# A Literature Review on the Charging Behaviour of Private Electric Vehicles
## 2 Literature Review and Method
### Analysis of Users' Preferences and Needs
#### 2.2.1 Survey-Based Papers
Data from travel surveys are combined with those from the charging of an EV fleet to evaluate the impact of charging on the grid [35; 36]. Other survey-based studies explicitly focus on investigating users' charging preferences and which factors affect these decisions. A joint study based on stated mobility and charging choices [37] showed that the instantaneous SOC is the most important factor influencing the decision to charge, while the predicted SOC at the destination affects the route choice. Charging time, proximity to the origin, and consistency with the direction of travel significantly influence the charging station selection process [37]. Users often recharge with SOCs above 50%, especially at home or work, and the availability of slow charging at the destination leads to a failure to consider the choice of fast charging [38]. The results presented in [39] show that Korean consumers prefer charging mainly during the evening at home. However, during peak hours, people favor fast public charging. Similar results were reported in an Australian survey [40]: in general, charging habits are strongly influenced by costs, and drivers prefer charging their EVs at home or work rather than at a public charging station. However, people with travel commitments involving other family members prefer using a public charging station. [PERSON] et al. [41] investigated home-charging preferences, showing that the energy required for charging has a positive marginal utility in most cases, while the charging time has a more complex influence: most users keep their vehicles in a charging state until they can remain at home and do not to finish charging if this causes delays in departure. The charging cost always has a negative marginal utility. An extensive analysis of charging behaviors in the USA [42] collected data on the location, time, and power of charge events. In total, 57% of users stated that they only charge their EVs at home, and 40% reported that they charge their EVs at home and away from home, mainly at work. Most users start charging when they plug in their vehicles, but around 20% use a timer to shift their EV load to off-peak hours. In addition, the higher the EV range, the more likely the respondent was to use public charging. A stated choice survey and willingness-to-pay (WTP) analysis confirmed home charging to be the primary charging method employed, while public infrastructure was deemed insufficient [43]. The determining factors in charging choice are price, the occupancy rate, and the waiting time at the charging facility. An acceptable distance from the destination to the charging infrastructure is a 5-10 min walking distance [43]. Another WTP analysis showed that it increases proportionally to the CP power and the CP's distance from the city center [44]. [PERSON] et al. [45] obtained similar conclusions; moreover, the lower the SOC, the more willing EV owners are to pay for charging. Attention to environmental issues emerges when investigating the positive correlation between the WTP and the portion of recharge energy from renewable sources [46]. The willingness to participate in smart-charging projects that can reduce costs and increase the share of renewable energy has also been confirmed [47]. Controlled charging is an efficient method for minimizing peak demand and maximizing the use of renewable sources while reducing costs, although privacy concerns remain [48]. For this reason, user-controlled charging is preferred over network-operator-driven charging [49]. Fast charging represents an interesting technological solution that could positively affect the diffusion of electric mobility. A stated-preferences survey on users' fast-charging choices on long-distance trips revealed that SOC and the possibility of reaching a fast station without deviations from the planned trip are the primary factors influencing charging decisions [50]. A survey of EV usage in Japan analyzed the SOC when fast charging began during road trips.