## 2 Method
### E-Road  
The present study analysed the impact of a motorway that has been upgraded to include DWPT technology. The e-road design and the WPT layout are the result of a joint effort of different partners from the European project \"feasibility analysis and development of on-road charging solutions for future electric vehicles (FABRIC)\" [35]. The design of the e-road depends on the application it is intended for. E-roads lend themselves to many applications, including private transport, freight trucks and public transport. Buses were among the first pilots to use WPT [11; 36]. The application of inductive charging to urban buses results in several advantages, including fixed routes [37], the easily obtainable standardisation of the vehicles and the involvement of municipalities [34]. The fixed route and the time spent at stations while loading and unloading passengers are exploited to have enough charge to cover the whole bus route [37]. The particular nature of this type of transport allows buses to mainly be recharged using WPT systems and the buses to be provided with a buffer battery [37]. The transition to WPT for private transport is more complex, but the potential CO\({}_{2}\) savings are relevant [10]. This type of infrastructure will first be deployed along high-density motorways. The introduction of WPT to motorways will act as a range extender for electric vehicles going from one city to another, thus allowing time savings to be achieved, since the recharging occurs while the vehicle is in motion. The scenarios developed by FABRIC considered the trans-European transport network (TEN-T) infrastructure as a first deployment, where the DWPT infrastructure have dedicated 25 km long lanes (in both directions) for the dynamic charging of light and heavy electric-vehicles along the most crowded motorways between two locations approximately 400 to 600 km apart. The lane is not reserved for WPT vehicles. The layout of a suitable e-road for such a scenario was developed as part of a collaboration between the partners of the FABRIC project. The WPT solution was developed by POLITO. POLITO developed the charge while driving (CWD) solution, which is based on the dynamic wireless resonant inductive coupling principle [38]. The details on the layout are presented in [38; 39; 40; 41]. Hereafter, a simple, brief description is given to help understand the system and the subsequent LCI. The primary coils collect power from a low-voltage, three-phase, connection point and the road-side control system converts the AC voltage to DC and then to a 600 V 100 kHz rectangular waveform in order to transfer the power, through the air gap, to a secondary coil. The POLITO solution at the test site consists of 2 branches of 25 coils individually fed by DC/HF converters. Each coil has a DC/HF converter and the distribution is at 600 V DC. The feeder can be connected in parallel to the same cable (see Figure 2). In addition, a super capacitor solution is provided to balance the possible load variations. The power electronics can operate at any frequency over the 20-200 kHz range, although it is essential that the primary and secondary circuits operate at the same frequency. The CWD system operates as a constant secondary current, which means that the power control can be done at the secondary side without any additional controller. This means that it is also easier to transfer power back to the network. However, no power will be sent back to the grid in the developed solution. The power transfer rate is 20 kW. The secondary voltage will be able to span from 0 to 400 V, that is, for a full rate power transfer from 300 to 400 V. The primary input voltage will be 600-700 V DC. The current solutions are connected to three-phase 400 V AC substation feeder points. However, the current solutions are primarily experimental and are mainly used in controlled environments, where the installation is only used by a small number of vehicles.