Environmental life cycle assessment of a large-scale commercial vertical farm

Abstract

Vertical farms are often claimed to have better environmental performance compared to conventional products on the market. However, there are few assessments of the environmental performance of vertical farms, in particular commercial systems. This study has aimed to analyze the environmental performance of a large commercial vertical farm in Sweden producing packaged lettuce. Life cycle assessment was employed to assess the environmental performance and compare it to conventional imported and domestically produced lettuce from a cradle-to-grave perspective. For conventional supply chains, the production, transportation to Sweden, washing, processing, packaging, and final distribution were all included. The results from the study suggest that the vertical farm has lower GHG emissions than conventionally sourced varieties. However, for other impact categories, the vertical farm may have larger environmental impacts from a life cycle perspective due primarily to the large electricity demand. The electricity use, packaging, infrastructure, and distribution of the products to retail were found to be the primary hotspots for the system. Finally, key performance indicators are also provided to compare the results of this study with other indoor farming studies. The results from the KPIs suggest that the vertical farm has better water use efficiency, GHG emissions, and energy use efficiency compared to other studies in the literature. The results of this study provide insights into the environmental performance and resource use of vertical farms, which can be used for comparisons and validation of claims in the industry, and to provide empirical evidence to this developing field.