(July 1, 2015) A Purdue University study shows that
targeting plants with red and blue LEDs provides energy-efficient lighting in
contained environments, a finding that could advance the development of
crop-growth modules for space exploration.
Research led by Cary Mitchell, professor of horticulture,
and then-master's student Lucie Poulet found that leaf lettuce thrived under a
95-to-5 ratio of red and blue light-emitting diodes, or LEDs, placed close to
the plant canopy. The targeted LED lighting used about 90 percent less
electrical power per growing area than traditional lighting and an additional
50 percent less energy than full-coverage LED lighting.
The study suggests that this model could be a valuable
component of controlled-environment agriculture and vertical farming systems in
space and on Earth, Mitchell said.
"Everything on Earth is ultimately driven by sunlight
and photosynthesis," he said. "The question is how we can replicate
that in space. If you have to generate your own light with limited energy
resources, targeted LED lighting is your best option. We're no longer stuck in
the era of high-power lighting and large, hot, fragile lamps."