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the absence of oxygen that also yields pyrolytic gas and bio-oil as co-products . While these co-products
[22]
can be utilized as energy source to make the pyrolysis plant self-sufficient, biochar application to agricultural
soils offers the dual benefit of long-term carbon sequestration and agronomic improvements . Some studies
[11]
have already explored the benefits of applying biochar to olive groves as a strategy for improving soil
fertility [17,23] , and promoting a circular economy within the olive industry [15,24] . Similarly, extensive research in
other agricultural systems confirms biochar’s role in enhancing soil structure, increasing organic matter
content, and retaining water and nutrients [8,11,25-27] . This evidence makes a wide-scale implementation of
biochar particularly attractive, as it offers a pathway to valorize local residue streams while simultaneously
addressing land use challenges and contributing to climate change mitigation and adaptation.

Andalusia’s high solar irradiance (1,240-1,847 kWh m year ) has driven a rapid expansion of
-1 [28]
-2
ground-mounted photovoltaic (PV) parks, with regions like Sevilla leading Spanish PV installations
(5,904 ha) . This trend is creating direct competition for arable land, with olive groves identified as one of
[29]
the crops most displaced by permanent PV installations . AVS emerges as a strategic solution to
[29]
accommodate multiple land uses, offering a pathway to sustainable land management and mitigating the
conflict between agricultural and energy sectors . This approach has already been explored for olive groves,
[9]
with studies assessing its technical feasibility and optimal configuration [30-32] . The 2-axis tracking AVS
technology typically stands out due to its better cost-revenue ratio and environmental performance
compared to traditional fixed systems . Beyond resolving the land-use conflict, AVS also provides direct
[33]
agronomic co-benefits, as PV panels are reported to increase soil moisture and water retention by providing
shade, which in turn reduces soil temperature and contrasts desertification trends [9,10,34-36] . This potential is
now backed by national policy, with new governmental incentives that aim to promote renewable energy
transition while ensuring compatibility with agricultural activity , with funds already allocated to 13 new
[37]
AVS projects in Andalusia .
[38]
Despite the growing interest in biochar and agrivoltaics as strategies to enhance the long-term sustainability
and resilience of olive production in Andalusia, there is a lack of comprehensive, life-cycle-based studies
quantifying their integrated potential and environmental performances, as well as analyses that assess
pathways for their practical combination. Current research largely treats biochar and AVS as standalone
solutions, without considering their combined application within the region’s specific biophysical and
resource constraints. Consequently, the potential synergies, trade-offs, and overall environmental
performance of jointly deploying these technologies in Mediterranean olive groves remain unknown. This
knowledge gap limits our understanding of how such integrated approaches could contribute to climate
mitigation, sustainable resource management, and farm resilience, and hinders the development of
evidence-based policies and incentives to support their large-scale adoption.

In this work, we address this knowledge gap by conducting a life-cycle assessment (LCA) of integrating
biochar and agrivoltaics in the olive groves of Andalusia, Spain, following a regional-level approach. To
define the scope and spatial extent of these interventions, we first quantified the regional availability of
biomass residues within the olive oil industry, followed by a site-specific analysis to identify areas with high
risk of soil erosion to prioritize biochar application, along with areas with high agricultural intensity as most
suitable for AVS deployment. Five distinct scenarios are then developed to evaluate the environmental
performance of different deployment scales at the regional level. The analysis estimates the potential
renewable energy generation, affected land area, and a range of environmental impact indicators to assess
potential co-benefits and trade-offs. Renewable energy is generated from both cogeneration of pyrolysis
co-products combustion and the deployment of 2-axis tracking AVS technology. The environmental benefits
from the generated electricity are quantified only for the additional surplus produced relative to the baseline,
and they are assessed against a dynamic Spanish power mix that reflects progressive decarbonization. The