NAE Perspectives offer practitioners, scholars, and policy leaders a platform to comment on developments and issues relating to engineering.
Chris Hendrickson (NAE) is director of the Traffic21 Institute at Carnegie Mellon University and chair of the National Academies’ Transportation Research Board Division Committee.
While transportation is costly in many ways and tiresome for many, it is critical for economic and social wellbeing. Goods and people need to reach their desired destinations in a timely manner.
Large amounts of money, energy, land, labor, time, and natural resources are devoted to travel. And it is associated with crashes, sprawl, and harmful air emissions. But travel can also be a romantic pleasure, as celebrated in numerous books and movies.
In the next few decades there are opportunities to reshape the landscape of familiar transportation systems. It is a pivotal time not seen for over a century, with transformations emerging in vehicle propulsion, automation, and telecommunications.
What’s Different Now
If a US citizen living in 1921 were magically transported 100 years into the future, he or she would be familiar with much of the current transportation infrastructure. In the 1920s cars, railroads, and planes were familiar. The technology has improved, but it has not been transformed. Vehicles still use internal combustion engines on roadways, with many pedestrian and vehicle conflicts. Public transportation performs much as it did a century ago. Roads have improved, especially for rural travel, but still look very much as they did a century ago (National Academies 2019). Container ships and jets would be novel to the visitor, but would certainly be recognizable as evolutions of 1921 steamers and biplanes. Many of the businesses dominating transportation and supply would also be recognizable, although with name changes, especially among petroleum and railroad companies.
In contrast to the past 100 years, the next few decades can transform transportation if we seize the opportunities available from new processes and technology. In this short piece, I outline some opportunities as well as some engineering and policy challenges. These opportunities could affect communities worldwide, so working in partnership with international companies will be beneficial. While I focus on opportunities, the challenges of maintaining, improving, and operating the existing transportation infrastructure and systems will remain (National Academies 2018, 2019).
Propulsion
Rather than relying on petroleum, transportation in the future should mainly use electricity for battery-electric or fuel cell vehicles, augmented by human-powered bicycling and walking (National Academies 2021). Battery-powered cars are already cost competitive in the marketplace, thanks to technology and manufacturing improvements in batteries. Similarly, battery-powered bikes, drones, and scooters are becoming widely available. Electric airplanes and boats are appearing.
Electric vehicles will be even more attractive if the large costs of air emissions are considered in purchase decisions, especially the costs of climate change due to greenhouse gas emissions. This transformative change in vehicle propulsion should be paired with net zero emissions for hydrogen production and power generation to avoid the enormous risks and costs associated with climate change.
There are a host of engineering challenges—and opportunities—in vehicle electrification, including building out affordable and accessible charging infrastructure, ensuring effective battery recycling, and long-term propulsion changes for railroads, ships, and airplanes. Electrification for long-range aircraft may not be feasible, so net zero emission liquid fuels may need to be developed. Research is needed to reduce the cost, improve the performance of batteries and fuel cells, and obtain or substitute for rare metals. Policy challenges also exist in enacting new emission standards, encouraging job creation, ensuring an equitable transition, spurring research, and mitigating the effects of a transition from petroleum.2Imageaddexpandmore-dots Title ImageSelect media Include in anchor check
Automation
Automation can be another revolutionary change for transportation. Improved safety is a major motivation for automation; reductions in driver costs, lower emissions, greater access for elderly and disadvantaged drivers, and improved roadway operations also provide benefits. Vehicle crashes result in enormous costs and roughly 40,000 US fatalities each year (National Academies 2018).
Partial automation in roadway vehicles is now widely available for collision warnings and active braking interventions, and this technology is already reducing the frequency and severity of collisions. Many motor vehicle manufacturers have made partial automation warning systems standard on their new vehicles. Airplanes, ships, and railroads have also implemented automated systems to supplement human operators. Driverless shuttles in applications such as airports are widely available. Highly automated vehicles are even providing limited driverless rides on public roadways in Phoenix, Arizona (Billeard 2021).