Life cycle assessment of greenhouse tomatoes for the Swedish market

Abstract

The food supply chain is responsible for a large share of the anthropogenic contribution to global warming, as well as being a major contributor to several other impact categories such as acidification and eutrophication. Therefore, it is necessary to find ways of limiting the impact from food production and the food supply chain. Many crops are not adapted to growing in regions with cold climate, which creates the need to either import them or to use production methods such as greenhouses to artificially create good conditions for the crops. Sweden is currently reliant on imports for many different crops, including tomatoes where most of the consumption is covered by import from the Netherlands. This study uses life cycle assessment to analyze the potential environmental impact of Swedish tomato consumption, by comparing several year-round domestic production scenarios with scenarios representing import from the Netherlands. This is done by using a greenhouse simulation software to simulate a theoretical greenhouse placed in both countries, and then using the simulation results in combination with data from the database EcoInvent to perform a life cycle assessment. The results showed that Swedish domestic production has the potential to decrease the environmental impact of tomatoes consumed in Sweden, when compared to import from the Netherlands. There were a couple of combinations of production scenarios and impact categories where the Dutch production performed better, but the Swedish production scenarios performed better in general. The results also clearly showed that scenarios using LED lighting systems consistently had a lower impact than similar production scenarios using high-pressure sodium lighting systems. The choice of energy sources was identified as a crucial factor when it comes to the environmental impact of the studied systems.