Driverless cars as a service, batteries and urban spaces…

Professor Mark Barry shares ideas on how the role of the car may change over the next 20 years


Having been involved in the South Wales Metro since 2011, I’d like to share some ideas that I think will be relevant in how the role of the car may change over the next 20 years. A future that will result from the interplay of developments in both technology and culture.


Let me start with an obvious but overlooked observation.  If you look out of most windows what do you see?  Tens, hundreds, of cars sitting there not being used, or if they are, stuck in traffic.  Most cars spend probably 95% of “their lives” doing absolutely nothing.  This clogs up streets and ties up natural resources.  Having to design our cities around what cars do when they are not moving is as bad as having to do so when they are. We have also become desensitised to the nearly 5 deaths on average each day (1700 per year!) on the UK’s roads; there are also air quality and health impacts that are only now being fully appreciated leading to even more deaths.


Cars will become more fuel efficient, safer, cleaner and will undergo profound changes as a result of electric traction and autonomous “driverless” control.  However, when imagining the future, we too often extrapolate from where we are today, which is not always the best starting point.  For example, there is talk of future roads being filled with thousands of “driverless” vehicles running nose to tail creating a high-speed mass transit system.  However, such a system will have as many potential failure points as there are vehicles; this is not practical or safe. Nor does it does address the issue of congestion to design a mass transportation system around units that carry only 3 or 4 people.  Much better to have larger vehicles moving many more people thus reducing the collective risks and using the available road space more efficiently.   On that basis, high volume inter & intra-regional transport will still be most efficiently and safely delivered by trains, light rail and buses (or Elon’s hyperloop!).


Where autonomous cars could work is in urban areas where many people need to make many different, independent and shorter journeys at lower speeds; and where driving can be safer if the driver is removed.  Speeds can be regulated so that many failure points can be designed to have little or no impact on other road users – especially pedestrians and cyclists.  This is currently the domain of the personal car, local bus and taxi. However, the emergence of cleaner, safer, driverless vehicles with the potential for lower unit operational costs will change all that.  


In parallel with the emergence of autonomous vehicles, innovation is also accelerating in traction power.  Many are calling for electric charging points at homes, places of work, etc, to support the “electrification” of the current car paradigm.  Well I think that paradigm is changing and in terms of physics it is not very efficient to charge millions of vehicles from millions of domestic 240V charge points (can the grid cope and what might the transmission losses be?).  The biggest constraint on a more efficient charging methodology is the time it takes to charge, the energy losses in doing so as well as the cost and size/composition of batteries.  I suspect that once battery/fuel cell technology becomes more developed, systemised and affordable then we won’t need to charge in the same way.  Rather than petrol stations we could have battery stations where “modular batteries” can be charged efficiently using high voltage 3 phase supply and swapped in/out of vehicles in a couple of minutes.  In fact, the emergence of modular “quick swap” batteries is already happening. Take a look at Sun Mobility,  a new venture from Chetan Maini in India; this is early stage but a signpost to a possible electric future.


However, this all assumes we will still use cars in the way we do today…but we won’t.  Today, many young people are more comfortable with even poor public transport, cycling or walking rather than owing a car. Rising costs (especially insurance) and competing demands for the diminishing incomes of young people will result in the personal car becoming relatively more unaffordable – and driving costs for young people looks set to continue increasing.  


Yes, some people will still own cars, but most won’t bother – cars will become part of an on demand, low cost service in most urban areas, with large fleets of autonomous vehicles (and probably government regulated) by organisations with scale, experience and capability in delivering public transport.  The biggest part of the current taxi fare, the driver, can be removed thus dramatically reducing the operating costs of the service. With such vehicles operating at much higher levels of utilisation as part of a managed fleet then further operating efficiencies can be secured. The cost to the end user will then be much lower than either a taxi or maintaining one’s own personal car.  This should sound alarm bells for anyone operating as a gig economy taxi driver or low demand route bus driver.


We will still have mass rapid transit (HR, LR & BRT) for major inter and intra urban travel corridors, but these more traditional public transport services will be augmented and integrated with the service provided by fleets of fuel efficient, low carbon, “driverless taxis” that will predominantly be used for short journeys (e.g. from home to local Metro stop, hospital, office, etc). This was highlighted in a report produced by the Association of German Transport Companies, ( in 2015. This is already beginning to happen; Deutsche Bahn are trialling autonomous vehicle as part of their wider public transport offering ; Renault and Nissan are also exploring such “fleets”.  


Consequently, there will be fewer cars, taxis and bus services freeing up road space.   Today’s car parks, which are full all day, will in future be full all night as fleets of cars are serviced and have their batteries replaced ready for the next day’s operations.  With the human factor removed from the fewer cars operating, roads will become safer for passengers, cyclists and pedestrians. This will enable innovation in how we design and develop our cities, streets and urban spaces; for example, the road/pavement divide may diminish in importance, we won’t need bike lanes as with fewer and safer cars, there will be more space on our current roads for cyclists.


Those that still want cars will continue to use them – people still buy vinyl records after all.  However, in future, aside from a personal carbon tax perhaps we should also tax cars, not for how much they are used, but, counter intuitively, for how little they are used. This would provide a disincentive for acquiring a vehicle (and the natural resources it uses) if you are not going to use it.  Because of the increased safety risks perhaps cars with “drivers” will be restricted from accessing many parts of our towns and cities.


So yes, there will still be cars – but far fewer than today and they will be less personal. Most of us will use cars as part of a wider public transport service to move around cities that can in future be designed around people.


22nd April 2017, postscript:  I just spent 6 hrs in A&E having been knocked off my bike earlier today by a car. An autonomous vehicle with comprehensive sensors and safety systems would have made todays incident far less likely!









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