## 4 Results and Discussion
### PV Panels LCA
Transportation was considered under the assumption that the distance from the PV plant to the nearest collection point of electronic waste is no more than 100 km, and the distance between the collection point and the recycling site is 400 km. The novel process of recycling has a sequence of physical (mechanical and thermal) treatments, followed by acid leaching and electrolysis. The amounts of energy produced by the incineration process (for example, the incineration of the sandwich layer and plastics from cables) are considered as coproducts and their positive impact calculated as a credit (avoided environmental impact). By contrast, the environmental credits derived for potentially substituted primary materials are not included. The modeling and calculation were implemented with SimaPro software version 8.0. The ILCD midpoint method was used for the life cycle impact assessment (Table 2). The \"mineral, fossil, and renewable resource depletion\" impact category is replaced with \"abiotic depletion, fossil\" and \"cumulative energy demand (CED)\" in order to distinguish the contributions of energy sources from those of nonenergy materials. The \"land use\" and \"water resource depletion\" impact categories were not taken into consideration due to their high uncertainty. The results of this study do not have direct applications for the eco-design of the power system. However, they can be used to calculate the entire life cycle of c-Si PV modules for any method of installing panels and for any location. [PERSON] [11] extended the results obtained in [72] by introducing options for the recycling process that depend on the material of the back-sheet. This study also introduced several additional impact categories. The results indicated that there is little potential to reduce the environmental impact of the recycling process in some categories due to the variation of materials for the back-sheet and recycling technologies for the auxiliary parts of the PV panel. [PERSON] and [PERSON] [73] considered both individual stages and the entire life cycle of thin-film CdTe modules. They used two different functional units: 1 m\({}^{2}\) of the module and 1 kWh of energy produced. An interesting feature of the study is the comparison of impacts of the module with and without the balance of systems (BoS). It was revealed that the relative contribution of the BoS on the total impact of the PV power plant is around 35% to 45%. Estimates of environmental impacts for 1 kWh of electricity as a functional unit are made under three different assumptions about the amount of solar radiation in the location of the solar power plant. The disadvantage of the study is the lack of accounting for the effects of transporting new modules to the installation site and used modules to the recycling site. As shown above, transportation can have a significant influence on all environmental impact assessments. In addition, in this paper, the lifetime of the PV modules is assumed to be 30 years, which is an overestimation. The authors of [74] presented a rather unusual approach to life cycle analysis, which the authors defined as \"grave-to-cradle\". They suggested that recycled silicon should replace a virgin material in the production of PV panels and considered the process in terms of industrial symbiosis. Recycling is carried out using thermal and chemical methods. [PERSON] and coauthors [75] investigated two c-Si PV panel recycling scenarios: one with a high level of material recovery and another with a low level. Environmental impacts were calculated in two versions: including credits and excluding them. The disadvantage of this study is the lack of accounting for transportation. Comparing the environmental impacts of recycling with the impacts of all previous stages of the life cycle presented in EcolInvent (Tables 3 and 4), one can conclude that any technology for recycling PV waste is more ecologically friendly than landfilling.