KIEAE Journal

If the long charging time, the weakness of electric vehicles cannot be decreased to the time of general vehicles, we hypothesized that the quality of waiting time would affect the satisfaction of a charging facility and designed the following research model.

Fig. 1.  
Research Model

In order to understand the circumstances of current electric vehicle charging facilities and to examine effective ways to make use of the waiting time during the charging, we established the following hypotheses.

A1. The decrease in charging time will increase the preference for electric vehicles and their charging facilities.
A2. The preference will be affected by the service provided by the charging facility.

The interview was comprised of one question regarding the environment of charging and the charging facilities and two questions regarding user resting behaviors at the facilities.

The electric vehicle charging facilities in Europe countries such as U.K., Germany, France and Belgium employ the pole-type slow chargers, which we believe is because of unfavorable conditions such as old buildings and narrow streets for setting up high power transmission facilities. The electric vehicle charging facilities in Europe are operated in the street parking lots as is seen in Fig. 2. Their names are ‘Juice Point’ in U.K., ‘RWE’ in Germany, ‘autolib’ in France and ‘Elektrobay’ (basically the same company as Juice Point) in Belgium and they are fairly noticeable on the streets.⁶⁾ Due to the limited space, there are no space for resting and the type, the shape, the setting environment and the quantities of the chargers are summarized as follows.

Fig. 2.  
European countries slow charger

The type of electric vehicle charging facilities in USA are varied and each local charging facility has its own module according to its surroundings as is seen in Fig 3. Santa Clara, California and Chicago, one of the cities with the most electric vehicle users in USA have applied ‘Charge Point’ system in operating their facilities.⁷⁾ Also, depending on its location, some have shelter-type solar energy panel with them to realize environmentally friendly energy.⁸⁾ Many of charging facilities in Santa Clara are in the form of both shelter-type and bench-type, which we assume is because it has lower building density than other cities. Also, we believe the weather in California affected the facilities to take the shelter or the awning shape. It seems that the location and its surroundings of a charging facility are closely related to its form. Table 3 summarizes what have been discussed above.

Fig. 3.  
American region Charger

The electric vehicle charging facilities in Japan and China are not common, which is similar to Korea. Therefore, it is premature to discuss the resting and the convenience in the facilities’ surrounding s⁹⁾. It seems that Japan and China are going through examining the operation systems of charging facilities¹⁰⁾ and thus their status doesn’t seem so much different than Korean as is seen in Table 4.

We conducted the one to one interviews to 23 men and women including the participants of ‘Electric Vehicle Sharing Projects’ by the Ministry of Knowledge and Economy, the users of government electric vehicles provided by Seoul city, the users of corporate electric vehicles of Korea Electric Power Corp and the taxi drivers for the handicapped of Seoul city from November 1th, 2012 to November 30th, 2012. The interview, of which results are summarized in table 9 to 11, was to figure out electric vehicle charging facility users’ behavior during the two types of waiting time, fast charging and slow charging. The interviewee demographics were 5 men in their 20’s, 10 men in their 30’s, 3 men in their 40’s, 3 women in their 20’s, 1 woman in her 30’s, 1 woman in her 40’s. 11 of them were working for corporations, 6 for governments, 3 were students, 2 were taxi drivers and 1 person was a doctor. 10 of them had experienced electric vehicles through participating in the sharing projects, 6 through governments, 5 through corporation, 2 through taxi driving, and the majority of them except for the two taxi drivers, answered that they had driven them within the city and used fast charging most of the time.

The analysis of interview results are summarized in the table 12. The interviewees were asked about 4 issues including inconveniences in using the facilities, users’ behavior during the waiting time, things to improve. In cases of slow charging, which takes 6 to 8 hours, since it is highly likely that the users charge their cars after work or during their long off-time and thus there is virtually no waiting time, we didn’t include it in our analysis. In terms of waiting time for fast charging, most frequent user behavior was web surfing through smart phones followed by watching DMB, having drinks (coffee, juice and water), smoking, using toilets. The taxi drivers and corporate or government vehicle users answered that they spent the time calculating routes based on the locations of the electric charging facilities, maintaining or washing their vehicles. 19 respondents said that due to the absence of facility signs they had difficulties finding the locations when navigations finished before destinations. Respondents said that it was inside the cars where they web surfed, had drinks and read magazines during the waiting time and the reason they did so seems because there were no resting areas. 20 out of 23 interviewees answered that sitting areas such as lounge style and awning or shelter type should be established. Also, it seems that users’ expectations for the waiting time at the charging facilities are high because of their prior similar experiences of the waiting time at resting areas in gas stations¹¹⁾ and auto repair shops.

According to Table 13, 21 out of 23 had decided to stay inside their vehicle and this seems because resting facilities were unavailable. Also, most of those who answered they use their smart phones to kill the waiting time web surfing, watching DMB or using SNS messenger were in their 20’s or 30’s, which seems because there were very few interview sources in their 40’s. It seems that the reason why the use of a smart phone is most frequent regardless of age is because of the lack of killing-time contents for the waiting time. 17 people out of 23 selected having drinks, the third most frequent behavior, for which the use of a vending machine and a bench is expected. Washing cars and using toilets are excluded from our analysis since they are not exclusive behaviors to the vehicle charging facilities,

The hypothesis A1 “The decrease in charging time will increase the preference for electric vehicles and their charging facilities” assumes that the length of the waiting time affects users’ preference for electric vehicles and its charging facilities. The user behaviors during the 30 minutes of waiting time were analyzed based on the data from 21 facilities and 23 interviews, which is summarized in Table 14. 91.3% respondents answered that the facility needs a separated resting area. 65.2% respondents wanted a sitting area. 86.9% the people said that they used a smart phone for web surfing, watching DMB and SNS messenger during the waiting time, which illustrates that users want to spend the waiting time, realistically impossible to reduce, more wisely. In other words, there is a close relationship between the reduction of the charging time and the preference for electric vehicle charging facilities and providing ways to spend the waiting time more effectively will increase the preference.

The hypothesis A2 “The preference will be affected by the service provided by the charging facility” assumes the fact that the service provided by the charging facility to help users to make use of their waiting time better affects the frequency of using the charging facility. According to the interviews, 39.1% respondents said that vending machines for drinks are needed and 43.4% interviewees answered that the facility needs an awning area. Also, 82.6% said that they have drinks while waiting and 86.9% said they spent time using their smart phones. These facts illustrate that the facility itself is not providing any subsidiary facilities. If additional services become available from the facility, it is likely that the electric car charging will be preferred. To sum up, as a result of the analysis of the interview responses, the two hypotheses above seem to be valid.