• Energy Research
• 2021-2025close
• Transport Research close

The adoption of fully battery-powered electric vehicles (EVs) in Kuwait is currently at less than one percent of the population, and hence Kuwait has the lowest index rank among countries around the globe. Effectively, only Kuwaiti nationals have the opportunity to own EVs, as there are no fast direct-current charging stations in Kuwait, and Kuwaiti landlords (expats cannot own real estate) do not allow the installation of EV-charging home wall boxes at their rented properties. Given these facts, this paper only focuses on the preferences of Kuwaiti nationals, even though they only constitute 25 percent of the population of Kuwait. To accomplish the present objectives, a quantitative descriptive method (closed-ended questions) was used to collect data from a sample of 227 Kuwaiti nationals who were representative of the owners of half a million internal combustion engine (ICE) cars and that were categorized as early majority consumers. The findings of the present study indicate that over 50 percent of the respondents would prefer to buy an EV in the following three years when certain criteria were satisfied, including government-controlled pricing policies and recharging point availability, high-speed roads, and free EV-dedicated parking spaces. Furthermore, over 40 percent of respondents stated that they would contemplate purchasing an electric vehicle if the price of gasoline or diesel increased by 19 to 50 percent. The findings also indicated that more than 40 percent of respondents believed that EVs are fire- and crash-safe, and roughly 50 percent of the respondents would be willing to pay between 6 and 20% more for an EV because they believe that EVs are ecofriendlier vehicles and are significantly faster than conventional petrol vehicles. Additionally, respondents rewarded those vehicles with an excellent mark because of their ecological, economical, and technological attributes and benefits.

Plug-in electric vehicles (PEVs) have immense potential for reducing greenhouse gas emissions and dependence on fossil fuels, and for smart grid applications. Although a great deal of research is focused on technological limitations that affect PEV battery performance targets, a major and arguably equal concern is the constraint imposed by the finite availability of elements or resources used in the manufacture of PEV batteries. Availability of resources, such as lithium, for batteries is critical to the future of PEVs and is, therefore, a topic that needs attention. This study addresses the issues related to lithium availability and sustainability, particularly supply and demand related to PEVs and the impact on future PEV growth. In this paper, a detailed review of the research on lithium availability for PEV batteries is presented, key challenges are pinpointed and future impacts on PEV technology are outlined.

Noise emissions from transportation remain one of the greatest environmental issues of modern day. Inhabitants in urban environments are especially exposed, with almost 80 million people in the European Union exposed to noise levels exceeding the recommended limits set by the World Health Organization (WHO). While the health-related effects from exposure of traffic noise are problematic and of utmost importance to reduce, availability to efficient transport is also an essential necessity. These conflicting requirements on transportation calls for a more holistic approach to traffic analysis, and to understand the relation between these effects from the traffic. This work investigates properties of traffic, such as the exposure of noise emissions, the vehicle-specific energy demand and duration, to analyse the sustainability of transport. The traffic simulation software SUMO is used to provide a discrete traffic model with individual vehicles, combined with the European vehicle noise source model IMAGINE used to model discrete sound sources that allow for directivity in the sound field and is speed- as well as acceleration-dependent. The resulting cost related to the exposure of noise is then evaluated at several measurement points in the network using a willingness-to-pay (WTP) model. This allows for an analysis of the relation between noise exposure cost and energy efficiency through the estimation of the vehicle-specific energy demand. A time-varying traffic demand is added to analyse the effects of a varying traffic density and congestion to the relation between the different properties. Additionally, the concept of allocating the noise exposure cost down to individual vehicles by means of contributed acoustic energy is expanded to take the main contributing vehicles and time-segments into consideration, and to allow for a non-linear weighting factor. These allocation strategies also allow for a bias to assign a higher cost to noisier vehicles, as vehicles that contribute more to the overall noise exposure than others may be more easily identified. Lastly, the relation between the traffic properties are analysed by means of correlation. Initial studies indicate that the correlation is dependent on the traffic density and the amount of vehicle interaction. Trafikbuller är en av de största miljöproblemen idag. Invånare i stadsmiljöer är särskilt utsatta, där nära 80 miljoner personer i Europeiska Unionen är utsatta för bullernivåer som överskrider Världshälsoorganisationens (WHO) angivna gränsvärden. Medan de hälso-relaterade effekterna från exponering av buller är på en ohållbar nivå och bör reduceras, så är även tillgänglighet till effektiv transport en nödvändighet. Dessa motstridiga krav på transportnätverket kräver en mer holistisk syn på trafikanalys, för att förstå relationen mellan dessa effekter från trafiken. Detta arbete undersöker de effekter som uppstår från trafiken, såsom bullerexponering, det fordons-specifika energibehovet och tiden i trafiken, för att analysera hållbarhetsaspekter för transporter. I detta arbete används trafiksimuleringsprogrammet SUMO för att erhålla en diskret trafikmodell med individuella fordon, i kombination med den europeiska fordonsbullermodellen IMAGINE som används för att modellera diskreta bullerkällor som tar hänsyn till direktivitet i ljudfältet samt fart- och accelerationsberoende. Den resulterande kostnaden för bullerexponeringen beräknas därefter för ett stort antal mätpunkter i nätverket genom en modell för betalningsvilja (WTP). Detta tillåter en analys av förhållandet mellan kostnad från bullerexponering och energieffektivitet baserat på det fordonsspecifika energibehovet. Ett tidsvarierande trafikflöde läggs på för att analysera effekterna från en varierande trafiktäthet och trängsel på förhållandet mellan de olika egenskaperna. Dessutom expanderas konceptet att allokera den buller-relaterade kostnaden ner till enskilda fordon baserat på deras enskilda bullerbidrag. Detta för att potentiellt kunna allokera en större del av den totala kostnaden till fordon som bidrar särskilt mycket till den totala bullernivån eller till särskilda tidsegment med höga bullernivåer, samt att tillåta en ickelinjär viktfunktion. Dessa allokeringsstrategier ger också möjligheten att allokera en högre kostnad till bullriga fordon, då fordon som bidrar mer till den totala bullernivån kan lättare identifieras. Slutligen analyseras förhållandet mellan trafikegenskaperna utifrån korrelation. Inledande studier visar att korrelationen beror på trafiktätheten och mängden fordonsinteraktion i trafiken.

Current trends in the global climate facilitate the displacement of numerous marine species from their native distribution ranges to higher latitudes when facing warming conditions. In this work, we analyzed occurrences of a circumtropical reef fish, the spotfin burrfish, Chilomycterus reticulatus (Linnaeus, 1958), in the Madeira Archipelago (NE Atlantic) between 1898 and 2021. In addition to available data sources, we performed an online survey to assess the distribution and presence of this species in the Madeira Archipelago, along with other relevant information, such as size class and year of the first sighting. In total, 28 valid participants responded to the online survey, georeferencing 119 C. reticulatus sightings and confirming its presence in all archipelago islands. The invasiveness of the species was screened using the Aquatic Species Invasiveness Screening Kit. Five assessments rated the fish as being of medium risk of establishing a local population and becoming invasive. Current temperature trends might have facilitated multiple sightings of this thermophilic species in the Madeira Archipelago. The present study indicates an increase in C. reticulatus sightings in the region. This underlines the need for updated comprehensive information on species diversity and distribution to support informed management and decisions. The spread of yet another thermophilic species in Madeiran waters provides further evidence of an ongoing tropicalization, emphasizing the need for monitoring programs and the potential of citizen science in complementing such programs.

How can urban policies and planning approaches help in achieving a safer mobility and carbon reduction in the transport sector? The attention of planners and policy makers towards the promotion of sustainability and reduction of environmental impacts has grown in recent years. This paper investigates the role that Urban Planning plays in the long term towards a safer and climate friendlier mobility, highlighting the need for integrated approaches gathering spatial planning and mobility management. After a review of several urban policies and planning strategies, initiatives, and approaches, mainly based on the urban scale, the paper presents an urban regeneration case study leading to an increase of pedestrian accessibility at the neighborhood level. This can be seen as a support tool to foster sustainable, safe, and climate friendly mobility in cities. The results of the performed analysis show a dependency of accessibility from two different factors: the distribution of services and the capillarity of the soft mobility network, which can contribute to creating a more walkable space.

In electrified vehicle applications, understanding the battery characteristics is of great importance as it is the state-of-art principal energy source. The key battery parameters can be identified by one of the robust and nondestructive characterization techniques, such as electrochemical impedance spectroscopy (EIS). However, relaxing the battery cell before performing the EIS method is crucial for the characterization results to be standardized. In this study, the three most common and commercially available lithium-ion technologies (NMC/graphite, LFP/graphite, NCA/LTO) are investigated at 15–45 °C temperature, in the range of 20–80% state of charge (SoC) and in fresh and aged state of health (SoH) conditions. The analysis shows that the duration of the relaxation time before impedance measurement has an impact on the battery’s nonlinear behavior. A rest time of 2 h can be proposed, irrespective of battery health condition, considering neutral technology-based impedance measurement. An impedance growth in ohmic and charge transfer characteristics was found, due to aging, and the effect of rest periods was also analyzed from an electrochemical standpoint. This experimental data was fitted to develop an empirical model, which can predict the nonlinear dynamics of lithium technologies with a 4–8% relative error for longer rest time.

Route game is recognized as an effective method to alleviate Braess’ paradox, which generates a new traffic congestion since numerous vehicles obey the same guidance from the selfish route guidance (such as Google Maps). The conventional route games have symmetry since vehicles’ payoffs depend only on the selected route distribution but not who chose, which leads to the precise Nash equilibrium being able to be solved by constructing a special potential function. However, with the arrival of smart cities, the real-time of route schemes is more of a concerned of engineers than the absolute optimality in real traffic. It is not an easy task to re-construct the new potential functions of the route games due to the dynamic traffic conditions. In this paper, compared with the hard-solvable potential function-based precise method, a matched Q-learning algorithm is designed to generate the approximate Nash equilibrium of the classic route game for real-time traffic. An experimental study shows that the Nash equilibrium coefficients generated by the Q-learning-based approximate solving algorithm all converge to 1.00, and still have the required convergence in the different traffic parameters.

The increasing use of power electronic inverters in electrical drives is leading to the unexpected inception of partial discharges (PD) within the insulation system of electric machine stator windings. Unfortunately, the short rise and fall times of such voltages, below 100 nanoseconds in most cases, create high-magnitude conducted and radiated interferences that affect the measurements. Detecting partial discharges in these systems with inductive or electromagnetic sensors turns to be an important challenge, especially when interference and partial discharges share the same bandwidth. In this work, the authors propose a technique to detect the occurrence of PD in such systems, even when they are masked by disturbances. The proposed technique combines an analog high-pass filter stage and a digital band-pass to select a proper spectral interval. The resulting signal is converted to the base-band, where two metrics based on the peak-to-average power ratio are proposed. Experimental results obtained with the signals acquired with two antennas show that both proposed metrics exhibit a significant increase, about ten times greater, when the applied voltage exceeds the PD inception voltage. These contributions define new markers for the detection of PD events created by pulsed voltages with overlapped overshoots with promising results.