## 3 Results
### Calculation of \(CO_{2}\) Emissions

Table 3: Summary of the main direct and indirect impacts due to the high use of EVs for V2G or G2V mode. For NC and WCNC modes, items relating to telecommunication and data processing infrastructures are excluded. studies) on the different possible impacts, and thus know the emissions estimated in them. Taking into account that the different studies identified presented results from different perspectives and focuses, it was necessary to convert and standardize the quantities and units in order to calculate a final value that could be compared with the emissions of an ICV (whose CO2 emissions already are extensively studied, as they have been on the market for a long time). For the emissions calculation process, it was necessary to define base values for the calculation. To this end, values and data relating to the EU (EU average values) or values from EU countries were sought. Respecting the developed framework, to calculate the emissions (from a macro perspective) that result from the use of EVs on a large scale, the following partial sub-calculations were defined:  
1. Calculation of emissions resulting from the life cycle of an EV (from cradle to grave): 1. Extraction of resources and their processing and transport; 2. EV manufacturing (including battery); 3. Electricity consumption for charging during use (including losses in the charging system); 4. Disposal and eventual recycling after end of life (EV and battery). 2. Calculation of emissions due to the installation and operation of large-scale telecommunications, control, automation, processing, and data storage infrastructures. 3. Calculation of emissions due to the installation of new infrastructure and operation of the electricity distribution network. Since most of the available data relate to light vehicles, this study was limited to this group. Smaller vehicles have fewer emissions considering life cycle analysis, regardless of whether they are electric or not. EVs have fewer emissions (over the entire life cycle) than an ICV if we use the EU electrical energy mix, but this does not happen for all vehicle ranges. Therefore, the value calculated in this study is an average value, which applies to mid-range vehicles. 1. Calculation of emissions resulting from the life cycle of an EV. To calculate the emissions associated with a given technology, it is necessary to use an appropriate methodology, such as life cycle analysis. This is the methodology that was used in the identified studies [25]. This methodology takes into account the emissions resulting from the processes of extraction, processing and transport of the necessary resources, the entire process and energy required for manufacturing, the energy required to use the vehicle in its circulation phase, and emissions from the production phase and recycling or disposal after end of life [29]. This methodology is quite complete and comprehensive, obtaining results that are good indicators of emissions associated with the life cycle [26]. However, in the case of EVs, disposal/recycling is a step that is not yet well known and studied because EVs are a recent technology, with no infrastructure or organized recycling/disposal system [23]. For this reason, it is not yet reliable to calculate the emissions associated with this stage of the EV life cycle, so any calculation of emissions will likely be an estimate below the real values because they believe it will be possible to recycle EVs. Circulation/use is the longest phase of an EV's life cycle and therefore it is very important to calculate the emissions associated with it. However, it is not always simple to calculate these emissions, because emissions during EV use depend greatly on the mix of electricity production used to charge the EV. If electricity from production using coal (for example) is used to fuel EVs, they will have more emissions than non-electric vehicles [30]. But if only wind production is used, an EV emits about 10% of the emissions of an ICV during circulation. In the present study, data on the EU's electricity production mix were used.