Life-cycle environmental analysis of combined biochar and agrivoltaic systems in Andalusian olive groves

Abstract

Agricultural activities in Spain are increasingly vulnerable to water scarcity and soil degradation, exacerbated by farming intensification and climate change. Alongside, the need for renewable energy generation expansion and negative emission technologies risk increasing land use conflicts. Sustainable strategies to reconcile measures to improve agricultural resilience with the renewable energy transition should be explored. This study evaluates the life-cycle environmental performance of integrating biochar production from residues from the local olive oil value chain with agrivoltaic systems in Andalusian olive groves. Five scenarios consider various constraints for regional biomass availability and for agrivoltaic deployment. A spatial analysis identifies the olive groves that are most suitable for agrivoltaic installation and prioritizes high-erosion groves for biochar application. Integrating these technologies delivers climate change mitigation, in some cases achieving net negative emissions and reducing global warming potential by up to 173% relative to conventional farming. Biochar-induced soil carbon storage transforms the agroecosystem from a net source of emissions (2.14 t CO₂-eq ha^-1) to a carbon sink (-7.90 t CO₂-eq ha^-1), while reducing soil erosion and improving water retention. Agrivoltaic systems further decrease irrigation demand and provide up to 53 TWh of renewable energy. Trade-offs occur with terrestrial ecotoxicity and freshwater eutrophication, but using more advanced and efficient panels can mitigate these burdens. Overall, the combined implementation of biochar and agrivoltaics can co-deliver across multiple environmental challenges, from local valorization of residue streams to enhanced agroecosystem resilience, climate change mitigation, adaptation, and renewable energy generation.

Keywords

Life cycle assessment / carbon sequestration / climate mitigation / sustainable agriculture / solar power / soil erosion / energy transition

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