Its application proved that fresh vegetables can be produced through the efficient use of rooftop in urban areas with much benefit to preventing environmental pollution.

The factory recycles waste from its refectory in an underground methane tank to produce gas, which is to be used for supplying carbonic acid gas into the greenhouse and heating it in winter, and fermented liquid for making organic nutrient solution.

Vermiculite leavening agent and chaff serve as soil for vegetable cultivation in the greenhouse and rainwater is stored for irrigation.

And the temperature control inside the greenhouse depends on solar energy.