## 2 Literature Review  
Trends in Charging Infrastructure Development of Private and Public Passenger Transport at the Regional Level  
There are a number of charging stations of different types that have been installed in the last decade in European Union, ranging from a few kW to 475 kW. Several incentives for the installation of charging infrastructure, both public and private, for electric vehicles have been introduced and are being assessed as to their effectiveness [15]. In the EU, countries such as the Netherlands, France, Germany, and Italy show the highest numbers (as shown in Figure 1), and there has been continuous and rapid growth in recent years.  
This is supported by the forthcoming revision of the Alternative Fuels Infrastructure Directive [5], which aims at introducing binding targets for electric vehicle charging points in EU27, with the current regulation recommending that there should be at least 1 charging point per 10 cars [4]. Despite the growing need for charging stations corresponding to the growing electric vehicle numbers, access to public charging stations is limited compared to conventional fueling stations. Another current trend is the uneven geographical distribution of charging stations for EVs. In Italy, for example, 57% of those are located in the North, while 23% are in the Central, only 20% are in the South and the Islands, and 34% are in the regional capitals [16].  
Technologically, the trends for the new types of charging stations consist of increasing the power transmitted and vehicle-to-grid (V2G), enabling them to be able to provide axillary services, and improving power quality for the distribution system operators [17]. Inductive power transfer, which is one of the wireless energy transfers, is seen as another trend within charging systems for EVs that would allow potentially extending an EV's battery charge in dynamic charging [18]. Mobile charging stations is another technological possibility that is being introduced to equip areas with weaker grid connections or those were such connections are absent [19].  
For electric buses, one trend is the development of the network of conductive charging technologies (pantographs or charging through the plug), which is considered to be more  
Figure 1: Charging infrastructure in EU27 for electric vehicles. Source: EAFO, 2022 [1].  
mature, with the possibility to transfer up to 600 kW [13; 20]. Another charging technology for buses involves providing less power at a higher infrastructural cost; this is an inductive technology, which has a lower visual impact compared to pantographs. Dynamic wireless charging technology was shown to be more cost-effective with larger bus fleet sizes than small fleets [21]. There are significantly growing numbers of electrically chargeable buses in Europe (+78.7% in 2021) and a market share of 10.6% [22], which will require the development of adequate infrastructure at the regional level considering geographical, extra-urban, and urban constraints, as well as the clarification of the responsibilities for the development of such infrastructure and research on new business models.  
Another innovative concept in electric vehicle charging infrastructure for e-buses is the shared infrastructure with other operators. This has been implemented via a second external charging point, which is not in conflict with the first charging point dedicated to the bus service only. Bus charging has priority, so if a bus passes by and charges for some minutes, in this time frame, the secondary charging is paused [23].