Plant factories in the water-food-energy Nexus era: a systematic bibliographical review

In recent years, several global issues related to food waste, increasing CO2 emissions, water pollution, over-fertilization, deforestation, loss of arable land, food security, and energy storage have emerged. Climate change urgently needs to be addressed from an ecological and social perspective. Implementing new indoor urban vertical farming (IUVF) operations is one way to combat the above-mentioned issues as well as foodborne illnesses, scarcity of drinking water, and more crop failure due to infection from plant pathogens and insect pests. A promising production mode is plant factories (PFs), which are indoor plant production systems completely isolated from outside environment. This paper mainly focuses on the comprehensive review of scientific papers in order to analyse the different applications of urban farming (UF) based on three different dimensions: a) the manufacturing techniques and equipment used; b) the energy that these systems require, the distribution of energy, and ways to minimize the energy-related cost; and c) the technological innovations applied in order to optimize the cultivation possibilities of IUVF.