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compensated for the displacement of grid electricity, resulting in a net reduction of 6% for scenarios S4 and
S5. Nonetheless, the high uncertainty observed and the overlap between the scenarios prevent drawing
robust conclusions in this category.

Freshwater Eutrophication (FEP) in the reference system is dominated by phosphorus emissions from the
manufacturing of glyphosate in herbicides (45%), followed by irrigation (26%), and fertilizers (25%). In
Scenario S5, the impacts from irrigation and fertilizers are both reduced by 4%. Although AVS
manufacturing introduces a new industrial burden of 0.78 kt P-eq·year , this impact is effectively outweighed
-1
by the benefits from renewable electricity generation, resulting in a total net reduction of 51% ± 32%.

Fine Particulate Matter Formation (PMFP) follows a similar trend to TAP. In the baseline, 54% of the impact
stems from ammonia and NO emissions associated with fertilizers. While this driver is reduced in biochar
x
scenarios, as fertilizer consumption is reduced, it is outweighed by emissions from the energy intensive
manufacturing of silicon for PV panels. However, the credits from electricity substitution compensate for
these AVS burdens, resulting in a net reduction of 25% ± 25% in S2, and up to 49% ± 23% in S5, compared to
the baseline. However, the uncertainty ranges of scenarios S2 and S3 overlap.

Carcinogenic Human Toxicity (CTUh) is principally driven by irrigation in the baseline (72%). The largest
benefits are here achieved with S5 (70% ± 7.87%), due to the biochar increased water retention and AVS
reduction in irrigation needs. While AVS systems introduce new burdens, they are completely compensated
by the energy generation credits.

Terrestrial Ecotoxicity (TETP) presents a different profile. In the baseline, the impact is 10.21 Mt
1.4-DCB-eq year , dominated by emissions associated with the manufacturing and application of
-1
agrochemicals, specifically fertilizers and herbicides. However, when AVS is introduced, PV panel
manufacturing becomes the dominant contributor due to the emissions of heavy metals and intensive energy
use required for silicon and component production. In this case, electricity substitution is insufficient to
compensate for the total impact, with S4 showing the largest relative increase (74% ± 60%) compared to the
baseline.

This analysis highlights that synthetic fertilizer production is the dominant driver for many impacts
categories, including TAP, MEP, PMFP and TETP. Consequently, management strategies that reduce
fertilizer dependence demonstrate a clear pathway to mitigating these critical on-farm impacts, a problem
already highlighted from other assessment studies in olive groves . Biochar contributions to increase soil
[71]
nutrient retention help to mitigate this environmental hotspot. Results also clearly show that the
interventions proposed introduce environmental trade-offs stemming from AVS manufacturing, most
notably in TETP and FEP. While these burdens are currently compensated by electricity credits in most
categories, this contribution will gradually decrease as the grid decarbonizes. This underlines the importance
of reducing the embodied impact of the agrivoltaic system, which has been observed to be highly sensitive to
panel efficiency and technological advancements.

Site-specific implications
Figure 7 summarizes additional implications of the evaluated scenarios at the hectare scale, providing
farm-level insights that are not fully captured by the regional aggregated results shown above. To facilitate
this comparison, the results focus on the specific technologies, namely biochar, AVS, and their combined
application (biochar + AVS), when applied to a single hectare, allowing for a direct evaluation of the
management system's impact on a per-hectare basis relative to conventional land management (baseline).
Absolute values are provided in Supplementary Table 23.