The following chart shows the emissions associated with the various forms of transport.
Source: "How to reduce greenhouse gas emissions, save money and maintain quality of life" - Rose 2006
Take Public Transport
Catching public transport is a great way of reducing your emissions. It is amazing that so many people spend so much of their time on the freeway carparks when they could be relaxing in a chauffeur driven bus or train. Surely most of these people have no idea how much it costs them to commute to work every day. The average Perth commuter would save $7000 a year by selling their second car and taking public transport instead. This is equivalent to a pay rise of up to $12,500!!
Car Pool or Downsize Your Car
You can also reduce your transportation emissions by car pooling, downsizing your car (when it comes time to replace your car) or choose a fuel efficient vehicle such as a Toyota Prius Hybrid or Honda Civic Hybrid. The following information is current as at May 2008 and comes from the Federal Government's Green Vehicle Guide.
Buy Second Hand
If you are looking at a new car, try buying second hand rather than new. There are significant embodied emissions involved in the production of motor vehicles. It can take many years to "pay off" the emissions from the purchase of a new vehicle. However make sure you buy a second hand car that scores well in the green vehicle guide - http://www.greenvehicleguide.gov.au
Reduce Fuel Consumption By Driving Better
Your driving style also can have a big impact on the fuel economy of your car. Avoid accelerating rapidly, don't follow too closely behind the vehicle in front so that you can maintain a more constant speed. If you are stationary at the traffic lights or stuck in a traffic jam try turning off the engine.
Don't Carry Excess Weight in Your Car
Make sure you aren't carrying excess weight in the car. Remove roof racks when not in use.
Diesel is NOT Better than Petrol
Interestingly, there is generally less than 5 % difference between petrol and diesel cars in their greenhouse gas emissions. Although diesels emit slightly less GHG, they are generally worse for particulate emissions (smoke), which can have other negative health effects. Diesel is a higher energy fuel than petrol so less is used, but this is negated by its higher emission factor, making it similar to petrol for GHG emissions per km.
LPG is a Good Option & It's Save You Money
LPG vehicles emit about 14% less GHG emissions than petrol vehicles – a significant improvement. LPG has lower energy content than petrol, so more is used per km, but it has a much lower emission factor.
The only really effective way to reduce your vehicle emissions is to select the lightest, most fuel efficient model that you would use to full capacity most of the time.
Keep Your Car For Longer
In addition to the energy and GHG emissions from the fuel used by your cars, there are embodied energy emissions from their manufacture. For vehicles traveling average distances over their lifetime, embodied emissions usually amount to about ¼ of the fuel emissions. Annual embodied emissions = emissions from materials processing, manufacture and maintenance divided by the life of the vehicle. Even if a vehicle is not being used it still incurs embodied emissions.
Making a vehicle last longer can reduce embodied emissions. However there will only be a reduction in total emissions if its fuel efficiency is at least equal to the new model. Keeping an old vehicle that is inefficient and polluting will cause much more GHG emissions from the extra fuel burned than are saved in embodied emissions.
Thinking About Buying a Four Wheel Drive?
If at all possible - DON'T!!
If you need a heavy vehicle or 4WD only occasionally consider just hiring one when required. By purchasing a smaller standard (non-4WD) vehicle for general day-to-day commuting you will save many thousands of dollar on the purchase price of the vehicle and, depending on the vehicle you choose, will save thousands of dollars per year in fuel and maintenance costs.