The convenience of driverless cars could encourage greater use of them, counteracting the technology’s energy savings and environmental benefits.
Autonomous technology allows vehicles to be more efficient during transport, which in turn reduces their energy consumption.
In a study from the University of Leeds, a number of factors were considered that achieve this and their energy savings were documented:
- More efficient computer-directed driving styles (0 to 20 per cent reduction in energy use).
- Improved traffic flow and reduced jams because of coordination between vehicles (0 to 4 per cent reduction).
- ‘Platooning’ of automated vehicles driving very close together to create aerodynamic savings (4 to 25 per cent reduction).
- Reduced crash risks mean that cars can be lighter and there is less emphasis from car buyers on high performance (5 to 23 per cent reduction).
However, the study also found that the greater appeal of self-driving technology could reduce or even outweigh the efficiency gains.
Lead researcher Dr Zia Wadud said: "There is no doubt that vehicle automation offers several efficiency benefits, but if you can work, relax and even hold a meeting in your car that changes how you use it.
“That, in turn, may change the transport equation and the energy and environmental impact of road transport."
The study uses analysis of self-driving technology combined with data on car and truck use, driver licenses, and vehicle running costs to model the impact on energy demand of various levels of automation on US roads by 2050.
It estimates that car energy consumption will actually increase between five and 60 per cent due to people choosing to use highly automated cars in situations where they would have previously taken alternative transport.
Dr Wadud said: "When you make a decision about transport, you don't just think about the out-of-pocket costs of the train ticket or the car's petrol; you also take into account non-financial costs.
"Car owners might choose to travel by train to relatively distant business meetings because the train allows them to work and relax.
“The need to drive is part of the cost of choosing the car, just as standing on a cold platform is part of the cost of the train. If you can relax in your car as it safely drives itself to a meeting in another city that changes the whole equation."
The study also predicts that people who currently find it difficult or impossible to drive, such as the elderly or some people with disabilities will have increased access to road transport with the advent of the new systems, resulting in an estimated two to 10 per cent increase in road energy use for personal travel.
Since Google revealed the first driverless car prototype in 2012, development on autonomous driving systems has accelerated rapidly.
The UK government recently allocated £20m to fund research projects looking to bring driverless transport to Britain’s roads.
In addition, the world’s first driverless public transport system came online last month with the launch of an autonomous six-seat shuttle bus in the Netherlands.