Car wars: The green 4x4 is the car of the future. But it's no match for the Chelsea tractor. Why?

Because Gordon won't hit the gas-guzzlers where it hurts. Because drivers think big is beautiful. And because even the green fuels minister trashes Prius drivers as 'salad eaters'. Severin Carrell asks why environmentally friendly cars are gridlocked on the drawing board

The car of the future is here already. The technology exists to build an affordable, mass-market green car that runs on cleaner, more efficient fuel and does not help to destroy the environment like its gas-guzzling rivals. We want to drive it, or so the opinion polls say. There is no scientific reason why it should not be selling in the same numbers as, say, the Ford Focus. So where is this green dream machine?

Not on the forecourts. It is stalled in development, the power of its progress drained by a motor industry that does not really want it, a drivers' lobby that sees driving a 4x4 or "Chelsea tractor" as a civil right, and a government that is making small gestures while the planet suffers.

Environmentalists lament the Chancellor's Budget decision last week to make 4x4 drivers pay just £45 a year more for driving their £60,000 vehicles. But now The Independent on Sunday can reveal that an ambitious £16m scheme to give buyers up to £1,000 to buy green cars has been blocked by a senior minister, who dismisses environmentally friendly drivers as "salad eaters".

Stephen Ladyman, the transport minister responsible for green fuels, drives a new diesel-powered Alfa Romeo GT. He has a passion for sports cars and motorbikes. And he is being blamed for personally resisting plans to subsidise the purchase of cars with low carbon dioxide emissions such as the Citroën C1 and Toyota Aygo.

The "low-carbon car" scheme would also give grants for converting existing cars to green fuels, and running buses on hydrogen. But it has been held up for 14 months now. Mr Ladyman and his officials say it would be clumsy and inefficient to promote green driving by helping to fund the sale of about 7,000 cars a year while more than 2.5 million others are also sold. A spokeswoman for the Department of Transport said the scheme was actually being delayed by the European Commission, which is questioning whether it breaches rules on state subsidies. But green campaigners - pausing from chewing their salad for a moment - blame the minister, whom they call "a petrolhead".

If so, he may not be as out of step with public opinion as they would like to think. Britain has fallen in love with big, fuel-thirsty cars. While new vehicles are generally becoming more fuel efficient, British motorists are buying increasing numbers of larger SUVs like the Land Rover Discovery - undermining attempts to tackle climate change and increasing the UK's carbon dioxide levels. Whatever we tell the pollsters about our eco-intentions, the facts are that sales of 4x4s jumped from 159,000 in 2003 to 187,000 last year, while sales of cleaner "mini-cars" fell from 39,000 to 27,000. CO ₂ emissions from all private cars went up.

Britain has signed up with the rest of Europe to hit a target of 140g per kilometre for the average new car's carbon emissions by 2008, but at the current rate of decline looks unlikely to make it until 2022. "Europe is doing badly," says Richard Tarboton of the Energy Savings Trust, the Government's official agency for energy efficiency, "but Britain is doing really badly."

Even Americans are getting the message: sales of the highly efficient Toyota petrol/battery hybrid, the Prius, rocketed to 100,000 in the US last year thanks to the endorsement of stars such as Brad Pitt. But here, where celebrities are more likely to drive Land Rovers and green motoring is seen as quaint, Toyota sold just 3,746 Priuses. It needs a celebrity champion if it is going to break through, but that is unlikely to be Quentin Willson. The television presenter and motoring journalist has recently bought a Range Rover that does just 18.7 miles to the gallon. "It is," he admits with devilish glee, "Satan's own vehicle."

Programmes such as Top Gear, which Willson used to present, promote the idea that driving is a macho business, big is beautiful when it comes to engines, and the best vehicles in the world are high-performance sports cars that do about a foot to the gallon. Or tanks. They're really tough. And safe - one reason why affluent mothers would rather negotiate the suburban school run in an off-road monster. But rather than question the motives of 4x4 drivers like himself, Willson says it is the Chancellor who should be taking the bull-bars by the horns. The new top rate of road tax, £215, is derisory, he says. "It is craven. He is the Prime Minister in waiting and he does not want to take on the SUV-driving middle classes. There is so much more he could do: in Ireland it costs £1,000 to tax a 4x4. That is the level of tax that would change people's behaviour."

Mr Brown did also cut duty for the greenest cars to zero. But if the Government's green transport advisers, the EST and the Low Carbon Vehicle Partnership, get their way the tax regime will become far more punitive in future. As The Independent on Sunday reported last year, they want a top rate as high as £900, while the greenest cars could even be made available at government-funded discounts.

Even that might not make people want to buy them. The advisers believe there are three main reasons why there is not more of a market for green cars: the low level of financial incentives; the way the industry markets and sells its luxury vehicles; and public ignorance and apathy about the links between climate and motoring. Greg Archer, chief executive of the LowCVP, a government-funded collaboration between car-makers, fuel companies and greens, has discovered a range of remarkable myths that people believe about new technologies.

Many motorists believe the Toyota Prius needs to be plugged into the mains each night to recharge its battery. It does not. Few drivers understand the link between climate change and fuel economy. "Most drivers still talk about carbon monoxide and lead in petrol as being the main environment problems from cars. Most people still think LPG is dangerous," he said. It is not.

Richard Tarboton at the EST believes a campaign is needed to educate motorists on fuel use and climate change with a simple "league table" which ranks every car by its CO ₂ emissions.

Car salesmen also need re-educating. One major reason for the massive push to sell 4x4s is that they earn car-makers and salesmen much greater profits than mass-market cars such as the Ford Focus or Vauxhall Astra, among which competition is much tougher. "You can't expect car makers to stop producing profitable models," said Mr Tarboton. "We need to change the market, so it's really profitable to produce mass-market cars."

One answer would be to introduce "carbon trading" for all car-makers, where every new car would have a CO ₂ voucher. If a car was fuel efficient, that voucher would earn the car-maker a carbon credit, but if it was a gas-guzzler, it would cost the car-maker a carbon credit. This would force luxury car-makers to cut fuel consumption and to buy carbon credits from fuel-efficient car makers. This idea, while complicated to set up, is getting serious attention in the car industry and the Government.

The manufacturers know they have to do something. Political pressure is growing and activists are becoming bolder. Last year a dozen members of Greenpeace infiltrated the Land Rover assembly line and chained themselves to new Freelanders, the most popular 4x4 of all.

While Land Rover has been quick to exploit the new taste for big cars it has been slower - in common with other SUV makers - to display new "energy labels" on the forecourt to show how fuel efficient new cars are. Now, with Mr Brown's new tax band, a deep red label tells buyers that the Discovery and Range Rover are among the most polluting of all. However, Land Rover is throwing its engineering muscle and the might of its parent company, Ford, into going green.

At the Geneva motor show earlier this month, it unveiled the LAND_e concept vehicle - an odd-looking skeletal demonstration model which showed off some dramatic new technologies which could cut a Land Rover's fuel consumption by 30 per cent.

The LAND_e boasts a hybrid diesel engine that uses batteries at low speeds, recharging itself when the car is braked; it uses "stop start" technology which cuts the engine off at traffic lights; recycles exhaust fumes to heat the engine up quicker; and, lastly, uses climate-friendly bio-diesel fuel made partly from crops.

Yet there are no plans to build the LAND_e itself. Instead, these innovations will be introduced into nearly all its models in 2008 or 2009. Some, such as the most expensive Freelanders, Discoveries and Range Rovers, will benefit most. All their diesel engines, for instance, will be able to run on bio-diesel.

But it will take at least two years before the first "green" Land Rover - the smallest of its models, the Freelander - rolls off the assembly line. Today, there is only one 4x4 on the market that can claim to be moderately green, the Lexus RS400h, which uses a hybrid petrol/battery-powered engine. Yet it comes in at only 35 miles per gallon - a figure no better than the conventionally powered Freelander.

If more radical solutions are to be found, and a popular green car finally to be brought to market, then Mr Brown and his biker friend Mr Ladyman will need to do far more to promote green fuels by dramatically cutting the cost of climate-friendly bio-fuels made from renewal crops like sugar beet or oilseed rape.

The Swedish car-maker Saab unveiled its climate-friendly 9-5 BioPower saloon earlier this year. It can run on pure plant-based bioethanol. As yet there are 10 places in the UK where this fuel can be bought, all in rural areas. The fuel is only slightly cheaper than unleaded and uses up to 30 per cent more bioethanol than unleaded petrol.

But there is one sobering fact for the green lobby to absorb. The Chancellor's new strategy may be shrewder than many people realise. Because of the failure of car-makers to build truly green mass-market cars, as yet there are no cars on sale that qualify for the zero-rated vehicle excise duty. None.

There is a big gap in the market. The technology exists to fill it. Now somebody just has to find the will.

Motor Mouths: You are what you drive

Wayne Hemingway DRIVES A TOYOTA PRIUS

I think 4x4 drivers must be totally deaf and dumb. You would have to be pretty thick-skinned to be impervious to all the criticism of these gas-guzzlers. Some people just want to be difficult

Jodie Marsh DRIVES AN AUDI TT

I love monster pick-up trucks, but I like all sorts of cars and the one I have now is the best car I've had. It's quick, girly and cute. I love cars but I'm not one of these people that thinks a Ferrari or a Lamborghini is the be-all and end-all

Quentin Willson DRIVES A RANGE ROVER

Every time I go to a petrol pump I worry desperately. I'd love to drive something more efficient. I am very anxious that somebody needs to do something about the cars we drive - and fast

Jeremy Clarkson DRIVES A FORD GT COUPÉ

You may think the reason people spit at 4x4s these days has something to do with Greenland's blanket of ice. It isn't. It's because you're well off

Jodie Kidd DRIVES A MASERATI

I'm a real car enthusiast. Driving is fantastic. It's a lot of fun. I absolutely love it. Cars are just like horses. I learnt as a kid how to keep a horse balanced, so in the car I can corner and steer subconsciously