Low-mobility: The future of transport Patrick Moriarty a, *, Damon Honnery b a Department of Mechanical Engineering, Monash University, P.O. Box 197, Caulfield East 3145, Vic., Australia b Department of Mechanical Engineering, Monash University, P.O. Box 31, 3800 Vic., Australia ARTICLE INFO Available online 22 July 2008 ABSTRACT Nearly all researchers into the future of global passenger transport assume that both car- ownership and overall vehicular travel will continue to rise. But they also increasingly acknowledge the environmental and resource problems facing vehicular transport, particularly global climate change and oil depletion. In order to meet these challenges, researchers propose a variety of technological solutions, including greatly improved vehicular fuel efficiency, alternative fuels and propulsion systems, and carbon capture and storage. In this paper we question whether these optimistic solutions can be developed and widely deployed in the limited time frame available, and argue instead that not only are ever-rising vehicular mobility levels unlikely to occur, but that the human costs of continuing this approach are also too great. Instead we argue that because transport is a derived demand, we must first articulate a preferred vision of the future, then design an appropriate, sustainable transport system. Finally, we briefly outline what such a low- mobility future transport system would look like, using our own city, Melbourne, Australia, as a case study. ß 2008 Elsevier Ltd. All rights reserved. 1. Introduction: forecasting global passenger travel Global passenger transport has risen steeply over the 20th century; in the year 2000, total vehicular travel worldwide was estimated as about 32 trillion passenger-km (tkm), up from only 2.8 tkm in 1950 [1,2]. Presently, most global passenger travel is by car, although air travel is increasing its share. Schafer and Victor [3] have projected global vehicular travel out to the year 2050. They consider travel to be constrained only by individual time expenditure and household budgetary outlays. They claim that, worldwide, travel time (including that for non-motorised travel) is roughly constant at about 1.1 h per person per day, and that at least for countries with levels of car ownership at 0.2 cars/capita and higher, households limit transport expenditures to around 10–15% of household income. With additional assumptions – chiefly on future global income growth – future travel levels and their split between high-speed (air and rapid rail) and other modes can be calculated. By 2050 they project a total of 103 tkm travel, with high-speed modes and car travel accounting for close to 80%. Although they see some bridging of the gap between high- and low-travel countries, travel is also projected to grow strongly even in the already high-mobility OECD countries. Other recent studies have also forecast greatly expanded vehicular travel for the 21st century. Ausubel and Marchetti [4] again project vehicular travel as growing strongly within travel time and income constraints, but regard underground magnetically levitated (maglev) trains running at very high speeds in evacuated tunnels as the major travel mode of the future. Unlike Schafer and Victor, they explicitly recognise the need to reduce transport greenhouse gas emissions. They regard ever-rising vehicular mobility as a fundamental human desire, rather than as a derived demand for access. The airline manufacturer Airbus [5] annually issues single value forecasts 20 years ahead for world air travel. Their latest projection Futures 40 (2008) 865–872 * Corresponding author. Tel.: +61 3 9903 2584; fax: +61 3 9903 2076. E-mail address: patrick.moriarty@eng.monash.edu.au (P. Moriarty). Contents lists available at ScienceDirect Futures journal homepage: www.elsevier.com/locate/futures 0016-3287/$ – see front matter ß 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.futures.2008.07.021