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Crops on the Moon and Mars: An Energy-Saving Approach to Optimizing Biomass Production Using Novel LED Lighting Strategies. G. D. Massa1, J. C. Emmerich2, R. C. Morrow2, C. M. Bourget2, and C. A. Mitchell1 1Purdue University, West Lafayette, IN, 2 Orbitec, Madison, WI.

   The NASA Specialized Center of research and training in Advanced Life Support (ALS NSCORT) has been charged by NASA to reduce equivalent systems mass (ESM) for advanced life-support systems ten-fold by 2010.  Using a combination of interdisciplinary research and bioregenerative approaches, we are exploring technologies that will efficiently support humans for long duration missions.  The primary goal of the crops focus area is to reduce the ESM of crop growth by significantly lowering the energy necessary for electric lighting of crops. 

   A collaboration has been formed between the crops focus area of the ALS NSCORT and the Orbital Technologies Corporation (Orbitec).  Together we have developed a reconfigurable LED plant-growth- lighting system designed to reduce energy requirements by targeting the light only to where photosynthesis is occurring.  In the intracanopy configuration, the LED light engines hang vertically within the crop canopy of planophile species and can be switched on incrementally as plants increase in height, thereby eliminating mutual shading of leaves, which occurs in overhead--lighted canopies.  Preliminary tests indicate an increased harvest index relative to plants grown beneath overhead lights.  In a close-canopy configuration, the light strips can be arranged as a horizontal plate and brought in close proximity to rosette or erectophile crops.  In future hardware generations, automated switching technologies currently under development will allow discrete switching of each light engine as plant tissue grows beneath or parallel to it.  Automatic plant detection is being tested under a phase 1 SBIR awarded to Orbitec, and HELIAC, or “high efficiency lighting with integrated adaptive control”, has been successfully tested on several ALS crop species.  A whole-canopy gas-exchange cuvette is being constructed to measure real-time crop-stand responses to LED lighting protocols and to optimize those protocols for ALS crops.