There is tremendous excitement in the transportation world about the idea of self-driving vehicles, also known as autonomous vehicles (AVs). AVs have the potential to transform our transportation system if their cost can be brought down to the point where they are affordable for the masses. The relevant policy question at this point is whether the potential benefits are large enough and likely enough to warrant investing substantial resources in researching this new technology. To answer this question, we also need to consider whether there is enough public benefit from such an investment as to necessitate putting tax dollars towards it. If not, we might conclude that the private sector can handle the research alone.

It can often feel like people will project whatever transportation future they might currently envision onto the capabilities of AVs. Those who care about reducing congestion, for example, see in AVs the potential for cars to drive closer together and increase roadway capacity. Those who care about land use see in AVs a way to reduce the need for parking in downtown areas. Those who care about the environment see AVs as a way to reduce fuel consumption and vehicle ownership.

AVs may indeed wind up making improvements in all of these areas. But technological innovations can often take longer than expected and have very different impacts than anticipated. Also, we sometimes fail to see the technologies that will wind up having the greatest impact. A look back at some of the technological changes in transportation that have – and have not – materialized over the last few decades offers some interesting lessons that we should heed as we consider AVs and next steps. These lessons could inform the strategies and policies we pursue with respect to AVs.

1. Technological change often takes longer than we expect.

A recent RAND report on AVs made this point very well by noting that air bags were invented in the 1950s—initially introduced in more expensive vehicles in the early 1970s—but did not become common until decades later, and were not actually made mandatory until 1999. In the case of air bags there were a number of reasons for this delay, including changing public attitudes (discussed below) and liability concerns. These issues are likely to be prevalent with AVs and could pose similar delays.

But perhaps the most important factor that inhibits technological change is cost. It is not the invention of the technology but getting the cost down that actually enables implementation. For example, we have the technological capability to fly passengers faster than the speed of sound. But we do not do it for civilians, and ultimately the Concorde program failed because the cost remains prohibitive. AVs could face a similar fate and will not achieve most of the benefits we hope for without substantial changes in cost. In our recent report on AVs, we estimated that the cost of these vehicles is likely to be at least $10,000 more than conventional vehicles for at least 10 years. Substantial research efforts will likely be needed in order to bring these costs down.

2. When looking at one potential change, we may miss another.

Much of what is being discussed right now with respect to AVs is wild speculation, because we never really know how people will adapt to or incorporate new technology until it arrives. Consider how people thought the Internet might change transportation, as opposed to how it has actually changed transportation. One of the most prominent concepts surrounding the coming of the Internet was that demand for travel would be reduced. The idea was that telecommuting and telework could replace a substantial amount of travel.

While this certainly happened to some degree, it was not the greatest impact of improved communications on transportation. Some of the larger impacts include the fact that the Internet has essentially eliminated the need for travel agents and provided complete transparency for airfares. The Internet has also enabled virtually perfect information regarding real-time traffic, driving, walking, bicycling and transit directions. The smartphone has brought us real-time technologies that allow ridesharing, on-demand livery services, and tell us when the next bus will arrive. All of these impacts were not necessarily obvious to foresee, and they have just begun to change transportation. The same may be true when we look at AVs today.

3. Societal expectations can change faster than technology.

Expectations for what levels of service and safety are acceptable today are far different than what they were decades years ago, because we keep making improvements and progress. For example, in the 1970s our expectations for public transit were low because it was primarily seen as a mode of last resort that was deteriorating beyond repair. Now mass transit is seen as the mode of choice in the largest cities and customers expect it to be clean, safe, and efficient. Similarly, major accidents for U.S. aircraft with significant loss of life used to be a more regular occurrence; now if there is a plane crash anywhere in the world it is a rarity and a major news story. Expectations change as things improve.

The same thing is likely to happen with AVs. While right now it seems like an exciting futuristic technology that would transform our lives, by the time it is affordable it is entirely possible that standards will have changed. For example, if smartphone and GPS technology enable new transportation systems that allow us to go everywhere we want whenever we want at a low cost without concern for parking, AVs would not make as much of a difference in that experience. If drunk and distracted driving is virtually eliminated through better enforcement and zero-accident policies, AVs may not have the dramatic impact on safety we are predicting at the moment. This does not mean we should ignore the potential benefits of AVs, but we should also recognize that they might naturally dissipate in scale over time.

Conclusions

From available evidence today, it would appear that there are more than enough public benefits that could arise from AVs so as to make government research investment worthwhile. Numerous research papers have demonstrated the potential value of this technology. But in order to make the case for government funding, it may be worthwhile for the research community to focus on the benefits that are most likely to come to fruition in the shortest timeframe.

Viewed from this perspective, perhaps the focus for AVs and their associated technological improvements should be almost exclusively on their safety potential. Many of the new safety technologies and benefits associated with AVs can be implemented and realized quickly, and demonstrate real value, even before we get to fully autonomous vehicles. Focusing on the safety benefits will create a positive message surrounding the technology around a goal that is almost universally shared, and safety is less likely to change as a goal for transportation improvements compared to other potential benefits. If we focus on safety, and bringing about safety benefits from technological improvements to vehicles that may eventually result in full automation, we are more likely to secure adequate research funding and maximize the benefits from these technologies more rapidly.

The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of The Eno Center for Transportation.