A newly opened indoor farm in Japan has been built with LEDs
that emit light at wavelengths optimal for plant growth.
It’s the work of plant physiologist Shigeharu Shimamura, who
housed the farm inside a former Sony semiconductor factory. It’s
2,300 square metres, making it the world’s largest LED-illuminated
indoor farm, and is already producing 10,000 heads of lettuce per
The LED lamps allow Shimamura to adjust the day-night cycle for
the planets, allowing them to photosynthesise during the day and
respire at night. Discarded produce is cut from 50 percent of the
harvest on a conventional farm to ten percent, and the lettuces
grow two and a half time faster. Most impressively, stringent
climate control means that water usage is just one percent of the
amount needed by outdoor fields.
The lights were built by GE, which approached Shimamura in 2011 with the
concept. Testing began in 2012, and the final design was laid out
in March 2013. During this process it was necessary to redesign the
lights to be thinner, more uniform and tolerate the humid
conditions inside the factory.
“I knew how to grow good vegetables biologically and I wanted to
integrate that knowledge with hardware to make things happen,”
Shimamura said, adding that similar farms are planned for Hong Kong
and Russia’s Far East. “Finally, we are about to start the real