What are the facts on cars and the environment?

Carbon Dioxide (CO_²) Emissions:

Although the car is getting better in terms of fuel efficiency, consumption and emissions, there is still a long way to go. The main concern is that of CO_² emissions. Currently Toyota lead the market for low emission cars. On average a standard five door hatchback will produce 162 g/km of CO_², with the new cars such as the Prius some models have got this down to 80 g/km (e.g the Honda Insight - no longer made). Nobody is denying the obvious advantages to driving cars, however in an age where we have mass transport and integrated public service systems the need for individual personal transport should be decreasing.

Carbon Dioxide produced in the building and disposal:

Another factor is the damage caused by manufacture, operation and disposal of each vehicle. This is estimated at around 20-25% of the damage caused by burning the fuel in each vehicle. Note that electric cars are sometimes said to be zero CO_² polluters, but this ignores the manufacturing and disposal and other operating factors, and the CO_² produced in electricity generating stations. Other operating factors include fuel refining distribution for cars using petrol or diesel. Cars driven by solar panels may get closer to zero CO_², but the manufacturing of the panels is an additional concern.

CO_² emission/energy/and other pollutants Although CO_² is thought to be the major contributor to greenhouse gases emitted by vehicles, there is additionally concern about energy efficiency and other pollutants. There is a loose, but not exact, correlation between CO_² emission and energy/fuel efficiency. Regarding other pollutants which damage the environment, most cars produced and used in developed countries are now satisfactory regarding particulate emission, and the emission of other pollutants, such as lead compounds. This is not true globally however, and there can be serious environmental contamination due to these pollutants in some developing countries.

Role of the US:

The US is the world leader for numbers of cars in a country and unfortunately all of the CO_² being expelled by those cars is contributing to the global warming effects we are all noticing. Currently it is believed that reversing what we have done is impossible, but operations like carbon sequestration (look up at wikipedia) could stand to help things.

Carbon offsetting Carbon offsetting is an arguably controversial means for permitting the use of fossil fuel burning machines. For example, by planting trees, or paying for forests to not be cut down, the global effect on CO_² emission can be minimised.

First answer by Redbeard. Last edit by Dave2010. Contributor trust: 47 [recommend contributor]. Question popularity: 55 [recommend question]