What is the future of urban mobility? By 2050 there could be 2.5bn cars roaming the planet and most of them will be concentrated in cities, the OECD has reported. Saudi Arabia, one of the world's top oil exporters, expects domestic consumption to exceed exports by that year purely to feed its internal needs for automotive fuel. Meanwhile, if Chinese levels of automobile ownership reach US levels (840 cars per 1,000 people), demand for oil in China alone will surpass present-day global oil production, management consultants McKinsey have reported. And climate scientists predict irreversible environmental damage with continued carbon emissions if we follow this "business as usual" attitude. But, we no longer need to rely on predictions to understand the magnitude of this future, we can simply need to visit Beijing to realise that, as science fiction author William Gibson said, "the future is already here – it's just not very evenly distributed".
Beijing, a city with more than 20 million people, typifies the type of rapid urban densification the world is experiencing, particularly in the developing world. Plans by the Chinese government, reported by the New York Times, call for the movement of 250 million rural farmers into cities over the next 12-15 years. This shift from an agrarian society to an urbanised one has caused the cities to swell to the point where daily commutes are up to two hours for every resident. In January of this year, the particulate matter (PM) levels in Beijing, a measure of air pollution, exceeded 2.5 million, similar to one of the US's worst wildfires. Nearly a quarter of these toxic fumes can be directly attributed to carbon emissions from transportation. Yet, despite these unbearable conditions the allure of the private automobile is still captivating, aspirational, and a symbol of status.
There are four remedies to combat this polluting chaos. One approach is the electrification of the automobile. Another is vehicle sharing. Third is the creation of self-drive vehicles. And the fourth is increased usage of low-energy transportation options like walking, bicycling, and use of mass transit. Each approach adopts different strategies for solving the problem.
Electric vehicles (EVs) are primarily an auto-centric, engineering approach to the problem, whereby automakers have substituted the internal combustion engine with battery powered electric motors. This dramatically increases the fuel economy of the vehicle and eliminates tailpipe emissions. The rise of Tesla Motors and their commitment to create luxury electric sports cars has created positive momentum for EVs. Now nearly every major automaker in the world has an EV in the production pipeline. The development of new Lithium-ion battery technologies with much higher energy and power density has also made EVs more competitive. Eventually, EVs will be designed specifically around new electric drivetrains such as in-wheel electric hub motors, which eliminate the need for transmissions and gearboxes, further improving both driving and environmental performance.
The world's largest car sharing program, Zipcar, based in Cambridge, near Boston, has taken a business-model approach, allowing users to rent vehicles by the hour. Users have the benefit of access to mobility whenever they need it, without the burdens of car ownership such as car depreciation, parking, insurance, tolls, and maintenance. This is only the start. In 2012, the Transportation Sustainability Research Center at UC Berkeley reported an estimated 1.7 million car-sharing members existed in 27 countries. Car sharing has obvious benefits to the city. Zipcar estimates every shared vehicle replaces up to 20 private automobiles, thus reducing total vehicle miles and land devoted to parking. Even carmakers – such as BMW, Daimler and Ford - are getting into the action with their own programmes.
Autonomous automobiles are no longer science fiction, thanks to the initial funding efforts by the US government's Defense Advanced Research Projects Agency (Darpa). Tests have shown that the concept will work on real-life roads. The Urban Challenge in 2007 shifted the focus of this research to the complexities of city driving. Six teams out of 11 semifinalists finished that race, therefore validating the technology. Since then, automakers such as GM, Audi, Toyota, and others have invested the concept. The Google Driverless Car has already logged 300,000 miles on California roads without a human driver. After lobbying by Google, the states of California, Nevada, and Florida now allow driverless cars.