Jaime Suarez

Road transport accounts for the largest share of EU transport-related greenhouse gas (GHG) emissions, and its decarbonisation increasingly relies on the electrification of the light-duty vehicle (LDV) fleet. However, most environmental assessments still rely on type-approval consumption values and coarse vehicle categories, overlooking both real-world performance and the heterogeneity of the passenger-car fleet. This study presents a comprehensive, extended Well-to-Wheel (WtW) assessment of the European Economic Area’s newly registered LDV fleet in 2023, covering ca. 11.3 million vehicles. The approach integrates three elements: (i) a detailed vehicle classification distinguishing standard cars, sport utility vehicles (SUVs), multipurpose vehicles (MPVs), and vans by powertrain, fuel type and size; (ii) real-world energy and fuel consumption factors derived from On-Board Fuel and Energy Consumption Monitoring (OBFCM) data covering about 8 million vehicles, complemented by dedicated battery electric vehicle (BEV) driving campaigns; and (iii) an extended WtW methodology that integrates upstream (Well-to-Tank) and tailpipe (Tank-to-Wheel) emissions with vehicle production impacts. Results show that climate change impacts decrease consistently with the degree of electrification, with BEVs achieving approximately 50% lower impact than internal combustion engine vehicles (ICEVs), despite production-phase emissions accounting for up to half of their total footprint. Vehicle size strongly influences both energy consumption and emissions, with electricity consumption in large BEV SUVs up to twice that of compact models. These findings underline the importance of jointly considering real-world operation, vehicle categorisation and production-related impacts when assessing decarbonisation pathways, offering policy-relevant insight into the evolving climate performance of the EU passenger vehicle fleet.

The driving style is a crucial variable for real-world vehicle energy performance. This study uses a state-of-the-art methodology to separately assess its impact on the energy consumption. A benchmark driving cycle is modified according to specific driving styles, and the corresponding energy consumption is theoretically simulated. The driving style characterisation includes acceleration, braking and gear-shifting patterns for each driver through ad-hoc metrics. The methodology establishes a comparative analysis regarding the energy impact of a pool of drivers. Furthermore, the variability of a driver’s consumption on different vehicle technologies is assessed by considering an internal combustion engine- (ICE) vehicle and a plug-in hybrid electric vehicle (PHEV). The results reveal that each driver exhibits characteristic and heterogeneous acceleration and braking styles, with the gear-shifting style playing a significant role in the vehicle’s fuel consumption. From a policy perspective, this work contributes in the understanding of the discrepancies in energy consumption between officially reported values and the real-world performance.

The transportation landscape is witnessing profound changes due to technological advancements, necessitating proactive policy responses to harness innovation and avert urban mobility disruption. The sharing economy has already transformed ridesharing, bicycle-sharing, and electric scooters, with shared autonomous vehicles (SAVs) poised to reshape car ownership. This study pursues two objectives: firstly, to establish a market segmentation for shared ride services and secondly, to evaluate the environmental impact of ridesharing in different contexts. To mitigate potential biases linked to stated preference data, we analysed the navette service, utilized by a research institute in Europe, closely resembling future SAVs. The market segmentation relied on hierarchical cluster analysis using employee survey responses, while the environmental analysis was grounded in the 2019 navette service data. Our analysis revealed four unique employee clusters: Cluster 1, emphasizing active transportation and environmental awareness; Cluster 2, showing openness towards SAVs given reliable alternatives are available; Cluster 3, the largest segment, highlighting a demand for policy support and superior service quality; and Cluster 4, which places a premium on time, suggesting a potential need for strategies to make the service more efficient and, consequently, discourage private car use. These findings highlight a general willingness to adopt shared transport modes, signalling a promising transition to shared vehicle ownership with significant environmental benefits achievable through service design and policy measures.

We have investigated the dissociation of a resonant state that can be formed in low energy electron scattering from H₂O⁺. We have chosen the second triplet resonance above the state of H₂O⁺ whose autoionization mainly produces H₂O⁺ ( ). We have considered both dissociation of the resonant state itself, dissociative recombination (DR), or the dissociation of the H₂O⁺ cation after autodetachment, dissociative excitation (DE). The time‐evolution of a wave packet on the potential energy surfaces of the resonance and cationic states shows, for the initial conditions studied, that the probability for DR is about 38 % while the probability for DE is negligible.

He²⁺, Li³⁺and C³⁺collisions with H₂O are studied with three different classical and semiclassical methods, which agree for target net electron loss. The relevance of two- and three-electron removal in the fragmentation is shown.

The fragmentation of the water cation from its ²B₂ electronic state, allowing the participation of the ²B₁, Ã ²A₁ and ²B₁ states in the process, is simulated using the extended capabilities of the collocation GridTDSE code to account for the nonadiabatic propagation of wave packets in several potential energy surfaces connected by nonadiabatic couplings. Molecular data are calculated ab initio. Two initial wave packets are considered to reproduce two different experiments. The isotopic effect in the fragmentation of D₂O⁺ and HDO⁺ is also studied and the results show very good agreement with the experimental cleavage preference in the fragmentation of HDO⁺.