"Have you ever wondered how vertical farming compares to other more established farming systems, such as greenhouse horticulture or open-field farming, in terms of carbon emissions? Alongside Tess Blom and Andy van den Dobbelsteen at the Faculty of Architecture and the Built Environment, TU Delft, and Riccardo Pulselli from Università degli Studi di Firenze, we published a paper on exactly this in the context of The Netherlands," shared Andy Jenkins, Co-founder of Urban Input/Output.
Tess Blom, head writer of the research concluded that this carbon footprint assessment illustrates that vertical farms, as they exist today, are not able to provide a sustainable solution to the global issues of decreasing availability of arable land and increasing food demands.
"Even though they do offer great benefits over conventional farming methods. A drastic reduction in energy use to significantly reduce their carbon footprint is therefore needed if vertical farms are to form part of a sustainable, low carbon, and secure future food system."
Comparing growing methods: indoors and outdoors
Using a Life Cycle Assessment (LCA) methodology, the team was able to use data from an operational vertical farm in The Netherlands and compare this with available data on greenhouse horticulture and open-field farming via the KWIN databases, which are made available by Wageningen University & Research.
This data allowed the researchers to understand that the carbon emissions of a vertical farm per kilogram of lettuce produced are much greater than traditional food production systems; resulting in a carbon footprint that is between 5.5 and 6.8 times greater than greenhouse horticulture and 16.7 times greater than open-field farming in The Netherlands.
However, when adjusting for the use of renewable energy, the loss of carbon sequestration as a result of land use change, and homogenous packaging across all farming practices, the rift between these farming systems becomes far less. In fact, these considerations reduce the carbon emissions of vertical farming by 87%, resulting in a carbon footprint that is only 2.3 to 2.4 times greater than greenhouse horticulture and 3.3 times greater than open-field farming when considering the same parameters.
Tess continues, "The results presented are not indicative of all vertical farms, due to the fact that many typologies exist, at different scales, with varying levels of automation and control. However, it presents a baseline understanding of the practice, which allows us to build our knowledge on this subject and push this research to further reduce the carbon emissions of vertical farming."