Wednesday's Budget piled the pressure on motorists to become greener, with higher duty to pay on the most polluting new cars. As the story opposite explains, the measures mean greener drivers will pay much lower road tax charges.
Although almost no-one will escape the duty altogether - despite the Chancellor's claims in his Budget speech on Wednesday - the new rates of duty do give drivers genuine financial incentives to move to greener cars. Nor was the Budget announcement an isolated measure, with ministers increasingly keen to persuade drivers to act more responsibly.
On Monday, the Department of Transport announced that a new one-mile car-share lane will open next year at a West Yorkshire junction. It will allow cars carrying more than one person priority entry from the M606 southbound on to the eastbound M62, apparently cutting rush-hour journeys by an average of eight minutes.
As a happy by-product, car sharing lanes should ensure there are fewer cars on the road overall, and reduce the costs of motorists who share.
Rising fuel prices have already encouraged many drivers to become more environmentally-friendly, with a third (11.5 million) of British motorists cutting back on road journeys over the last 12 months.
Some use their cars only for essential journeys while others have increased their use of public transport, research by the insurer More Than suggests. In fact there are all sorts of ways you can cut your motoring costs while being greener.
You could save up to ??1,000 on transport costs every year by car or liftsharing, according to the organisation Liftshare.
Very simply, this involves two or more people sharing a car and travelling together. Typically the party will consist of the vehicle's owner with others usually contributing towards the cost of fuel.
Using up what would ordinarily be free seats in cars can prove a simple way of cutting the cost of driving and reducing congestion and pollution.
Liftsharing can happen informally, where friends, family or neighbours take turns to give each other lifts, or more formally through the increasing number of council run schemes or through online services such as www.liftshare.co.uk .
On this site, users register regular or one-off journeys they are about to take and are put in contact with other travellers who are going their way.
Drivers are not permitted to make a profit from providing a lift, but a contribution from passengers can include an appropriate amount towards wear and tear. "Fares" must be decided in advance, and the driver is not permitted to act as a taxi, picking up strangers along the route.
If you drive less than 6,000 miles in a year, joining a car club could save you between ??1,000 and ??1,500 a year, according to the organisation Carplus. Car clubs are typically run by local councils or private businesses and allow the short-term hire of cars, freeing members up from car maintenance and tax costs.
This "pay-as-you-go" approach to driving also reduces the amount of unnecessary car journeys, helping to combat pollution and congestion.
Drivers can expect to pay a joining fee of up to ??40, a deposit of around ??100, hourly charges of up to around ??4.50. In addition, there's a fuel charge per mile of up to around 18p. Typically, once you are a member of a club, you simply book the time you need, enter a pin to access the car and then drive off.
At www.carplus.org.uk you can track down car clubs in your area or check out the guidance it offers on starting your own informal car club.
City Car Club (08453 301 234 www.citycarclub.co.uk ) has cars stationed in reserved parking bays in locations nationwide including Edinburgh, London, Bath, Bristol, Brighton & Hove, Litchfield, Huddersfield, Poole and Portsmouth.
While electric cars can sometimes cost ??5,500 more than conventional vehicles, according to the Energy Saving Trust ( www.est.org.uk 020 7222 0101), they can cost as little as 1p a mile to run.
In addition, electric cars are not subject to road tax and, as an added bonus for London drivers, enjoy 100 per cent congestion charge discount. Drivers living in areas where residential parking demands paying for a permit might also find that they get a discount on this cost.
Electric cars use a battery and electric motor to power the vehicle meaning they have no emissions at the point of use.
Due to the capacity of the battery, their range is limited to about 60 miles or less between recharges, making them best suited for city-based users.
Electric vehicles can be recharged by plugging them into an existing electrical socket and some city councils are installing electric recharging points in car parks or on-street.
The G-Wiz model ( www.goingreen.co.uk ) claims to consume just one quarter of the energy of a similar sized petrol car. The makers say it costs around ??1.64 a day to run, equivalent to around 600 miles per gallon. The list price is ??8,299, but it is currently on offer at ??7,799 and orders for cars placed by 31 March come with free leather seats worth ??499.
Hybrid vehicles, such as the Toyota Prius, Honda Insight and Honda Civic IMA, run on a combination of a petrol engine and an electric motor powered by an energy storage device such as a battery pack.
All hybrids use regenerative braking, which means that energy is put back into the battery when braking. This improves energy efficiency and also reduces brake wear.
Hybrid technologies improve fuel efficiency and therefore provide considerable fuel savings compared with a normal petrol vehicle. While models might cost between ??1,000-??3,000 more than conventional cars, running costs are two thirds that of equivalent petrol fuelled vehicles, according to the Energy Saving Trust.
Hybrids also benefit from reduced vehicle excise duty and do even better after the Budget. In addition they are exempted from the London congestion charge.
CHOOSE LESS POLLUTING STANDARD CARDS
The Vehicle Certification Agency guide ( www.vcacarfueldata.org.uk ) provides information on the fuel economy and emissions performance of all new cars on the market in the UK.
The guide indicates there can be significant differences (up to 45 per cent) in the fuel economy of different models using the same fuel within the same size range and that by choosing the most fuel-efficient vehicles you could save ??900 per year assuming your vehicle is doing 20,000 miles a year.
Using Government data, Friends of the Earth ( www.foe.co.uk ) calculated the cost of fuel needed to drive a car 12,000 miles a year and found that for drivers wanting a smaller car, buying a Citroen C2 rather than a Ford Fiesta could result in a fuel cost saving of up to ??460 a year.
Alternatively, drivers looking for a family car could go for a Toyota Prius, rather than a Ford Mondeo and pick up fuel cost savings of about ??630 a year. Even those unpopular 4x4 drivers have a choice, because by opting for a Toyota RAV 4 instead of a Land Rover Discovery generates fuel cost savings of around ??1,500 a year, or ??120 a month, suggest the Friends of the Earth findings.
Also bear in mind that the company car tax system is skewed to reward drivers of fuel efficient vehicles.
CHANGE THE WAY YOU USE YOUR CAR
You could begin to save money and help cut your carbon emissions by getting into some good fuel-saving ways suggested by the Vehicle Certification Agency.
These ideas include avoiding using your car for short journeys and using public transport, bicycles or taking a walk as often as you can. Also, get into the habit of driving off as soon as possible after starting your engine rather than leave it ticking over. Driving smoothly helps too, as harsh acceleration and heavy braking have a significant effect on fuel consumption and driving more smoothly saves fuel.
Driving at high speeds significantly increases fuel consumption so think about slowing down. Observing speed limits on motorways, for example, will save fuel.
Also, avoiding carrying unnecessary weight by removing roof racks when you don't need them and ensuring tyres are inflated to the correct pressure for the vehicle will cut the amount of fuel you use, as will only using the air-conditioning sparingly.
Budget promises zero tax for eco-friendly drivers
The much-trailed suggestion that the Chancellor would hit drivers of 4x4 " utility" vehicles (the so-called "Chelsea tractors") came true this week. Mr Brown has targeted vehicles that belch out more than 225g of carbon dioxide per kilometre with a new higher rate of Vehicle Excise Duty (VED) of ??210 a year.
Meanwhile, VED on the lowest-emission vehicles is now zero. But since electric cars are already exempt, no new cars will actually qualify for the zero rating, as the carbon emissions required (less than 100g per kilometre) has been set so low.
The best-known ecofriendly car, the Toyota Prius (right), has emissions of 104g a kilometre, which puts it into the second-lowest VED band, with a duty of ??40. It is joined by petrol-driven cars such as the Peugeot 107, the Toyota Aygo, the Smart city coup?©, Daihatsu's Charade and Sirion and the Vauxhall Corsa.
Some small-engine diesel models also qualify for the ??40 band. They include the Citro?«n C2 and C3, the Renault Clio, the Peugeot 206, the Fiat Panda, the Ford Fiesta, the Vauxhall Corsa, the Peugeot 1007 and the Smart forfour.
At the other end of the scale, VED goes up in bands as emissions increase. The top rate will hit cars such as the Range Rover.
'I saved a load of money sharing'
"I found a way to save money immediately, as well as benefit the environment, with no outlay at all," says Rhydian Lewis, a 30-year-old network engineer and enthusiastic lift-sharer from Chepstow.
Not long after registering on Liftshare.co.uk he received an e-mail requesting a lift-share. "As it turned out, the chap who had got in touch sat about 30 metres away from me in the office and lived up the road from me in Cwmbran," Rhydian explains.
"We started to share the drive, and then a couple of other guys from Wales noticed us sharing and joined in. That saved me a load of money."
Recently, Rydian went freelance and often works from home, but he estimates a total of five years lift-sharing saved him around ??4,500, both through reduced fuel costs and toll savings on the Severn Bridge.
"The environmental benefit has been massive, too," he adds. " That may not have been my immediate priority but it's a great side effect."