Rethinking Efficiency: How Increased Electricity Use Can Reduce Environmental Impacts in Controlled Hemp Cultivation—A Life Cycle Assessment (LCA) Study

This study aims to assess the environmental profile and identify environmental hotspots of indoor hemp (Cannabis sativa L.) cultivation through environmental impact analysis under four scenarios combining two nutrient solutions and two lighting intensities (540 W and 900 W). Indoor cultivation of industrial hemp is becoming increasingly relevant as plant production shifts to controlled environments, raising the need to evaluate its environmental implications. The assessment was conducted using the Life Cycle Assessment (LCA) methodology in accordance with the ISO 14040 and ISO 14044 standards, applying a cradle-to-gate system boundary and a functional unit of 1 kg of dried hemp inflorescence. Primary data were obtained from a controlled cultivation experiment, while secondary data were drawn from validated databases. The carbon footprint ranged from 1050 to 1610 kg CO2 eq per kilogram of dried inflorescence. Scenarios with 900 W lighting showed 30–35% lower impacts per kilogram compared to 540 W variants. Electricity production and consumption were identified as major environmental hotspots, dominating most impact categories. The study concludes that improving input–output efficiency is essential for sustainable indoor cultivation and that integrating renewable energy sources, such as photovoltaics or biomass, could further reduce environmental impacts.