, and a demonstration of a roof-top solar collection system with optical fibers delivering the light to a chamber inside the building.   A series of plant growth tests was also carried out in NASA’s Habitat Demonstration Unit for planetary surface missions.  In this case, the plant growth system was placed on a circular shelf surrounding a lift between the lower lab module and the upper crew quarters module.  This took advantage of under-utilized volume for growing food within a human living space.  More recent testing has focused on testing and selection of dwarf cultivars to maximize production per unit volume for space missions.  Many of these concepts and technologies being studied for space align closely with challenges for terrestrial vertical agriculture.