## 3 Results and Discussion  
Based on the LCA methodology and the processes described, the results for global warming (GWP), human toxicity-cancer and non-cancer effects (HTP-CE and HTP-nCE), freshwater eutrophication (FEuP), freshwater ecotoxicity (FEeP) and abiotic depletion of elements potential (ADP) impacts are presented in this report. The calculations are based on the available data of each EoL scenario, but, as already mentioned, these processes are not deeply understood, and their inventories are still incomplete. Thus, estimations were made for the missing data based on published experiments and industrial processes. The results presented in this report are not completely representative of the environmental effects of the process and should be used with caution. A summary of all results was calculated using the ReCiPe method, which is recent and harmonises the environmental impacts based on current data [15]. This method's primary objective is to transform all life cycle inventory results, into a limited number of indicator scores. These indicator scores express the relative severity on an environmental impact category and are presented in three categories, i.e., the effect on human health (Figure 3), ecosystems (Figure 4) and resources (Figure 5). This approach is usually beneficial to aid the understanding of environmental outcomes if the target audience is not formed of experts in this field. Figure 3: ReCiPe results (effects on Human Health) in disability-adjusted life year (DALY) for multi- and monocrystalline silicon modules. The comparison of all scenarios studied, presented by the ReCiPe indicators, shows that lower environmental impacts can be achieved through recycling methods. That result is mainly due to the recycling and reuse of part of the raw materials (e.g., silicon and silver) and the glass and aluminium from the frame, which confirms the importance of high-value recycling processes compared to other disposal solutions that cannot reuse or recycle the individual components. It can also be observed that the incineration process produces the worst impacts compared with the other EoL scenarios, mainly because this process uses more primary energy than the other methods presented in this LCA. It is important to highlight that this analysis did not consider any thermal energy or electricity produced by the incineration process, thus no energetic benefit is measured in this scenario. The chemical approach shows low impacts. However, the use of toxic chemicals should always be observed in any environmental analysis. The reuse of the solvent (in this case, toluene) in multiple processes is possible and should be considered, as well as the final treatment when the chemical cannot be used again to recycle new PV modules. Figure 4: ReCiPe results for effects on Ecosystem in species per year (species-year) for multi- and monocrystalline silicon modules. Figure 5: ReCiPe results for effects on Resources in US Dollars (USS) for multi- and monocrystalline silicon modules. From the analysis in Figures 3-5, it can also be observed that reuse seems to be a better option compared to the landfill and the incineration scenarios. In addition, besides reducing impacts, the extra lifetime considered in the reuse scenario also allows more time for recycling technologies to be developed. Besides, the repaired PV modules can be alternatively resold as used panels at a reduced market price of approximately 70% of the original sales price [2], which creates a good opportunity for a significant secondary market for used PV modules. The impacts from the recovery of metals from the bottom ash are significant for freshwater eutrophication and acidification, among other impacts that were not calculated in the present LCA. These impacts are mainly due to the processes of sieving, acid leaching, electrolysis, and acid neutralisation.