1. Introduction
The automobile industry has become a major player in both the global economy and the world of Research and Development (R&D). With the constant advancement of technology, vehicles are now equipped with features that prioritize the safety of both passengers and pedestrians
[1]. This has led to an increase in the number of vehicles on the road, providing us with the convenience of quick and comfortable travel. However, this progress has come at a cost. Urban areas have seen a sharp rise in environmental contaminants such as sulfur dioxide (SO
2), nitrogen oxides (NOX), carbon monoxide (CO), and particulate matter (PM)
[2]. It is important to acknowledge the impact that the automobile industry has had on our daily lives, both positive and negative. While industry has brought about significant advancements in technology and transportation, it has also contributed to the deterioration of our environment. As people continue to move forward, people must prioritize finding solutions to mitigate the negative effects of the automobile industry on our planet.
It is commonly acknowledged that the earth faces growing hazards from carbon emissions and the availability of oil. Regarding energy users, the transport industry has the largest overall environmental effect, contributing more than 25% of the world’s energy usage and greenhouse gas emissions. Road transport accounts for over 70% of the sector’s emissions
[3,4][3][4]. To find answers to the problems of dependency on oil and emissions reduction, the concept of “sustainable transportation” has been promoted
[5]. The Electric Power Research Institute (EPRI) claims that even in contrast to more efficient conventional vehicles, the widespread use of EVs would considerably reduce greenhouse gas emissions
[6]. Additionally, EVs on “tank to-wheels” often have an efficiency three times greater than those powered by internal combustion engines. (ICVs). Additionally, noise and vibration are reduced with electric automobiles
[7,8,9][7][8][9].
Due to its benefits and the immediate need to tackle climate change and energy stability, several nations are promoting EVs. More than 275,000 plug-in electric vehicles (PEVs) are currently on the road countrywide in the United States, a considerable increase in PEV deployment since 2011
[10,11][10][11]. Since the introduction of EVs to the market in 2010, their sales have quadrupled annually in Europe, and by 2013, approximately 60,000 PEVs had been sold. As of September 2021, more than 2 million electric vehicles had been sold in Europe
[12]. China, the fastest-growing country in terms of EVs, has set a target of having electric vehicles (EVs) account for 20% of total new car sales by 2025. The government has also set a longer-term target of having all new cars sold in China be “new energy” vehicles (NEVs), which include both pure electric and plug-in hybrid cars, by 2035
[13].
Nevertheless, despite this marketing approach and the numerous advantages of EVs, their market share in terms of overall sales is still tiny, with EVs accounting for only 14% of all passenger cars purchased globally
[14]. One of several obstacles that must be removed for EVs to become widely used is their undeveloped battery technology. EVs are less appealing to the typical customer because of their limited range, lengthy charging periods, and expensive upfront prices
[15]. The limited availability of charging infrastructure is another significant obstacle to the widespread adoption of EVs
[16]. Establishing EV infrastructure is challenging because of the well-known “chicken-and-egg problem”. Many drivers won’t pick EVs unless a significant infrastructure for charging them is established. But if there aren’t enough EVs on the road, it’s highly doubtful that charging service providers would make significant investments in infrastructure development
[9].
High-quality services are urgently required to resolve these challenging problems, specifically to enable EVs to capture the market, and states will, of course, do a crucial job in establishing the EV industry
[17]. Recent studies have focused on various service operations issues that are considered important in driving the growth of the EV industry. For instance, how innovative business models might succeed long-term, how governments should encourage the EV market through incentive programs, and how charging infrastructures can be built to satisfy consumer needs while minimizing social costs
[18,19][18][19].
However, the massive increase in the use of electric cars has brought up several difficulties, issues, uncertainties, and concerns, including the high cost of infrastructure, the price of electric vehicles, the scarcity of charging stations, and the limited range of electric vehicles. Batteries continue to be the most significant issue. In the subsequent years, EVs will be a considerable component of smart cities, along with interconnected transportation, public transit, and other elements. Therefore, more effort is needed to improve batteries and simplify the charging process. The main problem with EVs is their autonomy. Scientists are developing better battery technology to increase driving range while reducing weight, cost, and charging time.
2. Electric Vehicles: Benefits, Challenges, and Potential Solutions for Widespread Adaptation
2.1. Smart City
A smart city is a settled region employing multiple technology devices and sensors to collect data. Smart cities manage public resources to enhance the quality of services while putting comfort, maintenance, and sustainability first by using information and communication technology (ICT)
[20].
EVs, which include electric cars, electric buses, and neighborhood electric vehicles, will soon dominate the transportation industry. The whole transit system will be electrified within the general trend of lowering petrol emissions in the city
[21,22][21][22]. However, the effectiveness of these new transportation systems cannot be assured in a typical metropolis due to new issues in power distribution and traffic management. Consequently, a smart city can aid in realizing this national goal
[23].
Electric vehicles are a crucial part of many smart city programs; hence, smart cities and electric automobiles are closely connected
[24]. One of the main objectives of many smart city initiatives is to drastically cut emissions and enhance the air quality in urban areas through the widespread use of electric cars. Electric vehicles, which require less maintenance and have lower operating expenses than conventional vehicles, also help smart cities become more efficient. Additionally, infrastructure designed for smart cities, such as smart traffic control systems and charging stations, can facilitate the adoption and integration of electric vehicles
[25].
Nevertheless, integrating electric cars into smart cities is not without its difficulties. The expense of electric cars and the infrastructure for charging them, which may be expensive and need a substantial investment, is one of the key problems. Additionally, some locals may worry about running out of energy due to the short range of electric vehicles. Guarantee that the infrastructure for charging matches residents’ demands; this necessitates thorough planning and supervision. To guarantee that electric cars are successfully and efficiently integrated into smart city infrastructure, another difficulty is the requirement for coordination and collaboration between several stakeholders, including the government, companies, and people
[23,26][23][26].
Urban areas might become more effective, sustainable, and livable because of the development of smart cities
[25]. However, cities must solve the implementation issues to ensure efficiency and equity. Cities can successfully implement smart city initiatives and reap their advantages by investing in technology and data management, creating strict privacy and cybersecurity policies and protocols, working effectively with stakeholders, and creating inclusive and accessible initiatives
[27,28][27][28].
2.2. Intelligent Transportation Systems Overview
An Intelligent Transportation System (ITS) that can accommodate their transportation needs is necessary for smart cities. For better public transportation services, transportation in a smart city should be hassle-free, environmentally friendly, and comprise networked and shared vehicles. The electric vehicle (EV), which also solves the world’s energy problems, is the finest option. Autonomous electric vehicles (AEVs), or intelligent electric vehicles, offer the linked and shared layer needed for a smart city
[29,30][29][30].
New guidelines for limiting carbon emissions (CEs) in the transit industry have been recommended, considering the rise of smart cities. Intelligent transportation systems (ITS) resolve the issues of traffic congestion and carbon emissions brought on by the sharp rise in the number of cars. (ITS). The main subject of the study is the impact of ITS installation on transportation networks’ ability to save energy and reduce emissions (ECER)
[31]. Traditional transportation infrastructure is combined with advancements in information technology, communications, sensors, controls, and sophisticated mathematical techniques to create ITS. Over the past few decades, ITS has been created and deployed to increase productivity, lower carbon emissions, enhance sustainable transportation, and increase mobility and traffic safety
[32,33][32][33].
Various factors, including an inappropriately designed urban road network, problematic functional and structural components of the road system, a lack of facilities for traffic management, and poor management levels, lead the total volume of urban traffic in different nations to deviate significantly from the optimum state. Urban traffic congestion issues, repeated traffic accidents, and increased noise and air pollution are all results of urbanization’s rapid acceleration and growth in the number of cars. These problems have significantly negatively influenced urban traffic’s transport capacity and operational effectiveness. Cities have begun to actively develop ITSs actively in response to these conditions
[31,32][31][32].
2.3. Electric Vehicles
Due to their potential to lower greenhouse gas emissions and reliance on fossil fuels, electric vehicles (EVs) are a growingly well-liked form of transportation that has recently attracted much attention. Instead of using petrol or diesel fuel, an electric vehicle is propelled by an electric motor that draws power from rechargeable batteries. Three times as many electric vehicle (EV) users are anticipated by 2030 compared with 2011. This results from high-tech advancements in battery performance and how they affect vehicle autonomy
[34].
The environmental effect of electric cars is one of their main benefits. While the sales of electric vehicles have been increasing in both China and the US, it is essential to note that these countries also have many traditional fossil-fuel-powered vehicles on the road. Additionally, the growth in energy demand in these countries has led to increased coal use, the primary source of carbon dioxide emissions
[5,35][5][35].
Despite this, electric vehicles are still expected to significantly reduce carbon dioxide emissions in these countries in the long term. Unlike traditional cars, EVs don’t have tailpipe emissions. Even when the electricity they use is produced from fossil fuels, they still create less pollution than cars that run on gasoline. Because of this, EVs are a desirable alternative for those concerned about lowering their carbon impact. Electric cars come in various forms, such as battery electric vehicles (BEVs) and plug-in hybrid electric vehicles. (PHEVs). While PHEVs feature a battery and a conventional petrol or diesel engine, BEVs are powered by batteries. PHEVs can go a certain distance on electric power alone before the petrol engine takes over
[37][36]. Electric vehicles have advantages over conventional cars regarding cost-effectiveness and the environment. EVs might cost more up front, but they can save drivers money over time thanks to reduced fuel prices and less frequent maintenance needs. Since electric motors have fewer moving parts and require less maintenance, EVs also often have longer lifespans than conventional cars
[38][37]. Therefore, it’s a must to implement electric vehicles all over the world by reducing their adoption challenges.
In this regard, government incentives play a critical role in increasing the sales of electric vehicles by making them more affordable and accessible to the public
[17]. China is a prime example of this, as the government has implemented various policies and incentives to encourage the adoption of electric vehicles. These include financial incentives such as subsidies, tax breaks, and free license plates, as well as non-financial incentives such as preferential access to carpool lanes and free parking
[39,40,41][38][39][40]. These incentives have helped to reduce the upfront cost of electric vehicles, making them more competitive with traditional gasoline-powered cars. In addition, government investments in charging infrastructure and research and development have helped to address concerns around range anxiety and the technology’s reliability. These incentives have resulted in a surge in electric vehicle sales in China, making it the largest market for electric vehicles globally
[39,42][38][41].
It’s worth noting that these figures are constantly evolving as governments and private companies continue to invest in expanding their EV charging infrastructure. China has been particularly aggressive in building its charging network, intending to have 4.8 million charging points by 2025
[43][42]. Europe also invests heavily in expanding its charging infrastructure, with plans to have 1 million public charging points by 2025. The US is somewhat behind in the number of charging stations, but the Biden administration has proposed significant funding to help build the country’s EV charging network.
The classification and some of the advantages EVs offer over traditional vehicles are as follows:
2.3.1. Classification of Electric Vehicles
Vehicles that operate on electricity rather than petrol or diesel fuel are known as electric vehicles (EVs). There are several EV kinds, each with a unique engine and settings
[44][43]. According to their engine technology and settings, electric cars are categorized in the following manner in detail (
Figure 1):
Figure 1.
Classification of Electric Vehicles (EVs) according to engine technology and settings.
Battery Electric Vehicles (BEVs)
Battery Electric vehicles (BEVs): Rechargeable batteries are the only power source for BEVs, which are electric automobiles. They don’t have a backup generator or a petrol engine. Due to their lack of exhaust emissions, BEVs are regarded as the most ecologically beneficial form of electric car. However, they have a constrained driving range because the battery must be recharged
[45][44].
Hybrid Electric Vehicles (HEVs)
Hybrid Electric Vehicles (HEVs): HEVs are electric cars with petrol engines and electric motors. An electric motor propels the car at low speeds and during acceleration. The petrol engine takes over at higher speeds and when greater power is required. Because HEVs utilize regenerative braking to recharge their batteries, they do not require plugging in. Although they use less fuel than conventional petrol cars, they have some exhaust emissions
[45][44].
Plug in Hybrid Electric Vehicles (PHEVs)
Hybrid electric vehicles (HEVs) with bigger batteries that can be recharged by plugging a charging cable into an external electric power source in addition to internally by their on-board internal combustion engine-powered generator are called plug-in hybrid electric vehicles (PHEVs). They have a finite range of operations on electric power before switching to the petrol engine. PHEVs provide the ease of daily driving without a plug while allowing for electricity usage or on short journeys
[46][45].
Fuel cell electric vehicles (FCEVs)
Fuel cell electric vehicles (FCEVs): FCEVs react hydrogen gas with oxygen in the air to create power. They don’t have a battery, and their sole waste is water vapor. Although FCEVs can be refueled in a few minutes and have a greater driving range than BEVs, there is still a lack of hydrogen refueling infrastructure
[47][46].
Extended Range Electric Vehicles (ER-EVs)
Extended Range Electric Vehicles (ER-EVs) are a type of electric vehicle that combines the features of a Battery Electric Vehicle (BEV) and a Plug-in Hybrid Electric Vehicle (PHEV). ER-EVs have a larger battery pack than PHEVs, which allows them to travel longer distances on electric power alone. However, once the battery is depleted, a small gasoline engine generates electricity to power the electric motor and extend the vehicle’s range
[48][47].
ER-EVs are becoming more popular as they offer the benefits of both BEVs and PHEVs. They can be driven purely on electric power for shorter trips and travel long distances without stopping and recharging the battery. ER-EVs are also more environmentally friendly than traditional gasoline-powered vehicles as they produce fewer emissions.
One example of an ER-EV is the Chevrolet Volt, which has a battery range of approximately 53 miles before the gasoline engine kicks in. ER-EVs are a promising option for consumers looking for a more sustainable mode of transportation but needing the flexibility to travel longer distances.
Each type of EV has its advantages and disadvantages. BEVs and FCEVs produce no tailpipe emissions and are considered more environmentally friendly, but their limited range and lack of infrastructure may be a challenge for some users. HEVs and PHEVs offer more flexibility and do not require new infrastructure, but they still produce some emissions and are less environmentally friendly than BEVs and FCEVs
[48][47].
2.3.2. Benefits of Electric Vehicles
Environmental Benefits
Since EVs don’t emit tailpipe emissions, they don’t contribute to air pollution or greenhouse gas emissions. Even when fossil fuels are needed to generate energy to power the EV, it emits less pollution than a typical gas-powered vehicle
[37][36].
Lower Operating Costs
Compared with regular cars, EVs offer lower running costs. In general, electricity is less expensive than petrol or diesel, and as electric vehicles have fewer moving components, they require less maintenance. Due to electric motors’ excellent durability compared with internal combustion engines, they also often have longer lifespans
[37][36].
Energy Independence
Renewable energy sources, including solar or wind power, may power EVs. This lessens reliance on fossil fuels and may increase the sustainability of energy use
[37][36].
Efficiency
Compared with conventional cars, EVs are more efficient. The efficiency of the power plant will also affect the well-to-wheel (WTW) effectiveness. Compared with diesel cars, which vary from 26% to 38%, the overall WTW productivity of petrol vehicles ranges from 12% to 28%. In comparison, the WTW efficiency of EVs powered by natural gas power plants ranges from 14% to 30%, while EVs powered by renewable energy show an overall efficiency of up to 70%
[37][36].
Smooth and Quiet Operation
EVs operate significantly more quietly and smoothly than conventional cars because electric motors generate less vibration and noise. This may result in a more relaxing and pleasurable driving experience
[37][36].
Convenience
EVs may be charged at residences or public charging stations, so going to the petrol station is no longer necessary. Additionally, many EVs include capabilities that enable drivers to remotely warm up or cool the cabin, which may be helpful in extremely hot or cold weather
[37][36].
Performance
Electric motors can produce instant torque, allowing EVs to accelerate quickly. They could also have a lower center of gravity, making them more maneuverable and stable
[37][36].