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Caulfield Brian

Brian Caulfield

Professor in transportation and Head of Department at Trinity College Dublin, Expert to the National Transport Authorithy (Ireland)
Professor Caulfield is Head of Discipline in the Department of Civil, Structural and Environmental Engineering. His research addresses global issues such as the environmental impacts of transport and methods to reduce the carbon impacts of transport.
Professor Caulfield has published over 200 papers in international journals and conferences. He currently has 9 PhD students and 6 postdoctoral researchers in his research group.
He is a Senior Editor of Renewable & Sustainable Energy Reviews and an Editor of Transport Policy. He is a member of the International Editorial Board of Transportation Research Part D: Transport and Environment, Case Studies on Transport Policy, the Journal of Cycling and Micro-mobility Research, and the Journal of Transport Geography.

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Decarbonizing mobility: where do we start?

Private electric vehicles are insufficient to decarbonize mobility. Although they yield environmental benefits, they come with several constraints and issues, including lithium extraction, which raises ethical concerns. They are also unable to tackle urban issues such as road congestion or bus delays.


When it comes to electrification, we should use our scarce resources to optimize shared fleets, rather than individual cars. For example, we’ve conducted research that suggested that the electrification of taxi fleets can help reduce emissions - and therefore become a viable alternative to cars.


The role that public transit plays in decarbonizing mobility cannot be understated. By its very nature, public transportation is more efficient than individual electric cars. Public transportation systems have started to integrate electrification across all modes: electric buses, hydrogen buses, electric rail… Ultimately, the key to fully decarbonizing this sector is figuring out how to get more people onboard.


Should cars be banned from cities?

I believe that, in tomorrow’s world, cars will have retreated from our cities. Concerned about air pollution and the rising costs of car ownership, the younger generation will catalyze this change.


To push cars out of cities, we will require more public transportation services. In places with advanced metro systems, there’s only so much tunneling you can do without addressing transportation needs above ground, such as buses or trams.


Private vehicles will certainly continue to pervade rural life; and that's where shared electric autonomous vehicles can play a role. Although driverless vehicles have become a hot topic, I believe that we should focus more on ride-sharing rather than autonomous technology.

The future of mobility doesn’t — and shouldn’t — depend on futuristic tech solutions such as flying cars. Although technology will play a part in changing the way we move in cities, it’s only part of the bigger picture. As we tend to emphasize and amplify the benefits of new car technologies, I believe that our main focus should be on improving our already-existing basic services. We must channel our energy into enhancing our public transit networks to make them safer and more reliable.


Considering the finite spaces in cities, coupled with the effects of climate change, we will need more urban areas that can cool people down. As our cities and populations continue to grow, space will become a premium. Our main challenge is not the lack of public transportation;, but rather the lack of space.


Once we phase out cars and optimize our transportation networks, we will be able to redesign our cities with cleaner, healthier air. Cities where our children and grandchildren will wonder why we ever drove polluting cars in the first place.

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