ENERGY AND ECONOMIC CHALLENGES OF VERTICAL FARMING IN EXTREME CLIMATES: A FEASIBILITY STUDY

In high-latitude countries, the fresh vegetable supply chain is both costly and challenging to maintain, relying on refrigerated trucks, reefers, or even more expensive air transportation. The cold climate and the low solar irradiance in these regions make it difficult to farm crops in traditional greenhouses. In this context, investigating the impact of on-site food production system is valuable. To meet the necessary growing conditions, such as temperature and light levels, a controlled-environment vertical farm (CEA) utilising artificial light boost crop yield could be developed. This study simulated and analysed four different growing condition scenarios, each coupled with two distinct free cooling strategies, from both energy and economic perspectives. The cold external climate allows for the use of free cooling strategy to reduce energy consumption. With indoor conditions set at 24°C and 200 µmol m-2s-1, the direct free cooling system proved to be the most energy-efficient, with a specific electric demand of 5.28 kWh kg-1. From an economic standpoint, however, the most productive scenario, coupled with the indirect use of external air for free cooling, turned out to be the most cost-effective, achieving a cost of lettuce of 5.23 € kg-1