식물공장은 지속가능한 대안인가?

(Is Plant Factory a Sustainable Alternative?)

This study examined whether the plant factory is a sustainable alternative in Korea s agriculture. We conducted the economic as well as environmental analysis. The results show that the production cost of plant factory lettuce is 14,432won per kg, which is about 14 times higher than the production cost of greenhouse lettuce (1,060won/kg). From the environmental perspective, energy inputs and CO2 emissions from a domestic plant factory were 63 and 58 times higher than those of greenhouse vegetable, respectively. In order to produce 1kg of plant factory lettuce, 309MJ energy that correspond to 8.7 liters of gasoline are needed, while emitting 14.6kg of CO2. According to the analysis on plant factories in Japan, although they are relatively small scale facilities, the economy of scale is not found. Moreover, the difference in yield per unit area between the old and latest facilities is not significant, and the yield per unit area seems to diminish as the cultivation area increases. It looks difficult to expect a significant increase in productivity from larger sizes or technical advances. The main reason behind the large consumption of energy and emission of CO2 is that the photosynthesis is performed with artificial light. The plant factories show a poor productivity increase compared to the input of artificial energy.