• De-clutter your car for extra green points
  • Switch up your driving style and save on fuel
  • Check tyres and do your bit for the environment
An all-electric vehicle (or EV) emits nothing from the tailpipes (in fact, it doesn't even have them), while the CO2 emissions from the latest Prius hybrids level out at an estimated 70g/km[2].
But although some are predicting that the falling cost of batteries will make electric cars cheaper than their fossil-fuel equivalents by 2022, owning a green machine now is not always cost effective or practical for many drivers[3].
That doesn't mean that you can't contribute towards a cleaner, greener future, though. If we all made a few minor changes to our everyday driving habits, we could make a huge collective difference to the air we breathe – and save ourselves some cash in the process.

Easy tiger

Enjoying a favoured B-road when the sun is shining and traffic is clear remains one of life's great pleasures, but it does little for a vehicle's fuel consumption figures. 
ECOWILL, a project supported by Sustainable Energy Europe, suggests that anticipating the flow of traffic ahead and avoiding harsh braking are two very simple ways to eke out every last drop of fuel and reduce emissions, while cruising at 80mph can use up to 25 per cent more fuel than at 70mph[4].
Try shifting up a gear earlier, too. Moving from third directly to fifth gear when safely joining traffic on a motorway slip road, for example, will help keep the engine revolutions per minute (RPM) low and therefore use less fuel.
Green rating:
4 out of 5

Pump up the volume

As well as cranking the stereo up to '11' on a journey, why not try pumping up the pressure of your tyres too? A study by Michelin in 2015 discovered that UK motorists are wasting £246 million a year on fuel by driving with underinflated tyres[5]. 
'Underinflated tyres are dangerous, they use more fuel, they wear out quicker and they cause the car to produce more pollutants and greenhouse gases,' explains Jamie McWhir, car, van and 4x4 technical manager for Michelin in the UK.
The good news is that it's really easy to rectify, as all manufacturers will supply the correct tyre pressures for a vehicle. They're either located on the car (try the fuel filler cap or inside the door) or in the owner's manual. Next time you stop to fill up, pay the air pump a visit, too.
Green rating:
3 out of 5

Read the manual – get the mode

If you discovered your tyre pressure in the owner's manual, don't stop there!
Modern cars often come with functionality that allows drivers to change their drive style at the push of a button.
Volvo's 'Drive mode ECO', for example, reduces the power of the air conditioning and lowers ground clearance to reduce wind resistance[6]. Nissan's Eco-mode Function slows acceleration, except in emergency situations, while Renault boasts that its ECO mode can boost fuel economy by 10 per cent.
Green rating:
4 out of 5

Roll with it

The Energy Saving Trust advises that you should anticipate hills and take your foot off the gas when travelling downhill, or when approaching traffic lights and roundabouts[7].  
In many modern cars, this stops fuel from being sent to the engine, thus saving cash and reducing emissions. By remaining in gear, the driver still has full control of the vehicle. The more you can prevent a car from stopping and starting, the less fuel is required. 
Green rating:
3 out of 5

Stay slippery

Modern cars are designed to be as aerodynamic as possible, which means that adding anything to the roof is going to cause excess drag, slow the car down and make the engine work harder.
'It's amazing how many drivers you see hammering along the motorway with roof-racks or bulky roof boxes full of unnecessary stuff,' observes Nick Francis, motoring editor at The Sun on Sunday (@Nick_TheSun). 'If you don't need it, bin it,' he adds. 
If roof bars aren't required, take them off and leave them in the garage, while a quick de-clutter of the boot to reduce the load will also help. Lighten up – the planet will thank you for it.
Green rating:
3 out of 5

Healthy car, healthy planet

A well-maintained car will always outperform a neglected wreck in any eco challenge, so it's important to ensure that your engine is topped up with oil and your tyres are checked regularly, and that you stick to service intervals.
'Ensuring the correct engine oil levels is important, as it means an engine's internal parts remain lubricated and friction-free,' explains Lucy Moore, a car care expert at Halfords
'Regular servicing can also make a big difference, as an engine performs as its manufacturer intended when checked and maintained by a professional. That also means fewer pollutants in the air and a more economical vehicle,' she adds.
Green rating:
5 out of 5
If you're attached to your petrol or diesel car but still want to do more to save the planet, simple steps such as reducing weight, changing your driving habits and maintaining your engine can help – so you won't have to stump up for an electric or hybrid car.
Follow Leon Poultney on Twitter @Blokesincars for more great driving ideas.