Liz Parle can't drive. "I did try to learn," says the 24-year-old, Birmingham-born cafe owner, "but I failed my test a few times." Then she moved to London, where running a car can be a nightmare. Instead she cycles everywhere. "It's cheap, keeps me fit, and is of course better for the environment."

Parle is by no means atypical. In Britain, the percentage of 17- to 20-year-olds with driving licences fell from 48% in the early 1990s to 35% last year. The number of miles travelled by all forms of domestic transport, per capita per year, has flatlined for years. Meanwhile, road traffic figures for cars and taxis, having risen more or less every year since 1949, have continued to fall since 2007. Motoring groups put it down to oil prices and the economy. Others offer a more fundamental explanation: the golden age of motoring is over.

"The way we run cars is changing fast," says Tim Pollard, associate editor at CAR magazine, "Car manufacturers are worried that younger people in particular don't aspire to own cars like we used to in the 70s, 80s, or even the 90s. Designers commonly say that teenagers today aspire to own the latest smartphone more than a car. Even car enthusiasts realise we've reached a tipping point."

As hi-tech research and development budgets source to keep pace with the iPhone generation, Pollard says carmakers are also coming to terms with less possessive buyers. "Towards the end of the 20th century, manufacturers cottoned on to the fact that we were owning things for shorter periods."

This has led to a proliferation of different ownership and rental schemes such as Streetcar, Zipcar and Whipcar. In response, the latest deals from the big carmakers are very unlike your usual forecourt deal.

"Peugeot, for instance, has launched a European project called Mu," says Pollard. "You become a member and can then rent whichever Peugeot best suits your mobility needs that day. So you can borrow a van to move house at the weekend. Then get into a 308 for the school run, Monday to Friday. Then hop into an electric car to scoot silently around town. Then borrow a Peugeot bicycle to cycle to the pub in the evening. It's an attempt to second-guess how we'll run cars in future, and a pilot scheme at present, but you can do this today in London. Other car manufacturers are studying similar ideas."

Stefan Liske helps shape these ideas. The German entrepreneur once worked as a car designer and mechanical engineer, but now runs PCH, a company that models and plans new developments for companies entering choppy waters – their clients include Mini, Audi, Volkswagen and Daimler. Liske presents a picture of an industry that is being forced to confront major changes at every level: batteries that are so heavy the rest of the car must become lighter and use new materials; environmental pressures that mean current models, in which only 10% of a car is made from natural material, will be junked in favour of parts and interiors using "rattan, coconut wool, bamboo, recycled plastics".

The most radical change is that "in big societies, there is a huge status shift happening, where we are losing the idea that you use a car to define your status. So the industry needs more flexible leasing, financing and car-sharing models. And second, they have to find new revenue streams."

The near future that Liske describes echoes the computer industry's earlier shift from a business model based on hardware to one based on software. "Audi and Toyota have just invested $1bn in wind energy. If you're leasing a car from them, they can sell you the energy – or they go in a different direction like BMW, who just invested $100m in start-up companies offering transport-related mobile services."

Underpinning all these innovations and ideas is what Liske sees as a major behavioural shift among the generation of "digital natives". "They don't care about owning things. Possession is a burden, and a car is a big investment for most people – not just the vehicle, but the permits, the parking space."

He points to BMW, which in mid-July announced its investment in parkatmyhouse.com, a UK-based online parking marketplace that matches local drivers with homeowners who have empty garages and driveways. "Really," Liske says, "it was obvious a long time ago that something had to happen."

Crucially, these ideas aren't forming in the ether of maybe/if science fiction, but are based on proven technology that is ready to be rolled out.

"Cities such as London will, in 10 years, [have these vehicles] going along autonomously and you can hop in and out of them," he says.

A vehicle such as the one Liske describes is operating on the edge of the capital. The ULTra system consists of 21 electric vehicles running on a 4km elevated guideway from Heathrow's Terminal 5 to two stations in the business parking lot. It replaces shuttle buses, which still serve the airport's other parking lots. Passengers first boarded the ULTra pods in April, but was it officially launched last week. It's the first commercial Personal Rapid Transport (PRT) system anywhere in the world, and, as it drifts off from its bay in the terminal, it brings to mind both the Docklands Light Railway in London and Legoland's Sky Rider train.

"I think it's terrific," says David Metz, visiting professor in UCL's Centre for Transport Studies, as we glide to the parking bays. "It's obvious. Really, it should be here. Though the big question is what are the long-run costs and what is the feasibility of putting it on to other environments."

BAA, which helped develop the system and now owns a 70% stake in the company, says it cost £30m, which was spent over six years. While the ULTra cars themselves are simple – using the same tyres and wheels as a Ford Ka – the control-and-command system represents the most costly. This is housed in a single-storey building in the car park's compound and staffed by ex-Network Rail employees, erstwhile RAF air traffic controllers, as well as a mechanic from the Australian navy.

Though the operation is small, Mark Griffiths, its head, says it is ready for expansion at Heathrow; it is tendering for a project at the Golden Temple in Amritsar, India, and have had interest from the local councils in Bristol and Bath. So could a set-up like ULTra slip into an ancient spa town? "As long as there are planning regulations," says Griffiths. He outlines a number of scenarios that are currently within their reach: if, for example, a newly arrived passenger wanted to hire a car or book into a hotel, ULTra could present travellers with options on a touch screen, make reservations, and drive them straight into the lobby, where their room key will be waiting. "Zero emissions, you see."

Metz's account of underlying transport trends is simple: ultimately, we don't want to travel more. "Look at the [Department for Transport's] National Travel Survey, an annual poll of 20,000 people, dating back to the early 70s. The average travel time has not changed over that period. The number of journeys that people make in a year hasn't altered. It's about 1,000 journeys a year, and about an hour's travel per day."

This figure for daily travel is remarkably consistent. Look at Tanzanian villagers in 1986 or Britons today, and we all seem to travel, on average, for about 66 minutes a day. What did rise, in Britain at least from the 70s through to the 90s, was the distance people covered. "In the early 70s, it's about 4,500 miles per person per year, which includes all modes of travel except international travel by air, which is a different story," says Metz. "It rose to about 7,000 miles per year by the mid 1990s, and it stayed steady at about that level since."

Metz also thinks a general satisfaction with the number of places people can go has lead to this levelling-off; he calls this the saturation of demand.

"What is the benefit of travel?" he asks. "It's about getting more choices of places to go – the choice we have of jobs, doctors, hospitals, schools for our kids. My hypothesis is that the growth of daily travel has come to an end because now we have quite good choice."

Other analysts agree. "There are these models used by international agencies, and oil companies and the like," says Adam Millard-Ball, assistant professor at the department of geography of McGill University, Montreal. "They say as we get richer, we'll want to travel more. There's no limit. Our hunch was that this might not be the case."

Working with the late Lee Schipper, a senior research engineer at Stanford University, Millard-Ball examined travel figures dating back to the 70s, from as many industrialised countries as possible. "The data that we have shows fairly clearly that the growth in travel demand has stopped in every industrialised country that we looked at," he says. Schipper and Millard-Ball published their work last November in the paper Are We Reaching Peak Travel? Trends in Passenger Transport in Eight Industrialized Countries, adding to a growing body of work, all drawing similar conclusions. If these trends continue, it is possibly foresee a decline in car travel and a stagnation in total travel per capita.

Though he doesn't have any firm evidence to back it up, Millard-Ball thinks infrastructure plays a big part. "During the 70s and 80s we were building a lot more roads, allowing people to go further and faster. That era has come to an end, especially in Britain and America."

He also suggests that a general satisfaction with travel options also plays a role. "Once there's a set of places you can get to, it's less useful to get to any more. If there's a Sainsbury's two miles from your house, are you really going to go to the Sainsbury's four miles away?"

Break down the figures further, and other tendencies arise. Metz says the proportion of men in their 30s who drive has remained steady, while twentysomethings appear to be putting off getting behind the wheel until it's absolutely necessary. "It's partly the cost of ownership, the cost of insurance," he says. "Other factors that are more speculative are that there are more people in higher education, which typically takes place in urban centres where the car isn't part of the mix. Then people stay on in these urban centres."

He also says retirees often give up driving once they begin to suffer from minor disabilities.

"If you retire to a place with high population density, then mobility scooters come into their own." These electric vehicles haven't been thoroughly researched, and mass production hasn't quite brought automobile-industry standards. Yet he believes they could become a viable transport option for many people, even if they can only do 8mph, "and that's a bit fast for pavements".

Not everyone shares these rosy transport visions. Paul Watters, head of public affairs and roads policy for the AA, cautions against calling time on the car. "We are a small island with a very old road network, and a fairly complicated rail network. We haven't invested enough in transport for generations. People driving less is good for the environment, but not good for the economy, and we've got to find a way to make the economy keep going."

Though he is willing to admit that the AA might be "late to the party" on more progressive trends such as online car sharing or new hire schemes, Watters says car ownership still matters to its members. He also doubts whether major technological changes will make much difference within the next decade. "We might see bigger penetration of electric and hybrid cars, but it won't be a shattering change by 2020," he says.

He also cautions against abandoning the road network. "It's going to be very hard to maintain the road network over the next few years. As the economy picks up, we could see horrible growth in traffic and horrible congestion."

Neither the blue-sky visions of ULTra nor the jam tomorrow predictions of Watters are inevitable. Social trends can lead to change, but our travel habits are shaped by government policy too: by road, rail and airport building, most obviously, but also by planning regulations. Greenfield development, or the construction of housing on undeveloped land, is favoured by developers because it's cheaper to build and easier to sell. Yet this is often low-density, suburban-style housing that is poorly suited to public transport and more or less requires homeowners to drive. Brownfield building, though less profitable and less popular, often raises population density, making public transport more viable.

Metz is unimpressed by the new National Planning Policy Framework, which makes little reference to transport issues, while removing the national priority for brownfield development. There's nothing wrong with wanting a little house in the country, and a car to get you to and from it. Yet there is something reckless in restricting new buildings to a particular form of transport, especially if that form of transport shows signs of decline.

"There's this idea of a green metropolis, where land values are high so there's less space to heat, and where electric vehicles are viable, because the trips taken are shorter. If we're living in a world that is urbanising globally, this is worth considering."

It remains a compelling idea, though not everyone agrees its time has come. The car could be reaching the end of the road, or it could idle on for some time to come.

Additional reporting by Justin Quirk