Tunnels can contribute significantly to the overall energy consumption and carbon emissions of a railway, both in terms of embodied energy and emissions (those associated with the materials and the construction process) and in terms of operational energy and emissions (due to the increased air resistance experienced by a train inside a tunnel). Although tunnels may be a necessary component of railway infrastructure, it is important that their impact on carbon emissions is fully understood, especially when comparing the railway with other modes. This paper reviews existing literature and uses a case study to develop understanding. Trade-offs between embodied and operational energy and emissions are explored.
Crowded trains are a feature of many railway networks, and adversely affect both train passengers and rail operators. For passengers, the lack of space or inability to get a seat can lead to a lack of physical comfort, reduced productivity and increased stress. Crowded trains can also lead to problems boarding and alighting, increasing dwell times and making it harder for operators to provide a reliable service. It is therefore desirable to reduce crowding levels, but it isn't always practical to achieve this by increasing capacity and other measures need to be considered. Some passengers have shown willingness to change their behavior to avoid crowding, for example by waiting for a later train, and measures to encourage such behavioral changes more widely could be beneficial overall. Better information provision could be one such measure, and a stated preference survey was undertaken on a commuter and airport service in order to investigate this further. It was found that the provision of information about crowding levels and seating availability on alternative trains would encourage some passengers to wait for a less crowded train. While the willingness of passengers to wait for a later train varied with both trip purpose and with the origin station, the findings suggest that real-time information would improve the passenger experience and could form the basis of a revenue neutral demandmanagement system. The implications for station design are particularly pertinent for countries such as the USA where significant investment in new passenger rail systems is expected.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.