Plant Factories Blossom Production in Japan steadily flowers Eiichi Ono and Hiroyuki Watanabe
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America developed an automated spacing device for growing-area optimization and used water-cooled lamps for removing excess heat from the high-intensity-discharge (HID) lamps. However, such projects have failed commercially. Geniponics was purchased by Control Data Corp. in 1980 and then shut down in 1984. Classification Phytofarms of A plant factory can America was closed be categorized in one in the early 1990s. of two major facility In contrast, curtypes based on the folrent plant production lowing facility characfacilities across the teristics: the degree of Pacific Ocean have closure and the levels been successful thus of natural-lighting far. In Japan, a numusage. The first facility ber of plant factories type is the semi-closed have opened since system, which has limthe late 1980s and ited environmental are still operational. control capabilities. Such projects Such a system often include Secom Herb harnesses natural light Factory (Secom for the purpose of High-Plant Co., reducing lighting costs. Ltd.), which proThe other is a closed duces a variety of facility, which utilizes herbs; TS Farm (Q.P. PASONA O2, an underground facility, showcases current plant production technologies. artificial lighting under Above: a room Corporation), which for tomato production. a highly controlled utilizes aeroponic environment for increased productivity. system, and systems from La Planta Co., LTD., which uses fluorescent lamps for crop production. In addition, most Factory failures and successes of these plant factories are even adding franchised faciliA number of closed-type plant factories have been ties. In 2000, Cosmo Plant Co. LTD. introduced a lightconstructed in the United States since the 1970s decade. emitting-diode- (LED-) based plant factory, Cosmo Farm, Examples include GE’s Geniponics, located in New York which is the world’s first commercially operational LEDand Alaska, and General Mills’ Phytofarms of America up based plant factory. The Cosmo’s system utilizes highand running in Illinois. These U.S. plant factories have intensity red LED, which is the most inexpensive among made highly interesting attempts at plant production. For different colors, for producing lettuce crops. The daily example, Geniponics produced tomatoes and sold them for production capacity of some of Cosmo’s plant factories are higher prices than most other companies. Phytofarms of up to 7,000 heads of lettuce. he concept of a plant factory, which produces crops under a controlled and optimized environment, has been pursued since the 1970s. Potential advantages of such a facility are high productivity, year-round continuous production, pesticide-free harvests, lower water demand, and effective land use.
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Interestingly, these plant factories have made different selections for artificial lighting in their facilities. For example, some factories utilize fluorescent lamps (La Planta), while others utilize high pressure sodium lamps (TS Farm), and LED-lighting systems (Cosmo Farm).
LED lighting systems
Among these lighting technologies, the LED lighting system has created the most interest. The advantages of using a LED lighting system are space savings, lower energy cost, longer life expectancy, and flexibility in controlling light quality as well as quantity. Recently of note … While the cost is the most important limiting factor Another engaging project has emerged in Tokyo: for a LED-based plant factory, there are some other PASONA O2. Though issues. For example, the facility is not currently only limited intended for commerPASONA O2 is an underground facility numbers of crops have cial crop production, been grown under the facility highlights with six growing rooms … Each room LED-lighted environcurrent crop production ments. The majority of showcases different concepts and technology. Since its the current commercial inception in 2005, it plant factory facilities technologies. In the facility, different focus on producing has gained much media attention, and the prime vegetables. types of lighting devices, such as LEDs, leafy minister of Japan has However, vegetable visited the facility. such as strawberlaser diodes, cool white fluorescent fruits, PASONA O2 is an ries and tomatoes, have underground facility the attention of lamps, metal halid lamps, and high- gained with six growing producers. Greater rooms, with a room for knowledge is needed pressured sodium lamps are used. rice field, tomatoes, for determining which herbs, vegetables, letplants can be grown tuce, and filed flowers. Each room showcases different conunder LEDs and what combination of light quality would cepts and technologies. In the facility, different types of be the most beneficial. lighting devices, such as LEDs, laser diodes, cool white fluAnother issue for the LED lighting system is the coolorescent lamps, metal halid lamps, and high-pressured ing problem. Elevated temperatures in a LED lighting syssodium lamps are used. tem causes lower efficiency and also lowers the life expectancy of the LEDs. Therefore, developing an efficient cooling system is needed. An encouraging trend has been observed: the output from LEDs commercially available is increasing while the cost of LEDs is decreasing. This trend should boost the feasibility of LED-based plant factories in the near future. Some believe that the emergence of plant factories in Japan is due to unique circumstances: land shortage, low food sufficiency ratio, high population of quality-conscious customers, and high labor cost. However, the concept and technologies developed for Japanese plant factories would be useful in many other countries. R ASABE member Eiichi Ono is a research fellow in the Applied Life Science Research Center at Tamagawa University Research Institute, 6-1-1 Tamagawagakuen, Machida-shi, Tokyo 194-8610 Japan, eiichi@alumni.engr.arizona.edu. Hiroyuki Watanabe is co-developer of Cosmo’s LED-based system and associate professor in the Faculty of Agriculture, Department of Life Science at Tamagawa University, 6-1-1 Tamagawagakuen, Machida-shi, Tokyo194-8610 Japan, watahiro@agr.tamagawa.ac.jp. PASONA O2 exhibits the application of laser diodes for plant production.
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Resource March 2005 2006