To drive or not to drive? That’s the question at the forefront of many minds as rising fuel costs, increasing carbon emissions and notions of destroying the planet one car at a time consume Brits with four-wheeled guilt.

While some of us have responded by swapping our gas-guzzling 4x4s for electric G-Wizzes, the rest of us are confined to a green-induced panic that has resulted in immobilised confusion.

According to a survey for the British International Motor Show, held earlier this month in London, 70 per cent of Brits want to lower their emissions while driving, but 60 per cent have no idea how to do so.

It’s not just about cutting CO2 – confusion over terminology means that one out of five Brits thinks biofuels are cars that run on two different kinds of fuel and four per cent believe that a hybrid is two cars welded into one.

But with the Government turning fuel efficiency – also dubbed ‘eco-driving’ – into part of the driving test from the end of the year, Brits can no longer get away with feigning ignorance.

After being taught how to accelerate and brake more smoothly, change gears sooner and drive at climate change-friendly levels, we’ll be expected to cut emissions, lower our fuel costs and help save the world – whether we want to or not.

“Motorists are ignorant but it’s not entirely their fault,” says Philip Sellwood, chief executive officer of Government agency the Energy Saving Trust, which has released a report, Driven, on the UK’s passenger car market.

“Three-quarters of people we surveyed don’t know what their own car’s emissions are, despite the industry launching a voluntary labelling system.

“And while 90 per cent of people want to drive greener, it’s really up to the dealers and manufacturers to make that happen.

“Salesmen at dealerships get bonuses related to the size of the cars they sell, so they have no incentive to sell one that has lower emissions.

“The trick for the consumer is to ask questions like, ‘What’s the greenest option here?’ By choosing the lowest-emitting vehicle you can save up to 15 per cent on your fuel efficiency – which could equate into Brits saving £6 billion a year in fuel costs.”

Where do I start?

If you’d like to swap your hunk o’ junk for an emerald gem, check out the Department for Transport’s ACT ON CO2 pages at dft.gov.uk.

You can choose what kind of car you want (such as an estate or MPV), the gearbox (manual or automatic) and the fuel type (petrol, diesel, or hybrid, and so on). The greenest choices are rated in descending order for you to choose accordingly.

The Environmental Transport Association also publishes a Green Car Buyers’ Guide, which not only helps you choose a greener car from their database but also lists the ten best and ten worst cars in terms of CO2 emissions and fuel costs. Check out eta.co.uk.

Once you’ve found something you might like, check out the car in the showroom. All new cars are required to have an environmental label that lists their CO2 emissions.

Like a new fridge, cars are best when they’re rated A and less worth your while as they descend the alphabet (G is the lowest). The Vehicle Certification Agency – vca.gov.uk – also lists cars’ fuel economy and CO2 data.

Can’t afford a new car? Don’t worry – you can still save the planet by buying secondhand.

The Society of Motor Manufacturers and Traders – smmt.co.uk – has a database of vehicle CO2 emissions going back to January 1997, and the VCA website lists cars’ emissions from 2000 in the downloads section.

And if you’re getting rid of your rusty wheels, Recycleyourcar.co.uk has advice on how you can recycle your old car in an environmentally friendly way.

What kind of car should I opt for?

Do you think a hybrid is two cars welded together? Fear not – green motorist Adam Vaughan, editor of ethical website SmartPlanet.com, explains the basics.

“Hybrids have two motors that work in tandem,” he explains. “There’s a conventional petrol engine and an electric engine, which extends the fuel efficiency of the car.

“The Toyota Prius and Honda Civic Hybrid are nearly identical, but they are a bit pricey – so for people on a budget, I’d recommend a diesel, like a Ford Focus.”

The EST’s Philip Sellwood agrees that diesel can be a green option due to its fuel efficiency. “If I were driving in the city, I’d go for a Vauxhall Corsa 1.3 diesel (starred 5/5 by the ETA),” he says. “And a Ford Mondeo 1.8 (also a 5/5 by the ETA) is a good, fuel-efficient family car.”

What about electric cars? “It’s a car powered by electric battery, which you charge from points all over the city or at home,” Adam explains. “You get cheap road tax, free parking and no congestion charge. G-Wiz and Mega City are good, reliable options.”

If you think they look a bit funny, and would rather opt for a car with a bit more bling, “the 520 BMW is a touring estate car, which will cost you £1,100 in fuel a year and is fantastic for where it sits in its class,” suggests Sellwood.

Otherwise, says Adam, “the Lexus Hybrid is a luxury car with greener options if you’ve got money to burn”.

If the credit crunch has hit you hard and you’d rather stick with the car you’ve got, see if you can’t lower your emissions and bills at the same time – just see our tips above.

Top five tips for efficient driving:

1. Drive like your granny: Accelerate and break slowly like your instructor taught you. It’ll save you gas and money.

2. Shift gears quickly. Shift up into second and fourth as fast as possible - you’ll save fuel that way. The EST advises changing up before 2,500rpm for petrol and 2,000rpm for diesel cars.

3. Consider your aerodynamics. Have you got roof racks or bike carriers that you leave even when not in use? Taking them off will increase your fuel efficiency, says the EST.

4. Join a car club. For a relatively small fee you have access to a city-wide network of good, well-maintained and eco-friendly cars. Or try a carpool.

5. Turn off the air-con and keep your car maintained: Using air-conditioning adds 5per cent to your emissions, so by turning it off and by keeping your tyres pumped up, you’ll be able to save yourself fuel and money.