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Transport VKT
Age of vehicles travelling (vehicle kilometres travelled by vehicle age)
Older vehicles tend to have higher exhaust emissions of harmful pollutants, such as carbon monoxide, hydrocarbons and the oxides of nitrogen. This is partly due to deterioration in the engine’s efficiency, but also due to the older technology used in earlier engine designs.
Older vehicles may also have poorer fuel efficiency, and therefore create more greenhouse gases for each kilometre travelled than similar newer vehicles.
Age alone cannot be relied on to determine the environmental effects of road transport. Good vehicle maintenance can reduce harmful exhaust emissions.
Current situation
In 2007, the highest proportion of kilometres travelled in New Zealand (33 per cent) was completed by vehicles between eight and 12 years old. Thirty-two per cent of the New Zealand vehicle fleet falls into this age bracket, primarily because of the large number of used imported passenger vehicles of this age. The second largest group, contributing 23 per cent to total vehicle kilometres travelled (VKT), was 13 to 17 years old.
Total VKT by vehicle age in New Zealand, 2007
Data source: Ministry of Transport.
View data (including text description) for above graph
The contribution of used imported vehicles to total kilometres travelled in 2007 is biased towards older vehicles. New Zealand-new vehicles are responsible for most VKT in the younger age brackets. The import of older used vehicles into New Zealand has contributed to a slight increase in the average age of vehicles travelling on our roads.
Trend
In 2007, the average age of the vehicle fleet was 12.04 years, an increase from an average of 11.87 years in 2001. While this appears to be a relatively small change, when one considers the distance travelled compared to the age of the vehicle (also known as travel-weighted average age), the changing age profile of the New Zealand vehicle fleet becomes much clearer.
Since newer vehicles travel further on average than older vehicles, the travel-weighted average age is generally younger than the average age of the fleet. The travel-weighted average age of the light fleet increased from 10.7 years in 2001 to 11.3 years in 2007.
The gradual ageing of the New Zealand vehicle fleet is a trend shared by some other countries such as the United States. In New Zealand, this is caused in part by the increasing age of used imported vehicles. It also suggests that New Zealanders may be keeping their vehicles road-worthy for longer.
What can you do?
- Buying a new car or late-model car? Compare the environmental and fuel performance at www.rightcar.govt.nz and look for the vehicle's fuel economy label. The more stars, the more you will save on fuel and the lower your emissions.
- Taking public transport and sharing car trips can save you money on fuel and reduce your carbon dioxide emissions.
- Walking and cycling are ideally suited to short trips. It is good exercise and can save you money.
International comparison
The New Zealand vehicle fleet is relatively old by international standards. Our vehicles are, on average, nearly two years older than Australian vehicles and an even wider margin exists compared to other countries.
Average age of the New Zealand light fleet compared with other countries with similar per capita travel
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Notes:
(1) Data was not available for Canada in 2002 and the US in 2005 (2006 data for the US has been included instead).
(2) Median values have been used for the United States. Averages would be higher, if they had been available.
Data source: Ministry of Transport.
This information has come from the environmental report card on vehicle kilometres travelled by road.
Move to next variable reported on for VKT: Type of fuel used.
Last updated: March 2009
