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Modelling the interaction between the energy system and road freight in Norway
Get PDFPublished by Elsevier Ltd. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/).By soft-linking models for transport demand, vehicle turnover and energy generation and use, we show how such models can complement each other and become more relevant and reliable policy support tools. A freight demand model is used to project commodity flows onto the 2050 horizon. An energy system model is used to map the relationships between energy prices, fiscal incentives, and optimal vehicle technologies. A stock-flow vehicle fleet model is used to calculate the time lag between innovation affecting new vehicles and the penetration of novel technology into the fleet. By running the latter two models in an iterative loop, we predict the flow of new vehicles with more or less decarbonized powertrains, contingent upon energy prices and fiscal incentives, while also obtaining a well-founded and more realistic assessment of the time needed for radical CO2 mitigation. The methodology is illustrated through a scenario developed for Norway.Modelling the interaction between the energy system and road freight in NorwaypublishedVersio
The effect of neighbourhood and urban center structures on active travel in small cities
No full textPublished by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)Densification is the key intervention strategy proposed in the urban sustainability planning literature. Nevertheless, the blueprint for action is still vague, and especially so in small cities. Is, for example, the premise for and reward of densification relatively transferable between city scales? In addition, does difference in centre structures and distribution of facilities in small cities have an implication for active travel? By focusing on three Norwegian small cities, this paper addresses how built environment and attitudes influence active travel behaviour in small cities with different centre structures. Using descriptive statistics, ANOVA test and negative binomial regression on survey data, the paper finds that attitude towards active travel as well as accessibility significantly influence walk/bike trip frequency. Moreover, variation in small-city centre structure has an important implication for active travel but the effect varies between facility types.The effect of neighbourhood and urban center structures on active travel in small citiespublishedVersio
Value of travel time by road type
Get PDFFlügel, S., Halse, A.H., Hartveit, K.J.L. et al. Value of travel time by road type. Eur. Transp. Res. Rev. 14, 35 (2022). https://doi.org/10.1186/s12544-022-00554-1Travel time is less costly if it is comfortable or can be used productively. One could hence argue that the value of travel time (VTT) of car travellers in economic appraisal should be differentiated by road type, reflecting differences in road quality. We explain the theoretical foundation for such a differentiation, review the relevant literature and show the results of an empirical case study based on actual route choice of highway drivers in Norway. We find little existing literature discussing the link between road type and VTT, but closely related findings suggest that that the impact on VTT could be substantial. Our empirical case study also suggests that the VTT is lower on higher quality road types. Applying this to economic appraisal would imply higher user benefits of road projects that improve road quality.publishedVersio
How Can Authorities Support Distributed Improvisation During Major Crises? A Study of Decision Bottlenecks Arising During Local COVID-19 Vaccine Roll-Out
Get PDFDespite the increased importance attributed to distributed improvisation in major crises, few studies investigate how central authorities can promote a harmonic, coordinated national response while allowing for distributed autonomy and improvisation. One idea implicit in the literature is that central authorities could help track and tackle common decision bottlenecks as they emerge across “improvising” local authorities as a result of shared, dynamic external constraints. To explore this idea we map central functions needed to roll-out vaccines to local populations and identify and classify bottlenecks to decision-making by local authorities managing COVID-19 vaccine roll-out in Norway. We found five bottlenecks which emerged as vaccine roll-out progressed, three of which could feasibly have been addressed by changing the local authorities’ external constraints as the crisis developed. While the national crisis response strategy clearly allowed for distributed improvisation, our overall findings suggest that there is potential for central authorities to address external constraints in order to ease common bottlenecks as they emerge across local authorities responding to the crisis. More research is to explore alternative centralized response strategies and assess how well they effectively balance centralized and distributed control. The study contributes to the growing literature examining the interaction between local and centralized response in crisis management.publishedVersio
The geography of public transport competitiveness in thirteen medium sized cities
Get PDFThank you for publishing your article with SAGE Publishing and Environment and Planning B: Urban Analytics and City Science. Your article “The geography of public transport competitiveness in thirteen medium sized cities” is now published.Securing sufficient accessibility with public transport is essential for reducing private car commuting. While most studies of transport accessibility are based on travel times, other quality factors such as the perceived disadvantage of congestion and service frequency are also of importance for transport mode choice. In this study, we use generalized journey times to calculate accessibility and public transport competitiveness, allowing us to account for other characteristics of commute trips than just travel time. We use detailed trip data to calculate generalized journey times to typical employment areas in thirteen urban regions in Norway. The results show that public transport services compete better with the car in the largest cities. Specifically, public transport is competitive for access to central employment areas but less so for less central employment areas. In the smaller cities, the private car is the most competitive mode on most commute trips. With detailed travel data, the method developed in this study can be replicated in other contexts to provide a more holistic measure of accessibility than traditional methods.The geography of public transport competitiveness in thirteen medium sized citiesacceptedVersio
Effects on accidents of police checks of drivers of heavy goods vehicles in Norway
Get PDFRune Elvik, Live Tanum Pasnin, Tor-Olav Nævestad, Effects on accidents of police checks of drivers of heavy goods vehicles in Norway, Transportation Research Interdisciplinary Perspectives, Volume 14, 2022, 100606, ISSN 2590-1982, https://doi.org/10.1016/j.trip.2022.100606 (https://www.sciencedirect.com/science/article/pii/S2590198222000689)During the period from 2007 to 2019, the number of drivers of heavy goods vehicles checked by the traffic police in Norway varied substantially. It declined during the first years of the period, then increased. This paper studies where there is an association between these variations and annual changes in the number of accidents involving heavy goods vehicles. A negative relationship is found: the more drivers checked, the fewer accidents. The relationship can be described by means of a dose–response function. The function indicates that when the number of drivers checked by the police is reduced by 50%, one may expect the number of accidents involving heavy goods vehicles to increase by 7.5%. A 50% increase in the number of drivers checked will be associated with a 3.5% reduction in the number of accidents, and a 150% increase in the number of drivers checked will be associated with an 8.6% reduction in the number of accidents.Effects on accidents of police checks of drivers of heavy goods vehicles in NorwaypublishedVersio
Factors Affecting e-Scooter Mode Substitution
Get PDFWhat transport modes do e-scooters replace? This article analyses the results from a web survey conducted among customers who were registered with five different shared e-scooter apps in Norway in October-November 2021. It is found that the context of the e-scooter trip, as well as characteristics of the users and their choice situation, impact the answer to that question. In all circumstances but for night rides, e-scooters most often replace walking. However, e-scooters are also found to replace cars as a transport mode, especially with longer e-scooter trips, if the user is male, if the e-scooter is privately owned (as opposed to shared), and to destinations that are poorly served by public transport.publishedVersio
Pandemic impacts on public transport safety and stress perceptions in Nordic cities
No full textPublished by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).COVID-19 has brought severe disruption and demand suppression to mobility, especially to public transport (PT). A key challenge now is to restore trust that PT is safe again. This paper investigates pandemic impacts on PT safety and stress perceptions in three Nordic cities, drawing on 2018 and 2020 survey data analysed in structural equation models. While finding modest pandemic effects on safety and stress perceptions overall, strong heterogeneities exist across gender, age and geographic categories. Women perceive less PT safety and more stress, especially during the pandemic. Older adults reduced PT more during the pandemic and perceived no stress reduction like younger adults. Stockholm travellers feel less safe and more stressed than in Oslo and Bergen, whilst pandemic PT use and perceived safety reductions are least in Bergen. The paper discusses the long-term implications for theory and policy across multiple mobility scenarios accounting for modal change and travel demand uncertainties.Pandemic impacts on public transport safety and stress perceptions in Nordic citiesKilde: Norges forskningsråd, Referanse: 316126publishedVersio
Do we know why the number of traffic fatalities is declining? If not, can we find out?
Get PDFElvik, R., & Høye, A. (2022). Do we know why the number of traffic fatalities is declining? If not, can we find out? Traffic Safety Research, 2, 000007. https://doi.org/10.55329/oyhu8693The number of traffic fatalities has declined by 80-90 % from the all-time peak number in many highly motorized countries. It would be of great interest to identify factors that explain this decline. Unfortunately, this is difficult, and an ideal method does not exist. This paper discusses some less-than-ideal methods. Multivariate statistical analyses are unlikely to be informative because they are likely to be affected by both multicollinearity and omitted variable bias. This implies that they will always include both too many and too few predictor variables, a problem that is impossible to solve. Historical reconstruction is another possible method. It explains fatality reductions over time byknown factors that are related to fatalities and for which sufficient information about their presence or uptake is available. Studies based on historical reconstructions show consistently that safer road user behaviouris a major contributor to reducing fatalities, followed by infrastructure and vehicle related safety measures. However, there is no way of establishing causality. The relative importance of different types of factors is highly dependent on the amount of information available. In a strict sense, there is therefore no prospect of providing a scientific explanation of the decline in traffic fatalities. In a less strict sense, historical reconstructions still may give an impression of relative contributions of some known factors. For example, the most recent Norwegian study identified factors that may explain more than half of the reduction of road traffic fatalities after 2000.publishedVersio
Modal accessibility disparities and transport poverty in the Oslo region
No full textErik Bjørnson Lunke, Modal accessibility disparities and transport poverty in the Oslo region, Transportation Research Part D: Transport and Environment, Volume 103, 2022, 103171, ISSN 1361-9209, https://doi.org/10.1016/j.trd.2022.103171 (https://www.sciencedirect.com/science/article/pii/S1361920922000037)Sufficient accessibility to opportunities, with different transport modes, is an important factor in order to avoid transport-related social exclusion and transport poverty. This paper investigates the social and geographical disparities in accessibility and time competitiveness of public transport in the Oslo region. Both place-based access to employment opportunities and the working population’s individual-specific commutes are measured. The study combines registry data with detailed accessibility metrics and uses descriptive maps and spatial regression models to study transport poverty. The results show that less affluent neighbourhoods suffer from low accessibility and poor time competitiveness of public transport, which is partly related to the suburbanization of poverty. This suggests that the transition to low emission mobility, with restrictions on car use, may be especially burdensome in less affluent neighbourhoods. The findings can help policy makers in securing an equitable transition from car to more sustainable transport modes.publishedVersio