2. Literature and related work

Since 2012, studies and research projects have tackled EV adoption [10], range issues, infrastructure [15], charging loads on electricity grid [19, 41] and the use of renewable energy to charge the battery [40]. WPC practices are published as business cases or corporate reports [42] by service providers or a summary of a governmental initiative or grant or scheme announcements [20, 19, 26, 28]. These reports provide data regarding the number of CPs, locations, power capacity, service provider, billing policy, and the number of users. They lack information about operation and management, as there are no examples or practices of usability and utilisation of resources.

#### 2.1. In the UK

each EV driver is using, they each create a list of applications; Figure 4 gives examples for

There are national charging network websites (www.Zipmap,.ac.uk), Twitter hash tag (#UKCharge) and blogs (unofficial Nissan Leaf forum (www.leaftalk.co.uk)) that show updates for all CPs across the UK. The social media and the service providers' applications do not cover the privately owned recharging network, which includes the CPs allocated for particular community, company staff members or customers only. This takes us to the defini-

tion of available CPs the EV driver may find in their journeys. An available CP means:

different sets of applications 4 EV users have on their smart phones.

Figure 4. Various collections of smartphone applications EV users have.

Figure 3. Nissan leaf telematics–NISSANCONNECT EV user interface-UI.

182 New Trends in Electrical Vehicle Powertrains

1. It is working and does not report any fault;

3. It has a compatible power socket;

2. It is free, not occupied by other drivers or no queuing;

In 2013, the Secretary of State for Transport announced a series of grant schemes for plug-in vehicle charge points via the Office for Low Emission Vehicles (OLEV). The grant schemes would provide up to 75% towards the cost of installing new CPs for public sector bodies to install WPC on their estate. In total, 43 public bodies were successful and were granted various amounts (£3200.00 up to £237,000.00) in 2013 and 2014 to install CPs [28]. In the case of councils, the grant covers public CPs across the city. For example in The Open University, two CPs were installed for use by eight EV fleets. In the city of Milton Keynes, 10 staff members leased a Nissan Leaf for 18 months and were given access to three dual WPC for free. The council reported 1500 charging events for the first year with a positive EV user feedback accessing WPC. A further five CPs were installed on three sites of a major health care trust. In another part of the country, 49 fast chargers were installed and in a major city in the south, 20 dual CPs across the city were installed with different service providers in order to deal with the memberships and billing policies.

#### 2.2. In the USA

The emissions from commuters are the main driver giving workplace charging facilities a higher priority. According to [35] in Las Anglos, average employees commute over 24 miles to work generating three times the emissions of the county fleet operation (428,000 MTCO2). For that, the county requires employers with 250 employees at a site to provide charging facilities for alternative means of transport. Some studies reported some statistics on anticipated use of the network based on surveys. In one California survey, 37% of EV drivers had access to WPC [31]. California is an active region in installing WPC. In 2011, 20 case studies were released [29]. The case studies are all in California and they vary between small-scale companies. Seven companies are intermediate and four large-scale firms reaching 500 EV users. Same as in the UK, these case studies were presented in various business reports showing the installation cost and the service provider with no details on the operation and the charging practice.

access to two onsite CPs [28]. Each user was given an EV (Nissan Leaf) to personally use with free access to charging on campuses. In Northumbria University, the 12 staff members joined based on the voluntarily-based selection process. The users signed a consent form to allow the research team accessing their car's telematics service (Carwings). The study aimed at raising awareness and informing people about EVs and available charging facilities around the two campuses. The trial was followed by a survey capturing respondents' feedback and their EV

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Nevertheless the trials recruited a good number of participants and the responses were positive, the trials are not an indicator of a successful real practice. The trials can show potentials and forecasted performance or behaviour. Due to the short term of the trial and with the less exposure to driving an EV on a daily basis, understanding the WPC practice remains a nondisclosed matter. With the lack of actual data about charging patterns and user preferences, the demand of best practices and showcases is becoming an urgent matter for WPC future devel-

Unlike the case studies reported in California by [6, 29], Connor, 2014 [8] talked about the lesson learned of having a WPC for 6 years in the company he works for in Oregon, USA. Connor is a solar and electric vehicle blogger; he shared the missteps of having WPC. This practice was reported informally in a blog with an EV advocate, who was keen to share their experience with WPC. In 2008, the second trial of installing and operating a WPC took place (after the first trial in late 90's). Four 3.3 kw chargers were installed and eight employees were having EVs. Charging was for free and the slots were 50% of the time utilised. In 2011, more users joined the EV market and the charging became more difficult. The employer ran a pilot study to analyse the system and see the best strategic management approach to operate the WPC. The existing CPs were removed and new six 6.6 kW chargers and the employer applied a charging fee, \$1 per hour. This shift badly affected the utilisation of the WPC dropping to 50% use and the CPs became available. Charging the employees for using the CPs added an element of discipline to the WPC system. Users were keen to go and unplug their EVs once they are done with charging allowing others to use the bay. By 2012, the pilot was over and the charging data was collected and analysed. The employer released the new scheme, which is: Payment is per kWh (8 cent per kWh) not by hour, charging using WPC was 20% cheaper than

domestic charging and four CPs were added to have in total 11 WPC serving 60 EVs.

With the new scheme, there was no incentive to move the car once done with charging, and the users were back to bay blocking. By time, and since it is a workplace and as it is a closed population with known working hours, the EV users started to know each other. They decided to have a dashboard cards so they can contact each other and they started a company-wide forum to discuss issues. This WPC is an example of a self-regulated AM/PM shifts for charging events. The community started to grow, with some occasions of spotting an EV plugged in but not charging (using the bay to park only). With the peer pressure, these occasions became rare. With some technical problems, a software glitch was responsible to set 5 of the 11 CPs free, and

perception before and after the trial [34].

opment and strategic planning.

2.3.3. A WPC showcase in the USA

the users were back to bay blocking.

In 2013, a workplace challenge was launched by the U.S. Department of Energy covering 40 states. The partners were committed to assess their employee's demand of EV charging at the workplace and to develop and execute a plan to provide charging access. In total, 150 employers joined the challenge and some of them were providing green energy to top up the cars (charging point powered by solar energy).

From 20 case studies that were reported, the majority (80%) provides the charging for free. The billing policy was designed based on the number of the EV users commuting to the workplace. It is free of charge for companies with the capacity of (1–67 EV users) otherwise it is fee-based charging (per kWh or per hour). The common themes of these studies are the billing policy and the ratio between the number of the CPs and the EV users. The companies compete with each other to get a better environmental corporate image. Firms and public bodies install CPs at their premises to promote to carbon emissions of their employees. The UX dealing with the WPC is not a priority.

#### 2.3. WPC trials and showcase

#### 2.3.1. Shell technology centre

In 2010, an EV trial was carried out and reported. The study was to investigate the social influence regarding consumer perceptions and preferences in a technology-based workplace, Shell Technology Centre in Thornton, England. A total of 57 staff members out of 500 (medium-sized workplace) were involved in the trial and 21 out of which were interviewed. The aim of this trial was not to investigate the WPC practice; it was to examine the anticipated social influence and consumer preference for alternative means of transport. Two EVs were offered to the participants to try driving and sharing the experience with their co-workers [2]. The workplace environment was selected, as was the exposure of a limited number of staff to an actual EV served to stimulate conversations with co-workers who did not participate in the trial. It also helped exploring the social influence, peer pressure and the effect of word-ofmouth on the end user perception and preference of driving an EV.

#### 2.3.2. Future transport system

In 2013, Future Transport Systems Ltd. launched a trial (as part of the SwitchEV project) in Northumbria University. In total, (n = 12) staff members participated in the EV trial to drive an EV for 2 months, which aimed at depicting the charging patterns of the participants having access to two onsite CPs [28]. Each user was given an EV (Nissan Leaf) to personally use with free access to charging on campuses. In Northumbria University, the 12 staff members joined based on the voluntarily-based selection process. The users signed a consent form to allow the research team accessing their car's telematics service (Carwings). The study aimed at raising awareness and informing people about EVs and available charging facilities around the two campuses. The trial was followed by a survey capturing respondents' feedback and their EV perception before and after the trial [34].

Nevertheless the trials recruited a good number of participants and the responses were positive, the trials are not an indicator of a successful real practice. The trials can show potentials and forecasted performance or behaviour. Due to the short term of the trial and with the less exposure to driving an EV on a daily basis, understanding the WPC practice remains a nondisclosed matter. With the lack of actual data about charging patterns and user preferences, the demand of best practices and showcases is becoming an urgent matter for WPC future development and strategic planning.

#### 2.3.3. A WPC showcase in the USA

For that, the county requires employers with 250 employees at a site to provide charging facilities for alternative means of transport. Some studies reported some statistics on anticipated use of the network based on surveys. In one California survey, 37% of EV drivers had access to WPC [31]. California is an active region in installing WPC. In 2011, 20 case studies were released [29]. The case studies are all in California and they vary between small-scale companies. Seven companies are intermediate and four large-scale firms reaching 500 EV users. Same as in the UK, these case studies were presented in various business reports showing the installation cost and the service provider with no details on the operation and

In 2013, a workplace challenge was launched by the U.S. Department of Energy covering 40 states. The partners were committed to assess their employee's demand of EV charging at the workplace and to develop and execute a plan to provide charging access. In total, 150 employers joined the challenge and some of them were providing green energy to top up the

From 20 case studies that were reported, the majority (80%) provides the charging for free. The billing policy was designed based on the number of the EV users commuting to the workplace. It is free of charge for companies with the capacity of (1–67 EV users) otherwise it is fee-based charging (per kWh or per hour). The common themes of these studies are the billing policy and the ratio between the number of the CPs and the EV users. The companies compete with each other to get a better environmental corporate image. Firms and public bodies install CPs at their premises to promote to carbon emissions of their employees. The UX dealing with the

In 2010, an EV trial was carried out and reported. The study was to investigate the social influence regarding consumer perceptions and preferences in a technology-based workplace, Shell Technology Centre in Thornton, England. A total of 57 staff members out of 500 (medium-sized workplace) were involved in the trial and 21 out of which were interviewed. The aim of this trial was not to investigate the WPC practice; it was to examine the anticipated social influence and consumer preference for alternative means of transport. Two EVs were offered to the participants to try driving and sharing the experience with their co-workers [2]. The workplace environment was selected, as was the exposure of a limited number of staff to an actual EV served to stimulate conversations with co-workers who did not participate in the trial. It also helped exploring the social influence, peer pressure and the effect of word-of-

In 2013, Future Transport Systems Ltd. launched a trial (as part of the SwitchEV project) in Northumbria University. In total, (n = 12) staff members participated in the EV trial to drive an EV for 2 months, which aimed at depicting the charging patterns of the participants having

mouth on the end user perception and preference of driving an EV.

the charging practice.

184 New Trends in Electrical Vehicle Powertrains

WPC is not a priority.

2.3. WPC trials and showcase

2.3.1. Shell technology centre

2.3.2. Future transport system

cars (charging point powered by solar energy).

Unlike the case studies reported in California by [6, 29], Connor, 2014 [8] talked about the lesson learned of having a WPC for 6 years in the company he works for in Oregon, USA. Connor is a solar and electric vehicle blogger; he shared the missteps of having WPC. This practice was reported informally in a blog with an EV advocate, who was keen to share their experience with WPC. In 2008, the second trial of installing and operating a WPC took place (after the first trial in late 90's). Four 3.3 kw chargers were installed and eight employees were having EVs. Charging was for free and the slots were 50% of the time utilised. In 2011, more users joined the EV market and the charging became more difficult. The employer ran a pilot study to analyse the system and see the best strategic management approach to operate the WPC. The existing CPs were removed and new six 6.6 kW chargers and the employer applied a charging fee, \$1 per hour. This shift badly affected the utilisation of the WPC dropping to 50% use and the CPs became available. Charging the employees for using the CPs added an element of discipline to the WPC system. Users were keen to go and unplug their EVs once they are done with charging allowing others to use the bay. By 2012, the pilot was over and the charging data was collected and analysed. The employer released the new scheme, which is: Payment is per kWh (8 cent per kWh) not by hour, charging using WPC was 20% cheaper than domestic charging and four CPs were added to have in total 11 WPC serving 60 EVs.

With the new scheme, there was no incentive to move the car once done with charging, and the users were back to bay blocking. By time, and since it is a workplace and as it is a closed population with known working hours, the EV users started to know each other. They decided to have a dashboard cards so they can contact each other and they started a company-wide forum to discuss issues. This WPC is an example of a self-regulated AM/PM shifts for charging events. The community started to grow, with some occasions of spotting an EV plugged in but not charging (using the bay to park only). With the peer pressure, these occasions became rare. With some technical problems, a software glitch was responsible to set 5 of the 11 CPs free, and the users were back to bay blocking.

#### 2.4. Gap in the literature

The WPC context provides several unique opportunities for innovative research on social influence and preferences formation. There is a clear gap in the literature due to the lack of information about the WPC practices, access to charging data, and meeting WPC users. Assessing real world use and monitoring of a WPC system will allow the communities (user and provider) design requirements to emerge. Ethnographic studies and spatio-temporal data analytics that explore and identify the behaviour of EV users rather than their perceptions or attitude will allow actual relevant insights to emerge. Relying on anticipated behaviour or probabilistic scenarios of WPC environment would be misleading due to the special nature of this system compared to the public shared charging network and to conventional refuelling infrastructure. EV users do not have pre-existing preferences for novel attributes that they have not previously experienced [1]. Thus, some behaviours are spontaneous and constructed in the process of facing new technology [7] and allow users to examine technology affordances [38].

The latter case study illustrated the mechanism of the WPC as it was seen by one of the EV users. An insider EV user critiqued the missteps and drawbacks of the system. With a bottom up approach, an informal scheme was formed regulating the WPC system. One of the issues the EV users experienced was a practice called bay blocking. It is the phenomenon of someone, who has finished charging but has not moved their vehicle so that another user can use the CP. This phenomenon rarely occurs in publicly available CPs as the service provider charges the EV driver as long as the car is occupying the bay (as long as it is plugged in). This phenomenon influentially affects the use of WPC. The present study will be analysed and compared to this showcase interrogating any similarities between the two systems.

### 3. Methodology

The present study applies an observational research method; it is a longitudinal study in which a case study was identified and the data was gathered over a period of time [43]. This study takes a data-driven approach. Following a multi method approach, we elicited details about EV users' perceptions, social practice, interactions and charging patterns sharing the WPC at a UK research institute. The methodology was phased, spanning 12 months (March 2015–March 2016), see Figure 5. Due to the nature of the longitudinal study, it was expected that new employees join the WPC scheme while others opt out. The availability of all users throughout the phased study was not guaranteed.

In order to get factual figures about the state of the battery and the use of the WPC, participants were also asked to fill in a diary with details of date of the charging event, SOC on arrival, start and end times, and the SOC after charging. The EV diary took place in March 2015 for three consecutive weeks, where (n = 7) filled it in and returned it. In order to interrogate the charging practice, data analytics were conducted accessing the database with charging events provided by the service provider. The database included the (CP identification code, data of the charging event, starting time within the day, end time within the day and the overall kW consumed). In addition to monitoring the notifications, the EV users send charging

[1] Interview 1 EV01, EV02, EV03, EV04, EV05, EV06, EV07, EV08, EV09, EV10

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[2] EV diary 1 EV01, EV02, EV03, EV05, EV07, EV08, EV09

[5] EV diary 2 EV01, EV02, EV05, EV07, EV08, EV09, EV10

[6] Data visualisation EV01, EV05, EV07, EV08, EV09, EV10, EV11,EV12,EV13 [8] Interview 2 EV01, EV05, EV07, EV08, EV09, EV10, EV11,EV12,EV13

In February–March 2016, another EV dairy was designed to report individuals WPC charging pattern. The responses of the two dairies were compared to investigate the changes in user charging patterns during 1 year of use. To have clear insights and justification of users' behaviour, a data visualisation technique was deployed showing each charging event and the

updates to each other.

Figure 5. Methodology diagram showing the study timeframe.

Method Participants

[3, 4] All users

Table 1. Study phased methods and the involved participants.

Table 1 summarises the methods used and the involved participants in each stage. The first stage of the study was a structured interview [44] (Interview I), which was carried out in March 2015. In total, 4:07 hours were spent interviewing the (n = 10) participants. Qualitative and quantitative data was collected through open-ended questions. Table 2 summarises the EV users' profiles and relevant data. In 2015, there were 12 users registered in the WPC scheme; however, only 10 were regularly using it. In 2016, three users joined the system and one opted out to have in total 13 EV owners.

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Figure 5. Methodology diagram showing the study timeframe.

2.4. Gap in the literature

186 New Trends in Electrical Vehicle Powertrains

ances [38].

3. Methodology

the phased study was not guaranteed.

one opted out to have in total 13 EV owners.

The WPC context provides several unique opportunities for innovative research on social influence and preferences formation. There is a clear gap in the literature due to the lack of information about the WPC practices, access to charging data, and meeting WPC users. Assessing real world use and monitoring of a WPC system will allow the communities (user and provider) design requirements to emerge. Ethnographic studies and spatio-temporal data analytics that explore and identify the behaviour of EV users rather than their perceptions or attitude will allow actual relevant insights to emerge. Relying on anticipated behaviour or probabilistic scenarios of WPC environment would be misleading due to the special nature of this system compared to the public shared charging network and to conventional refuelling infrastructure. EV users do not have pre-existing preferences for novel attributes that they have not previously experienced [1]. Thus, some behaviours are spontaneous and constructed in the process of facing new technology [7] and allow users to examine technology afford-

The latter case study illustrated the mechanism of the WPC as it was seen by one of the EV users. An insider EV user critiqued the missteps and drawbacks of the system. With a bottom up approach, an informal scheme was formed regulating the WPC system. One of the issues the EV users experienced was a practice called bay blocking. It is the phenomenon of someone, who has finished charging but has not moved their vehicle so that another user can use the CP. This phenomenon rarely occurs in publicly available CPs as the service provider charges the EV driver as long as the car is occupying the bay (as long as it is plugged in). This phenomenon influentially affects the use of WPC. The present study will be analysed and compared to this

The present study applies an observational research method; it is a longitudinal study in which a case study was identified and the data was gathered over a period of time [43]. This study takes a data-driven approach. Following a multi method approach, we elicited details about EV users' perceptions, social practice, interactions and charging patterns sharing the WPC at a UK research institute. The methodology was phased, spanning 12 months (March 2015–March 2016), see Figure 5. Due to the nature of the longitudinal study, it was expected that new employees join the WPC scheme while others opt out. The availability of all users throughout

Table 1 summarises the methods used and the involved participants in each stage. The first stage of the study was a structured interview [44] (Interview I), which was carried out in March 2015. In total, 4:07 hours were spent interviewing the (n = 10) participants. Qualitative and quantitative data was collected through open-ended questions. Table 2 summarises the EV users' profiles and relevant data. In 2015, there were 12 users registered in the WPC scheme; however, only 10 were regularly using it. In 2016, three users joined the system and

showcase interrogating any similarities between the two systems.


Table 1. Study phased methods and the involved participants.

In order to get factual figures about the state of the battery and the use of the WPC, participants were also asked to fill in a diary with details of date of the charging event, SOC on arrival, start and end times, and the SOC after charging. The EV diary took place in March 2015 for three consecutive weeks, where (n = 7) filled it in and returned it. In order to interrogate the charging practice, data analytics were conducted accessing the database with charging events provided by the service provider. The database included the (CP identification code, data of the charging event, starting time within the day, end time within the day and the overall kW consumed). In addition to monitoring the notifications, the EV users send charging updates to each other.

In February–March 2016, another EV dairy was designed to report individuals WPC charging pattern. The responses of the two dairies were compared to investigate the changes in user charging patterns during 1 year of use. To have clear insights and justification of users' behaviour, a data visualisation technique was deployed showing each charging event and the


Table 2. Participants personal and EV-related information (The first user – EV01) joined in August 2014 and the newest joined in December 2014 (EV10). Some of the participants are sharing their car with their spouses (EV01, EV04 and EV11).

> The WPC is operated on a de-facto first-come, first-serve (FCFS) scheduling protocol [48]. Those who come later have to wait for the charging service in a queue [49]. However, in this case, EV users do not have a system to register and queue; they have to wait for undefined period of time when someone is done with charging so they can swap. Weeks after establishing the charging network and having more users joining the EV scheme, the users realised that the lack of communication between all the users was a barrier to efficient sharing of the charging facilities. They created a simple mean of communication to facilitate the charging process on campus. They agreed among themselves that when anyone started or stopped charging, they would send a notification message to the mailing list that indicated the estimated time for

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It all started with an email with a subject line: EV – On charge. When, we, the employer added another charging bay, the users started to indicate this in their notifications, free spaces. In 2016, the waiting bay was added in each site and users started to send notification if they are

By the time, an EV community was informally formed, and a friendly atmosphere began to appear. Not long after, more users joined the scheme, and the demand superseded the supply,

charging, see Figure 7.

Figure 6. (a)–(e). On-site WPC facilities and charging compatibility.

waiting, see Figure 8.

Figure 7. Printscreen of CYC network real-time update.

corresponding notifications sent by the user. The visualisation was used over the second interview (March 2016) as a Participatory Data Analysis (PDA) approach [45]. PDA aims to understand the human behaviour by conducting interviews in which participants interpret, justify and reflect on their own data. Devereux was the first to highlight that reflection on such personal ways of reacting can be used as a source of knowledge [46]. Interview II was semi-structured and recorded, 7:08 hours in total were spent interviewing (n = 9). As a qualitative research method, a thematic analysis was carried out of each interview to identify and report patterns (themes) within the data collected and helps interpreting various aspects of the research questions [47].

#### 3.1. Case study

The present case study covers a UK university as a one of the WPC grant successful bids. In August 2014, two CPs were installed, see Figure 6. Each CP has two ports and each port has a capacity of 32 A, in two different locations on campus. One CP is in the visitor car park near main reception to accommodate visitors and staff (site 1) while the other is in a staff car park (site 2). Since installation, a utility management company was contracted to monitor the WPC. The billing policy is that visitors, as per request, could use the system free of charge (they are loaned an RFID card). As for the staff, providing free electricity (fuel) would be considered a taxable benefit. To avoid this, an annual membership fee was charged for their cards. Users need an RFID card, which is free for visitors but costs GBP 30 per year for staff. Once the car is plugged in, the green light flashes showing that the CP is "charging", and once the charging is over, the CP keeps flashing, "charged". If the CP is not in used, it will have blue colour. Figure 6a–e shows the other side of the cable while being plugged in the car, which is controlled by the EV users.

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Figure 6. (a)–(e). On-site WPC facilities and charging compatibility.

corresponding notifications sent by the user. The visualisation was used over the second interview (March 2016) as a Participatory Data Analysis (PDA) approach [45]. PDA aims to understand the human behaviour by conducting interviews in which participants interpret, justify and reflect on their own data. Devereux was the first to highlight that reflection on such personal ways of reacting can be used as a source of knowledge [46]. Interview II was semi-structured and recorded, 7:08 hours in total were spent interviewing (n = 9). As a qualitative research method, a thematic analysis was carried out of each interview to identify and report patterns (themes) within the data collected and helps interpreting various aspects of the research questions [47].

Table 2. Participants personal and EV-related information (The first user – EV01) joined in August 2014 and the newest joined in December 2014 (EV10). Some of the participants are sharing their car with their spouses (EV01, EV04 and EV11).

User EV model Gender Purchase date Distance to work

EV1 Nissan leaf Male 54 month 3 mile EV2 Nissan leaf 2nd hand Male 26 month 6 mile EV3 LEAF Female 55 month 8 mile EV4 LEAF Male 30 month 4 mile EV5 LEAF Male 19 month 5 mile EV6 LEAF Male 15 month 6 mile EV7 LEAF Male 18 month 30 mile EV8 LEAF Female 16 month 27 mile EV9 Zoe Female 18 month 8.5 mile EV10 Zoe Female 13 month 3 mile EV11 Zoe Female 3 month 3 mile EV12 Nissan leaf Male 6 month 5 mile EV13 Hybrid Male 4 month 60 mile

188 New Trends in Electrical Vehicle Powertrains

The present case study covers a UK university as a one of the WPC grant successful bids. In August 2014, two CPs were installed, see Figure 6. Each CP has two ports and each port has a capacity of 32 A, in two different locations on campus. One CP is in the visitor car park near main reception to accommodate visitors and staff (site 1) while the other is in a staff car park (site 2). Since installation, a utility management company was contracted to monitor the WPC. The billing policy is that visitors, as per request, could use the system free of charge (they are loaned an RFID card). As for the staff, providing free electricity (fuel) would be considered a taxable benefit. To avoid this, an annual membership fee was charged for their cards. Users need an RFID card, which is free for visitors but costs GBP 30 per year for staff. Once the car is plugged in, the green light flashes showing that the CP is "charging", and once the charging is over, the CP keeps flashing, "charged". If the CP is not in used, it will have blue colour. Figure 6a–e shows the other side of the cable while being plugged in the car, which is

3.1. Case study

controlled by the EV users.

The WPC is operated on a de-facto first-come, first-serve (FCFS) scheduling protocol [48]. Those who come later have to wait for the charging service in a queue [49]. However, in this case, EV users do not have a system to register and queue; they have to wait for undefined period of time when someone is done with charging so they can swap. Weeks after establishing the charging network and having more users joining the EV scheme, the users realised that the lack of communication between all the users was a barrier to efficient sharing of the charging facilities. They created a simple mean of communication to facilitate the charging process on campus. They agreed among themselves that when anyone started or stopped charging, they would send a notification message to the mailing list that indicated the estimated time for charging, see Figure 7.

It all started with an email with a subject line: EV – On charge. When, we, the employer added another charging bay, the users started to indicate this in their notifications, free spaces. In 2016, the waiting bay was added in each site and users started to send notification if they are waiting, see Figure 8.

By the time, an EV community was informally formed, and a friendly atmosphere began to appear. Not long after, more users joined the scheme, and the demand superseded the supply,

Figure 7. Printscreen of CYC network real-time update.


• Do you see any shortcomings in the service provided? Any recommendation for an

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The social influence plays a main role in the adoption and usability of EVs [29, 28]. The motivations varied between environmental concerns, the habit of being a technology geek, long-term based financial calculations, the self-satisfaction of being an early adopters or a risk taker. The interviews showed the two main predictors of the purchase decision: domestic and

"Having access to domestic charging is compulsory; otherwise, owing an EV would not have

"I am waiting for my domestic charger to be installed next month, I only rely on the WPC for

"Some EV users rely mainly on workplaces, yet domestic charging is essential for non-work,

WPC is a cheaper, more accessible (closed population) and convenient (vehicles are parked typically for at least 8 hours during the day) option compared to public charging. Through interviews, the EV users commented on the ad-hoc email list solution they had created.

"It is a good temporal mean of communication. Surely, it will break down with more users and

"Driving an EV is a joy; however, the system is associated with socio-technical, behavioural

"It opens a channel of communication; however, it is not a platform with real-time updates."

"I do not have a smart phone, I come early after I drop off my kids at school, and charge almost

"The current practice now is based on first come first served. I am ok with that, as I have to be

"Honestly, 90% of my charging events are opportunistic!. I don't have to charge to secure my

"last week I was going to the Heathrow and I was in need to charge at the workplace, I had to send notification 2 days before asking if the Estate Department can secure a bay for me, but I didn't get a response!.. Luckily, I found a bay on the day but I was there at 7 AM!!!." [EV03]

Studying the various degrees of exposure to EV driving and technology, and the social network structure created by the community, sheds light on the WPC system dynamics and the

needs. The communication between the CPs and us deemed fundamental." [E0V2]

improvement?

been possible." [EV07]

now." [EV10]

[EV10]

WPC access. With no hesitation, the users said:

weekends, and long journeys." [EV04]

CPs, it does not scale." [EV04]

everyday morning." [EV05]

home journey" [EV01]

3.3. Data analytics (stage I)

As for the shared resources, the responses were different.

at work at 8 AM everyday. Wondering what others think!" [E0V9]

Figure 8. Printscreens of EV user notifications.

Figure 9. (a)–(d). Various notifications sent by EV users.

adding stress and competitive behaviour to the recharging process. Users started to send polite reminders asking others, who are bay blocking, to remove their EVs. Taking a community centric approach, the users created a Google-shared document, where they can log in their charging sessions. Initiatives and suggestions were brought up by the users trying to find solutions to release some of the recharging stress, Figures 9a–d.

#### 3.2. 2015 interview (round 1)

Through Interview I, the users (n = 10) were asked 24 questions classified into 5 categories: (i) EV profile, (ii) driving profile, (iii) workplace insights, (iv) HCI in EV context and (v) usability. The questions varied between qualitative and quantitative addressing questions related to their motivations of purchasing an EV, charging and driving patterns for work-based trips, WPC practice, use feedback, communication system and design recommendations. Attention was given to their insights and feedback on the use of the WPC. The questions that addressed the perceptions of shared resources were:


• Do you see any shortcomings in the service provided? Any recommendation for an improvement?

The social influence plays a main role in the adoption and usability of EVs [29, 28]. The motivations varied between environmental concerns, the habit of being a technology geek, long-term based financial calculations, the self-satisfaction of being an early adopters or a risk taker. The interviews showed the two main predictors of the purchase decision: domestic and WPC access. With no hesitation, the users said:

"Having access to domestic charging is compulsory; otherwise, owing an EV would not have been possible." [EV07]

"I am waiting for my domestic charger to be installed next month, I only rely on the WPC for now." [EV10]

"Some EV users rely mainly on workplaces, yet domestic charging is essential for non-work, weekends, and long journeys." [EV04]

WPC is a cheaper, more accessible (closed population) and convenient (vehicles are parked typically for at least 8 hours during the day) option compared to public charging. Through interviews, the EV users commented on the ad-hoc email list solution they had created.

"It is a good temporal mean of communication. Surely, it will break down with more users and CPs, it does not scale." [EV04]

"Driving an EV is a joy; however, the system is associated with socio-technical, behavioural needs. The communication between the CPs and us deemed fundamental." [E0V2]

"It opens a channel of communication; however, it is not a platform with real-time updates." [EV10]

"I do not have a smart phone, I come early after I drop off my kids at school, and charge almost everyday morning." [EV05]

As for the shared resources, the responses were different.

"The current practice now is based on first come first served. I am ok with that, as I have to be at work at 8 AM everyday. Wondering what others think!" [E0V9]

"Honestly, 90% of my charging events are opportunistic!. I don't have to charge to secure my home journey" [EV01]

"last week I was going to the Heathrow and I was in need to charge at the workplace, I had to send notification 2 days before asking if the Estate Department can secure a bay for me, but I didn't get a response!.. Luckily, I found a bay on the day but I was there at 7 AM!!!." [EV03]

#### 3.3. Data analytics (stage I)

adding stress and competitive behaviour to the recharging process. Users started to send polite reminders asking others, who are bay blocking, to remove their EVs. Taking a community centric approach, the users created a Google-shared document, where they can log in their charging sessions. Initiatives and suggestions were brought up by the users trying to find

Through Interview I, the users (n = 10) were asked 24 questions classified into 5 categories: (i) EV profile, (ii) driving profile, (iii) workplace insights, (iv) HCI in EV context and (v) usability. The questions varied between qualitative and quantitative addressing questions related to their motivations of purchasing an EV, charging and driving patterns for work-based trips, WPC practice, use feedback, communication system and design recommendations. Attention was given to their insights and feedback on the use of the WPC. The questions that addressed

• Is anyone taking a priority to charge? And if any, do you see this as a fair protocol of

solutions to release some of the recharging stress, Figures 9a–d.

• Does the current system allow you to meet your mobility demand?

3.2. 2015 interview (round 1)

Figure 8. Printscreens of EV user notifications.

190 New Trends in Electrical Vehicle Powertrains

managing the WPC?

the perceptions of shared resources were:

Figure 9. (a)–(d). Various notifications sent by EV users.

Studying the various degrees of exposure to EV driving and technology, and the social network structure created by the community, sheds light on the WPC system dynamics and the emerging social practice. The first round of the interviews provided useful and meaningful insights. Visualising users' mobility patterns helped with understanding the daily patterns, types of the journeys, denoting the daily locations of individuals (mobility demand). The EV is the second household car to all participants apart from one participant, EV10.

The interviews showed user perceptions and personal preferences; however, there was a need of actual figures that reflect how people rely on the WPC. The spatio-temporal analysis explored the charging patterns, shifts, usability and users' behaviour. Data retrieved from the CPs do not indicate the real need of charging, as it does not reflect the urgency of charging event. The data does not show if the charging event was opportunistic (the EV owner plugged in their car as the bay was available) or it was urgent to have a secured journey back home.

#### 3.3.1. Diaries

The first diary study was carried out asking the participants (n = 7) to report their state of charge (SoC) for 3 weeks. The users reported the charging sessions' timing, which was compared to the CP database for validation. In April 2015, the dairies were collected and responses were tabulated showing minimum and maximum SOC on arrival: EV02 scored the least SOC of 9%.

was not necessary for participants to recall each day we presented, the main aim of the discussion was to observe the EV users' justification for the collective behaviour being denoted in the visualisation. Some charging events were striking and the participants were able to figure why such behaviour was made by checking their personal diaries or remembering a

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Figure 11. (a), (b). Visualising of charging even and showing it to the participants over Interview I.

Each interview lasted about 50–60 minutes and took place at the participants' workplace. Each session was voice recorded and transcribed. We briefly introduced the visualisation to the participants through an enlarged and linear bar chart representing the charging events with

The interviews were conducted using 2 A4 paper sheets with their 4th quarter of 2015 charging events and a separate sheet representing the last month (15 February–15th March) of driving

The participants were asked: (1) when they send notifications to other users and (2) what kind of information they are sending over. The questions were asked over the visualisation of each user, see Figure 7. Some participants were very keen to send notifications to others; however, there was always a delay and in some occasions they forget to send at all. Only one participant accesses work email from their smartphones. As a result, there is a delay, as they have to return to their desks to send email after they plug or unplug their cars. On some occasions, this causes an inconvenience as the case of EV09. EV09 has to walk around 15-minute to reach site 1 and

The users were asked about the importance of WPC in their daily charging demand after another year of having access to it. They were asked whether they rely more now on WPC or

particular event that happened on that day.

all needed data, see Figure 11a and b.

3.4. Data participatory approach

20 minutes to reach site 2, see Figure 12.

3.4.2. Confidence level and use of WPC

3.4.1. Community action

and charging behaviour before the interview date.

"Only once, suddenly it didn't charge...only 50%." [EV07]

The second diary study was more detailed as it was asking the users about their arrival time on campus and if they needed charging everyday they are in. The users filled the diary; some of them did this manually, while others preferred to fill it in a spread sheet. Among the two diaries, there were five users in common, EV01, EV02, EV07, EV09 and EV10. The responses were compared to interrogate if there was any difference in the SOC Figure 10.

#### 3.3.2. Participatory data analysis

We conducted interviews with each participating EV user, in which we used the visualisations to help participants reflect on their previous charging patterns (2015 and 2016 diary studies). It

Figure 10. The average of SOC on arrival (2015/2016).

The Spatio-Temporal Analysis of the Use and Usability Problems of EV Workplace Charging Facilities http://dx.doi.org/10.5772/intechopen.80481 193

Figure 11. (a), (b). Visualising of charging even and showing it to the participants over Interview I.

was not necessary for participants to recall each day we presented, the main aim of the discussion was to observe the EV users' justification for the collective behaviour being denoted in the visualisation. Some charging events were striking and the participants were able to figure why such behaviour was made by checking their personal diaries or remembering a particular event that happened on that day.

#### "Only once, suddenly it didn't charge...only 50%." [EV07]

Each interview lasted about 50–60 minutes and took place at the participants' workplace. Each session was voice recorded and transcribed. We briefly introduced the visualisation to the participants through an enlarged and linear bar chart representing the charging events with all needed data, see Figure 11a and b.

The interviews were conducted using 2 A4 paper sheets with their 4th quarter of 2015 charging events and a separate sheet representing the last month (15 February–15th March) of driving and charging behaviour before the interview date.

#### 3.4. Data participatory approach

#### 3.4.1. Community action

emerging social practice. The first round of the interviews provided useful and meaningful insights. Visualising users' mobility patterns helped with understanding the daily patterns, types of the journeys, denoting the daily locations of individuals (mobility demand). The EV is

The interviews showed user perceptions and personal preferences; however, there was a need of actual figures that reflect how people rely on the WPC. The spatio-temporal analysis explored the charging patterns, shifts, usability and users' behaviour. Data retrieved from the CPs do not indicate the real need of charging, as it does not reflect the urgency of charging event. The data does not show if the charging event was opportunistic (the EV owner plugged in their car as the bay was available) or it was urgent to have a secured journey back home.

The first diary study was carried out asking the participants (n = 7) to report their state of charge (SoC) for 3 weeks. The users reported the charging sessions' timing, which was compared to the CP database for validation. In April 2015, the dairies were collected and responses were tabulated showing minimum and maximum SOC on arrival: EV02 scored the least SOC of 9%.

The second diary study was more detailed as it was asking the users about their arrival time on campus and if they needed charging everyday they are in. The users filled the diary; some of them did this manually, while others preferred to fill it in a spread sheet. Among the two diaries, there were five users in common, EV01, EV02, EV07, EV09 and EV10. The responses

We conducted interviews with each participating EV user, in which we used the visualisations to help participants reflect on their previous charging patterns (2015 and 2016 diary studies). It

were compared to interrogate if there was any difference in the SOC Figure 10.

the second household car to all participants apart from one participant, EV10.

3.3.1. Diaries

3.3.2. Participatory data analysis

192 New Trends in Electrical Vehicle Powertrains

Figure 10. The average of SOC on arrival (2015/2016).

The participants were asked: (1) when they send notifications to other users and (2) what kind of information they are sending over. The questions were asked over the visualisation of each user, see Figure 7. Some participants were very keen to send notifications to others; however, there was always a delay and in some occasions they forget to send at all. Only one participant accesses work email from their smartphones. As a result, there is a delay, as they have to return to their desks to send email after they plug or unplug their cars. On some occasions, this causes an inconvenience as the case of EV09. EV09 has to walk around 15-minute to reach site 1 and 20 minutes to reach site 2, see Figure 12.

#### 3.4.2. Confidence level and use of WPC

The users were asked about the importance of WPC in their daily charging demand after another year of having access to it. They were asked whether they rely more now on WPC or

"At work, I used to charge it more often, but I know there's a queue and because I can charge it at home. In fact I did charge it yesterday and it is on charge at the moment. Only because I had

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Bay blocking (black bar in visualisations) appeared for all participants. Some participants had short bars indicating that they were stuck in a meeting or the time it took them to go to their car. In other cases, the black bars were almost the same length of the red bars (charging), which

"I was in a meeting so I couldn't unplug it earlier." [EV10] "We are here to work not to charge the car. I am not supposed to shift a meeting to charge the car." [EV05] "I look on the dashboard how many hours for a full charge. I walk to my office, I check my calendar, and based on it, I send the estimated time. And if there is a! meeting, I will definitely extend the

The participants were asked about their opinion about the system as some of them have been using it for more than a year and others just joined early this year. The users' attitude towards the system is different and a few of them felt unwelcomed because they have hybrid cars or

"If decided to have an exact charging session, lets say…a 3 hour session from (8,30-11,30), I

"Sixty miles away from here. Without any traffic, travelling at 70 miles an hour, it takes me one hour to get here on the M25 and M1. I have to leave home with a full battery. I get here, in winter, with about 15% left. In winter I need a good five hours. If I don't get the five hours I

Throughout the interviews, the users found a chance to freely discuss and reflect on the current

"Yes. It was my idea especially when we were down to one post that we limited to an hour and a half a week per person– people said, "No, I need to charge three hours a day." [EV12]

"The charging here is a big stress, a major stress…I need 3 hrs to charge my battery!" [EV13]

Throughout the study, certain personality traits emerged, which can identify the individuals using a WPC, some of which are social (sending on-time notifications), whereas other traits are

to go out lunchtime, so I come back and there was a free space…" [EV12]

means 50% of the time the car was plugged in, and was not charging.

3.4.4. Bay blocking

3.4.5. System reflection

live close to the university.

will use it lesser." [EV09]

can't get home." [EV13]

3.5. Data analytics (stage II)

"I try to be early to charge before others." [EV07]

system. Some practical solutions were suggested.

time and go afterwards."[EV09]

Figure 12. EV09 message sent to the EV users.

they plan to opt out the scheme and rely on domestic charging. The question was asked, as by looking into the charging data retrieved from the CPs, there was variance in the total kWs used by each EV user. For the charging records of 2015, EV01, EV09 and EV10 charged equivalent to <30 GBP; whereas, EV02 charged equivalent to 60 GBP and EV05, EV07 and EV08 used kW worth over 120 GBP. The participants were asked to report their car mileage since they have joined the EV scheme.

#### 3.4.3. Charging patterns

The participants were asked about their visualised charging events and whether there is a routine, they have to stick to or they change their working hours to accommodate charging. Some users cannot make it to the workplace before 9:15 AM as they drop their kids at school. Some of those users live 30 miles away from work or the school is 20 miles away. Those users are aware that by the time they arrive, they will hardly find an available charging bay. From the charging records, those people target Noontime charging sessions. EV05 was saying:

"I do not look for a charging bay now when I arrive, I go straight to my office. Once I am on my desk, I login and keep an eye on the nearest estimated time. I mark the email with a 10 minute late reminder…I go to plug it in." [EV05]

Other users give up if they could not find a morning slot as they will be too busy to go over the day to plug it in and unplug it.

"I usually have enough in my battery to go home. So if I miss the morning session, I don't bother charging." [EV05]

Other users charge only twice a week, on Tuesdays and Fridays and with the FCFS protocol, it is becoming a hassle.

"Now realising how the charging affects my day and considering one of the charging bay wasn't working… it costs me a lot of effort to charge here."![EV09] "I don't live very far from work; however, the way we use the car is: you take the car, you do the school run." [EV10]

While most of the users are competing to charge their EVs, some users gave up their slots for those who in need to charge.

"At work, I used to charge it more often, but I know there's a queue and because I can charge it at home. In fact I did charge it yesterday and it is on charge at the moment. Only because I had to go out lunchtime, so I come back and there was a free space…" [EV12]

#### 3.4.4. Bay blocking

they plan to opt out the scheme and rely on domestic charging. The question was asked, as by looking into the charging data retrieved from the CPs, there was variance in the total kWs used by each EV user. For the charging records of 2015, EV01, EV09 and EV10 charged equivalent to <30 GBP; whereas, EV02 charged equivalent to 60 GBP and EV05, EV07 and EV08 used kW worth over 120 GBP. The participants were asked to report their car mileage since they have

The participants were asked about their visualised charging events and whether there is a routine, they have to stick to or they change their working hours to accommodate charging. Some users cannot make it to the workplace before 9:15 AM as they drop their kids at school. Some of those users live 30 miles away from work or the school is 20 miles away. Those users are aware that by the time they arrive, they will hardly find an available charging bay. From the charging records, those people target Noontime charging sessions. EV05 was saying:

"I do not look for a charging bay now when I arrive, I go straight to my office. Once I am on my desk, I login and keep an eye on the nearest estimated time. I mark the email with a 10

Other users give up if they could not find a morning slot as they will be too busy to go over the

"I usually have enough in my battery to go home. So if I miss the morning session, I don't

Other users charge only twice a week, on Tuesdays and Fridays and with the FCFS protocol, it

"Now realising how the charging affects my day and considering one of the charging bay wasn't working… it costs me a lot of effort to charge here."![EV09] "I don't live very far from work; however, the way we use the car is: you take the car, you do the school run." [EV10]

While most of the users are competing to charge their EVs, some users gave up their slots for

minute late reminder…I go to plug it in." [EV05]

joined the EV scheme.

Figure 12. EV09 message sent to the EV users.

194 New Trends in Electrical Vehicle Powertrains

3.4.3. Charging patterns

day to plug it in and unplug it.

bother charging." [EV05]

those who in need to charge.

is becoming a hassle.

Bay blocking (black bar in visualisations) appeared for all participants. Some participants had short bars indicating that they were stuck in a meeting or the time it took them to go to their car. In other cases, the black bars were almost the same length of the red bars (charging), which means 50% of the time the car was plugged in, and was not charging.

"I was in a meeting so I couldn't unplug it earlier." [EV10] "We are here to work not to charge the car. I am not supposed to shift a meeting to charge the car." [EV05] "I look on the dashboard how many hours for a full charge. I walk to my office, I check my calendar, and based on it, I send the estimated time. And if there is a! meeting, I will definitely extend the time and go afterwards."[EV09]

#### 3.4.5. System reflection

The participants were asked about their opinion about the system as some of them have been using it for more than a year and others just joined early this year. The users' attitude towards the system is different and a few of them felt unwelcomed because they have hybrid cars or live close to the university.

"If decided to have an exact charging session, lets say…a 3 hour session from (8,30-11,30), I will use it lesser." [EV09]

"I try to be early to charge before others." [EV07]

"Sixty miles away from here. Without any traffic, travelling at 70 miles an hour, it takes me one hour to get here on the M25 and M1. I have to leave home with a full battery. I get here, in winter, with about 15% left. In winter I need a good five hours. If I don't get the five hours I can't get home." [EV13]

Throughout the interviews, the users found a chance to freely discuss and reflect on the current system. Some practical solutions were suggested.

"Yes. It was my idea especially when we were down to one post that we limited to an hour and a half a week per person– people said, "No, I need to charge three hours a day." [EV12]

"The charging here is a big stress, a major stress…I need 3 hrs to charge my battery!" [EV13]

#### 3.5. Data analytics (stage II)

Throughout the study, certain personality traits emerged, which can identify the individuals using a WPC, some of which are social (sending on-time notifications), whereas other traits are anti-social (bay blocking). Via interpreting the records reported in the dairies and the critical analysis of the interviews' responses, a WPC user will have at least three qualities of the following seven, as one quality in each criterion: mentality, priority and requirements. A WPC user maybe a considerate person, who cares about other EV owners sharing the limited resources with them or a selfish user, who cares about his convenience and charging needs. Each WPC user would also set a priority; whether they will put their work as a priority (e.g. they will not change anything in their work habit to accommodate shared charging), they will not shift a meeting or reschedule it to avoid bay blocking; however, they will try to avoid this as much as they can and they will show remorse for doing so. The third trait is that they will not stay in the system if it adds more pressure to their daily life and will leave the WPC scheme and go back to rely mainly on domestic charging. The last criterion is the requirements. Each WPC user would have a vision in mind for the ideal fair and efficient WPC system. These requirements vary; some users demand advanced ubiquitous computing, looking for interactive mobile applications that bring ease to their charging process; whereas, others still prefer an intuitive WPC system that requires less computer involvement.

#### 3.6. Observations and discussion(s)

When studying WPC for emerging vehicle technology, neglecting social influence processes will ignore or underestimate the potential for consumer perceptions to develop and shift. Analysing WPC systems shows cases of variant consumer personas, charging behaviour, and the need of the WPC as part of the daily routine. Charging behaviour is the collective behaviour, the EV user performs. It is the charging session they try to get, the arrival time, the time they send updates to others, the state of charge, the state of the charging point, and the time they are plugged in versus the actual charging time. It is the emergent behaviour of sharing WPC. Thus, based on this study, we cannot confidently approve the preposition of "WPC adds flexibility to work day and shall double the daily range". The WPC infrastructure is intrinsic to certain EV users, who are ready to deal with the social dynamics associated with it. A WPC system is not a prototype of a public charging network at a smaller scale, and it is a subset of an e-mobility system that has its own unique paradigms, policies and conditions.

3.6.1.1. The inseparable

Figure 13. EV WPC personas.

stressful to them as to others (Figure 14).

Figure 14. EV09 message sent to the EV users.

This persona describes the EV users (EV04, EV07, EV10 and EV12), who are very considerate to other users, who are sharing the WPC. They demand daily or at least three times a week WPC. They usually arrive at work with a relative low battery (10–20%). Due to their high demand, they make sure they deserve a secured access to WPC. Even though, the system is managed with a FCFS protocol, they manage to schedule their day to make sure they charge. They abide themselves with the communication system giving a chance to whom in demand. They notify others once they are plugged in/unplugged and may bay block in late occasions. This persona is not likable within the EV community, as they believe they take advantage due to their flexible time schedule or that they live locally, so that recharging their batteries is not as

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#### 3.6.1. A. RQ1: The four WPC user personas

In a previous study that was carried out covering different sample sizes of EV users [50], three personas were created: the old school, the risk taker and the opportunistic. The old school is the EV user, who is still afraid to have a flat battery so they are over protective and very conservative in their charging pattern. The risk taker is the EV user, who extends their driving range by exploring irregular road trips relying on public CPs. The opportunistic are the EV driver, who does not own an EV but drive fleet EV and promote car sharing as a way to be environmentally aware. These personas fit typical EV users; however, the WPC users have different personas due to various factors: shared resources protocol, peer pressure, selfishness, competition mode, priorities of individuals and work-related arrangements, which are associated with the charging process. The human aspect and the social interactions created different personas that can identity different WPC users. Four personas are generated from exploring the WPC social practice, see Figure 13.

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Figure 13. EV WPC personas.

anti-social (bay blocking). Via interpreting the records reported in the dairies and the critical analysis of the interviews' responses, a WPC user will have at least three qualities of the following seven, as one quality in each criterion: mentality, priority and requirements. A WPC user maybe a considerate person, who cares about other EV owners sharing the limited resources with them or a selfish user, who cares about his convenience and charging needs. Each WPC user would also set a priority; whether they will put their work as a priority (e.g. they will not change anything in their work habit to accommodate shared charging), they will not shift a meeting or reschedule it to avoid bay blocking; however, they will try to avoid this as much as they can and they will show remorse for doing so. The third trait is that they will not stay in the system if it adds more pressure to their daily life and will leave the WPC scheme and go back to rely mainly on domestic charging. The last criterion is the requirements. Each WPC user would have a vision in mind for the ideal fair and efficient WPC system. These requirements vary; some users demand advanced ubiquitous computing, looking for interactive mobile applications that bring ease to their charging process; whereas, others still prefer an

When studying WPC for emerging vehicle technology, neglecting social influence processes will ignore or underestimate the potential for consumer perceptions to develop and shift. Analysing WPC systems shows cases of variant consumer personas, charging behaviour, and the need of the WPC as part of the daily routine. Charging behaviour is the collective behaviour, the EV user performs. It is the charging session they try to get, the arrival time, the time they send updates to others, the state of charge, the state of the charging point, and the time they are plugged in versus the actual charging time. It is the emergent behaviour of sharing WPC. Thus, based on this study, we cannot confidently approve the preposition of "WPC adds flexibility to work day and shall double the daily range". The WPC infrastructure is intrinsic to certain EV users, who are ready to deal with the social dynamics associated with it. A WPC system is not a prototype of a public charging network at a smaller scale, and it is a subset of

an e-mobility system that has its own unique paradigms, policies and conditions.

In a previous study that was carried out covering different sample sizes of EV users [50], three personas were created: the old school, the risk taker and the opportunistic. The old school is the EV user, who is still afraid to have a flat battery so they are over protective and very conservative in their charging pattern. The risk taker is the EV user, who extends their driving range by exploring irregular road trips relying on public CPs. The opportunistic are the EV driver, who does not own an EV but drive fleet EV and promote car sharing as a way to be environmentally aware. These personas fit typical EV users; however, the WPC users have different personas due to various factors: shared resources protocol, peer pressure, selfishness, competition mode, priorities of individuals and work-related arrangements, which are associated with the charging process. The human aspect and the social interactions created different personas that can identity different WPC users. Four personas are generated from exploring

intuitive WPC system that requires less computer involvement.

3.6. Observations and discussion(s)

196 New Trends in Electrical Vehicle Powertrains

3.6.1. A. RQ1: The four WPC user personas

the WPC social practice, see Figure 13.

#### 3.6.1.1. The inseparable

This persona describes the EV users (EV04, EV07, EV10 and EV12), who are very considerate to other users, who are sharing the WPC. They demand daily or at least three times a week WPC. They usually arrive at work with a relative low battery (10–20%). Due to their high demand, they make sure they deserve a secured access to WPC. Even though, the system is managed with a FCFS protocol, they manage to schedule their day to make sure they charge. They abide themselves with the communication system giving a chance to whom in demand. They notify others once they are plugged in/unplugged and may bay block in late occasions. This persona is not likable within the EV community, as they believe they take advantage due to their flexible time schedule or that they live locally, so that recharging their batteries is not as stressful to them as to others (Figure 14).

Figure 14. EV09 message sent to the EV users.

#### 3.6.1.2. The diligent

The diligent persona is the EV user, who would try to charge at the WPC if the charging would fit within their work routine (EV01, EV06, EV09 and EV11). They are not going to change their daily routine. They arrive to the workplace with an average of (40–50%) as their charging demand is not as high as the Decent persona. Those users tend to be more active in the EV forum and open channels with the employer to discuss solutions and alternatives. They keep reminding other users not to bay block or to update their charging records. They are considered as system administrators.

• System assessment: Relying on the WPC retrieved data is misleading especially in the kW

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Ev is still in an early technology adoption stage; it has not yet taken the role of main stream of major daily transportation option [51]. We cannot confidently approve the preposition of "WPC adds flexibility to work day and shall double the daily range" [9]. The WPC infrastructure is intrinsic to certain EV users, who are ready to deal with the social dynamics associated with it. A WPC system is not a prototype of a public charging network at a smaller scale, and it is a subset of an e-mobility system that has its own unique paradigms, policies and conditions. This is an ongoing research; the next step is to analyse the social practice with more users joining the scheme and testing different simulation scenarios for the scheduling protocol.

The author would like to thank MK: Smart Research Project team at the Open University for supporting this research and all EV participants who were involved throughout the study.

[1] Xydas E, Marmaras C, Cipcigan LM, Jenkins N, Carroll S, Barker M. A data-driven approach for characterising the charging demand of electric vehicles: A UK case study.

[2] Harrison G, Thiel C. An exploratory policy analysis of electric vehicle sales competition and sensitivity to infrastructure in Europe. Technological Forecasting and Social Change.

[3] Beeton D. EV City Casebook\_50 Big Ideas Shaping the Future of Electric Mobility. 1st ed.

Vol. 2. Newcastle Upon Tyne, UK: Urban Foresight Ltd; 2014. p. 74

calculations. Interviewing EV users justifies unexplained behaviour.

• Peer pressure: may only reduce anti-social incidences.

Address all correspondence to: elbanhawy@brookes.ac.uk

Oxford Brookes University, Oxford, UK

Applied Energy. 2015;162:763-771

2016;114:165-178

4. Conclusion

Acknowledgements

Author details

Eiman Elbanhawy

References

#### 3.6.1.3. The saver

This persona includes EVowners (EV02, EV03 and EV05), who are very close to being opportunistic users. They may not need to charge at all at the WPC. However, this persona includes risk takers, who can extend their comfort zone reaching a very low SoC. Their confidence level has increased by the time they use the car. They are confident enough to reach the workplace with one cell or even zero cells left in their batteries. Due to their local commute, they are familiar with the work journey to an extent that they can confidently leave home with only 5 miles left in their battery knowing that they will charge at the WPC. They are more flexible compared to the Diligent persona as they can slightly shift their work patterns to accommodate charging. They charge at their ease, they do not pay attention to the communication pool, they check if they miss morning shift.

#### 3.6.1.4. The blacklisted

This persona includes EV owners (EV08 and EV13) whom their charging matter is not seen as urgent as others. This persona includes those who have hybrid, so relying on petrol is an option. Although they have the same right as other users, the community may stigmatised them as their case is not as critical as full electric users. Also this persona includes those who are against the suggestions for limiting the charging sessions, as this does not fit their mobility demand. They do not commute to work five times a week and live relatively far from their workplace. They do not bay block, yet they make good use of the system and charge at work very frequently. (EV08 used kW worth over 120 GBP). This persona is the least flexible compared to other personas due to mobility demand.

#### 3.6.2. B. RQ2: Usability and related issues: recommendations for assessment and design of new WPC system

There is no definite theory that controls the use of WPC, analysing the current WPCformulated lesson learned informing the design of future technologies that can improve the away from home charging experience:

