A plan to give "garden city" status to up to 40 English towns, including Exeter, has won a £250,000 prize.
New garden cities which would double the size Exeter and Taunton would help to ease Britain's housing shortage, a leading economist has suggested.
The Westcountry cities were among 40 identified for massive expansion by David Rudlin, an urban designer who scooped the Wolfson prize, the second-biggest economics prize after the Nobel.
His award-winning proposals, which earned him £250,000, included circular developments, with parks and allotments, of up to 150,000 people per town.
Mr Rudlin argued models pioneered in Scandinavia, the Netherlands and Germany should be adopted by Britain which could "take a confident bite out of the greenbelt".
He said up to 100,000 homes a year would be needed to be built on greenfield sites in order for the demand for six million new homes over the next 30 years to be met.
Mr Rudlin said garden cities, connected by trams to existing centres, allowed development "in a way that reduces its impact, maximises its potential for sustainability and reinforces an existing place".
"Expansion would take the form of town extensions connected to the city centre by a tram or bus rapid transit," he said, "with each extension consisting of green, walkable neighbourhoods with primary schools, business uses, and local shops".
He set out how 20% of new homes would be classed as affordable while some sites could be handed over to self-builders.
Other target areas included Cheltenham, Gloucester, Bath, Salisbury and Poole. He also proposed a "deal" to get opponents onside – dropping building in existing suburbs in favour of larger garden city extensions. Targets set by local authorities for tens of thousands of new homes across Devon and Cornwall by 2030 have become a major bone of contention.
The Campaign to Protect Rural England (CPRE) has described the 47,500 figure set in Cornwall as an "invasion of the countryside".
Penny Mills, chairman of Devon CPRE, said the county was already absorbing 6,000 new homes at Cranbrook, near Exeter, and another 5,000 at Sherford, east of Plymouth. In all, she said, at least 30,000 houses had either been permitted or were in the planning system.
"The requirement in Devon is not for huge new cities, however green and pleasant their new suburbs," she said. "It is for housing where there is a genuine requirement – small additions to villages, larger additions to the local towns where appropriate and developing brownfield sites first, and a massive investment in infrastructure, so that the South West has links to the rest of the country that can then make any new large-scale housing projects viable.
"Above all there remains a critical requirement for affordable housing. We have seen the gradual collapse of many small rural communities, now without pub, school, shop or other amenity, unreached by local bus, no railway nearby and increasingly isolated.
"The Government has major drive for sustainable development and will see this as a way of building large numbers of houses quickly
"For Devon this urban sprawl is the reverse of what is actually required if we are to house and provide work for those who live in this beautiful part of the country."
However, Exeter's Labour MP Ben Bradshaw said Mr Rudlin's concept "merits consideration".
He added: "Exeter is already expanding and it would be much better if we were doing so in a greener, better planned way.
"My concern is the current Government's approach is leading to haphazard urban sprawl. With housing costs now beyond the reach of many people we desperately need more homes that are affordable. This could be a way of providing them in an attractive, sustainable way."
Lord Wolfson, who funded the prize, said garden city schemes could reduce opposition which had contributed to the falling number of homes being built every year.
In the last 10 years, house building targets have been missed by 954,000 homes.
"Garden cities are far more popular than people think," Lord Wolfson, the chief executive of Next, said. "74% of people like the idea of garden cities. Only 13% of people in this country are against the building of garden cities.
"But we live in a funny country and people will protest very, very loudly but very quietly agree. That 13% is extremely vocal but they are a minority. If politicians can attack this issue with integrity they will find the majority of people are on their side."
