One of the challenges for battery electric vehicle (BEV) acceptance is autonomy for long trips, also known as “range anxiety”. To tackle this issue, new hardware and software features providing strategies to enable the execution of long trips by BEVs were developed within the Connected Electric Vehicle Optimized for Life, Value, Efficiency and Range (CEVOLVER) project. More specifically, the project tackled the challenge of executing long trips in a reasonable time with a small battery capacity. This was achieved by using the features under study to try to increase battery autonomy and therefore optimize the execution of long trips without changing the battery itself. Such features are user oriented, such as eco-routing, eco-charging, and eco-driving. The project considered an approach based on users’ experiences in different use cases to improve the comfort and usability of BEVs for long day trips. While it can be beneficial for reducing range anxiety, adding such features might have an impact on the overall cost of ownership and on the environmental performance of the vehicle. If not beneficial, especially in terms of cost, it could hinder the acceptance of BEVs with such solutions. This paper therefore focuses on the economic and environmental impacts of the features during the vehicle’s ownership. The assessment includes the total cost of ownership (TCO) and external costs analysis regarding greenhouse gas emissions. The technological developments are compared to the baseline vehicles.
1.1. Range Anxiety and Technological Developments to Increase Battery Autonomy
While BEVs could help improve the environmental performances of the transport sector, their growth is facing some challenges. The main reasons hindering BEV acceptance from consumers’ perspectives are range anxiety and the potential lack of charging infrastructure [
1,
2,
3,
4,
5,
6,
7].
Range anxiety is a challenge that starts with its own definition, which can vary from one study to another, leading to different interpretations of how to tackle it. While Liu et al. (2023) state that range anxiety refers more to “energy replenishment” anxiety and estimate that it is the main problem to solve [
1], Rainieri et al. (2023) mention that one of the main sources of range anxiety is individual characteristics [
5]. Regarding Franke et al. (2016) [
2], the study defines range anxiety as “range stress”, which is related to the fact that the resources to overcome the range are insufficient. However, these studies tend to agree on the fact that most BEVs available on the market can meet most consumers’ travel needs [
1,
2,
4,
5,
8]. Liu et al. (2023) go even a bit further by stating that ultra-long-range BEVs are actually not needed as they does not solve the problem of energy replenishment anxiety [
1]. Furthermore, such cars raise the cost of BEVs due to high purchase and insurance costs, which can also hinder their acceptance. Using TCO and considering range anxiety, the study establishes that the optimal range would be 400 km. The study therefore states that the current BEV market could be sufficient for more than 98% of consumers’ needs. Needell et al. (2016) also found that most existing and affordable vehicles can be sufficient to meet the energy needs of 87% of vehicle days in the United States [
8]. Such findings are contradictory to the trend from the transport sector to produce BEVs with longer ranges [
1]. Indeed, to face range anxiety issues, automotive companies are increasing the range of BEVs by increasing battery capacity and developing charging infrastructure, including fast charging. Those solutions come with some burden. Increasing battery capacity comes with different issues such as the rising cost of BEVs and also an increasing demand for critical materials such as cobalt, nickel, graphite, and lithium [
1]. Regarding improving charging infrastructure, He et al. (2023) also pinpoints the fact that its growth depends on the adoption of EVs, as stakeholders are more reluctant to develop charging facilities without growing demand [
3].
Several other solutions exist to tackle range anxiety challenges that do not necessarily involve changing the cars on the market. When range anxiety is defined by range stress or individual characteristics, the consensus is that learning experiences and range tolerance help to overcome the stress of not being able to reach a destination [
2,
3,
6]. Other solutions are more technical and practical and are the focus of this paper. One main reason for range anxiety is the unreliability of autonomy and the variation of driving range throughout the usage of the vehicle [
4,
6]. Predictive models that can provide a more accurate range prediction for vehicles will help in that context. The accuracy is enhanced by collecting more parameters such as on-route data on traffic conditions and battery conditions [
7,
9,
10]. In CEVOLVER, the feature that tackles a part of this issue is eco-charging, which uses real traffic conditions and is explained in more detail in
Section 1.2. Another solution is to reduce the energy consumption of the vehicle. It can be achieved through thermal management systems that also help to enhance the life span of the battery. As assessed by Biswas (2020) [
11], such systems generally include Heating, Ventilation and Air Conditioning (HVAC); Battery Management System (BMS); and Traction Cooling System (TCS). They ensure the optimal operating condition of the components based on their thermal efficiencies. Finally, eco-driving also helps reduce energy consumption for a certain trip [
12]. It can be achieved through learning experiences and/or with advice while driving, such as suggested speed [
13,
14,
15]. As for the driving range estimations, such add-on’s accuracy benefit from on-route information and battery parameters [
14,
15]. Another possibility for enhancing eco-driving is vehicle platooning [
16,
17], but such technological advancement is still at an experimental stage.
When analyzed in the literature, the solutions’ effectiveness in the studies is assessed through energy consumption gains, tested or simulated. It is not evaluated in terms of cost or environmental performances, which could be helpful to assess the effects on overall usage and to quantify possible burdens. When considering TCO and externalities analysis, the method is often used to compare costs of BEVs or alternative vehicles with equivalent Internal Combustion Engine Vehicles (ICEVs) [
18,
19,
20,
21,
22,
23,
24]. However, some studies [
1,
25] quantified the economic performances to qualify the necessity of longer-range BEVs. As mentioned, Liu et al. (2023) calculated the TCO of BEVs with different ranges [
1]. The study considers the battery replacement needs for a certain usage, which will differentiate between smaller and bigger EVs. The study shows that despite the battery replacement, the TCO is higher for higher electric range BEVs. Pfriem et al. (2013) found similar results for commercial fleet usage [
25]. The TCO for the fleet is beneficial compared to commercial ICEVs when using small-range BEVs. Such studies used the TCO to promote the cost benefit of short-range BEVs and to question the actual need of long-range BEVs.
In this paper, the features under study are assessed in terms of economic and environmental aspects, also including the use of energy consumption data from testing under real driving conditions on open roads or test benches. This is because while the features might be successful in terms of executing longer trips without additional time, some burden in terms of costs or environmental performances might appear and hinder the application of such features. The quantification of the effect on costs will allow assessment of the significance of the potential burdens or benefits compared to the objectives of executing the longer trips on time. Furthermore, the emphasis on the cost and environmental potential benefit might help with the overall acceptance of BEVs with smaller battery sizes.
The next section will present the features and the system evaluated during the project.
1.2. System Description
The system includes three different parameters: the vehicle, the features tested and the use case. During the CEVOLVER project, six features were tested on three different vehicles in different use cases:
One light commercial vehicle (LCV) with a 68 kWh battery;
One passenger car with a 24 kWh battery (car 1);
One passenger car with a 42 kWh battery (car 2).
The two passenger cars are identical except for the battery capacity. The baseline vehicle is defined as the vehicle without the CEVOLVER features switched on.
Table 1 summarizes the systems considered for the experiments with the baseline vehicles, the corresponding use case, and the specific features switched on during testing. Each line of the table refers to one test that has been performed, once with the features not used and once with the features switched on. Thermal-related features have been tested on test benches and the others on open roads.
The use case describes the type of usage the vehicle faces and sets the boundaries of the experiments (i.e., the type of trips completed). The “parcel service daily job” means the vehicle is used for parcel delivery, mainly in urban areas. The charging of the vehicle is performed after returning to the distribution center. The “Regular travel to and from work” refers to a short-range trip from work to home, with a distance of 30 km. The charging is executed after arriving home at a charging station. The “private visit of 350 km” refers to occasional visits to relatives during the weekend or holiday trips. Since the trip is long, this use case assumes that one fast charging is required at a public charging station and one home charging during the visit.
As for the features, eco-charging determines the most energy- and time-efficient charging and routing strategy for the trip based on traffic conditions. Different parameters are considered, including traffic and weather conditions, which enhance the accuracy of such development. Still, the real value-add comes with the intelligent recommendation for fast charging that is optimized based on the assessment of the overall trip and not just the need to find the next charging station when the state of charge drops below a set value. The functionality of the feature is detailed in De Nunzio et al. (2020) [
7]. Eco-driving ensures the speed recommendation to optimize energy consumption according to an analysis of the route and traffic conditions. The specificities are detailed in Ngo et al. (2021) [
26]. In addition, smart fast charging conditions the battery before a fast charge to ensure the full charging power is available. It prevents the battery from overheating, which would lead to a longer charging time. The driving and charging conditions are based on the data gathered from the eco-charging features. The predictive thermal powertrain optimizes the use of the powertrain components based on their thermal efficiency, and the predictive thermal cabin conditioning ensures a comfortable cabin temperature while reducing the energy consumption from the climatization system. The software development is detailed in Wahl et al. (2022) [
27] and in Chen et al. (2020) [
28]. Finally, the advanced heat pump system developed in the project OPTEMUS allows the use of heat from electric components and batteries to warm up the cabin as described in the project website and in Ferraris et al. (2020) [
29,
30].