Vertical farming: Skyscraper sustainability?

It is predicted that the world population will reach 9 billion by 2050, of which 70% will live in urban centres. This change, alongside a changing climate, will strain Earth's resources, especially the food supply chain. One idea that has been proposed to address this issue is vertical farming - the urban farming of fruits, vegetables, and grains, inside a building in a city or urban centre, in which floors are designed to accommodate certain crops. While an interesting theoretical concept, no studies currently exist that quantify or qualify the validity of such an idea. The purpose of this paper, therefore, is to examine the feasibility and plausibility of the vertical farming concept from a socio technical, mixed methods, research perspective. This includes (1) examining how much energy is needed to power such a building and whether renewable energy can meet the onsite demands of the building by constructing a energy model, (2) quantifying the carbon footprint of vertically grown produce and subsequently comparing that to conventionally grown produce, and (3) conducting interviews to explore how relevant stakeholders perceive the concept of vertical farming in order to identify what are current barriers and opportunities exist towards possible uptake of the technology. The findings indicate that vertical farming is a tool that can be used to supply food to cities in a sustainable manner, but this depends on the location and design. Areas of future research are identified. (C) 2015 Elsevier Ltd. All rights reserved.