BY Bill Garrett
BBC Money Programme
Many celebrities like 4x4s - especially hybrid ones
Whether you see them as gas guzzling monsters of the road or as versatile necessities of modern life, four-wheel drives have become the most controversial cars on the road, pitting environmental campaigners against car lovers and motor manufacturers.
Now the industry is fighting back by using new technology it says will improve the green credentials of their 4x4s.
Cars have always attracted their share of criticism from green campaigners, but expensive four- wheel drives, with their heavy fuel consumption and high carbon dioxide emissions, have become a particular target for activists in recent months. Now a group called The Alliance Against Urban 4x4s has started a campaign against their use in Britain's cities.
On a cold early morning in January this year, members of the group took to the streets of North London to leaflet parents dropping off their children on the school run.
Mums and dads driving their off-road vehicles through the narrow streets were presented with mock school reports giving bad marks for using vehicles the protestors claim are bad for the environment.
Sian Berry, one of the founders of the group, defends the tactics of the protestors. "We have been trying to point out to parents who are taking their children to school in 4x4s that they're polluting the air and they are basically making a very irresponsible choice".
Ups and downs
But the rise of the anti-4x4 protest groups spells bad news for the car industry.
These off-roaders - known as SUVs or Sport Utility Vehicles in the States - are amongst the few growth areas for the hard-pressed motor industry, and now virtually all manufacturers, from Ford to Honda, Porsche to Land Rover, include them in their model ranges.
Demand for SUVs has doubled in the UK in the last 10 years with 80,000 sold in 2004 alone, and that accounts for over 6% of all new cars sold here.
David Motton, editor of What Car?, argues that they appeal to people's desire to make their lives feel more exciting.
How the hybrids work
A hybrid car is powered by an electric motor
The motor's battery is recharged by an electric generator which is powered by a petrol engine
Since the petrol engine runs at an optimal speed, it consumes fuel in a more efficient way than traditional petrol engines
Additional power to the battery comes from kinetic energy from the wheels when the car is slowing down
The petrol engine provides extra power for the car when required
"Maybe you are just on the way to the supermarket, but you might feel that if the mood takes you, you could dash off to Snowdonia.
"It just gives you a sense that perhaps life might be a bit more adventurous than the humdrum life that most of us really lead."
So the big problem for the car industry is how to hold on to this profitable and glamorous sector of the market whilst appeasing the environmentalists.
Escape to victory
Ford think they might have the answer by incorporating what is known as hybrid engine technology into some of their SUVs.
Hybrid vehicles are powered by a combination of a petrol engine and an electric motor, and the effect of this dual power source is to reduce both fuel consumption and carbon emissions.
They have now launched the new Ford Escape Hybrid in the USA, the world's first commercially-available hybrid SUV.
Mary Ann Wright, head engineer for hybrid technology at Ford, believes the company is responding to the concerns of its customers.
"We love our big bodacious SUVs, but in recent years we are not feeling quite so good about driving them because of the environmental footprint that they leave. And we are looking to create a product that would appeal to the environmentally-conscious consumer and the [Ford] Escape was perfect".
But is this a genuine effort to improve the green credentials of the SUV, or simply an attempt to make it more marketable?
Last year, Lexus, the luxury offshoot of Toyota, unveiled the Lexus RX 400h hybrid off-roader at European motor shows. It will be the first hybrid 4x4 to reach the UK market later this spring.
At a cost of over £40,000 it will be considerably more expensive than its petrol-only counterpart, but Lexus is hoping that customers will be won over both by the idea of lower fuel consumption and the concept of guilt-free 4x4 motoring.
John Wormald, co-author of "Time for a Model Change", an analysis of the worldwide motor industry, argues that the industry is trying hard to balance the needs of its customers against growing environmental concerns.
"It's a classic contradiction... between the interests of the individual and the interests of society or of the global community. SUV hybrids are a way of reconciling those two conflicting interests, a way of being able to keep a larger vehicle without its being quite so thirsty and polluting."
Whatever the environmental arguments, the 4x4 is undoubtedly here to stay - the motor industry has invested too much to let it become a passing fad.
Whether the anti-4x4 campaigners can ever be persuaded that greener SUVs represent a genuine concession to environmental concerns is more of an open question.
The gas-guzzlers versus the greens will be broadcast on BBC Two on Friday 1 April at 1900.